Thread: [Jsbsim-devel] Helicopter

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Anyone here ever done one ?

Want to talk about it, share knowledge ?

Simon

Simon,

I had devoted some brain cells towards that idea a while ago, but never implemented it.

Imagine a point mass, with a point vertical force located above it. At 50% collective, vertical force equals weight. Cyclic tilts that vertical force fore/aft, left/right. Displacing the cyclic yields a slight loss (sine of angle) loss of lift, requiring slightly more collective.

The painful part comes when you try to fly it with a joystick. When you release the joystick, the cyclic returns back to neutral, the aircraft will slow to a hover. You basically need a joystick that has a trim lever, or allows you to reestablish the trim point.

Enough to get your brain cells excited?

Bill

From: Simon Julie Morley via Jsbsim-devel [mailto:jsb...@li...] 
Sent: Sunday, October 25, 2020 1:41 PM
To: Development issues <Jsb...@li...>
Cc: Simon Julie Morley <sim...@go...>
Subject: [Jsbsim-devel] Helicopter

Anyone here ever done one ?

Want to talk about it, share knowledge ?

Simon

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Hi Bill,

Thanks for taking.

I'm currently using a mouse with a saitek throttle and so haven't ran into
this issue.

I'll have to give it some thought to how to create a trim cyclic for
joystick users, if the workload is considered onerous over a long flight.

I chose to use a turbine and prop combination, which I'm really happy with.

I'm happy with the flight characteristics after adapting it to have a
stabilizing rotation around the lift point.

Regards

Simon.

On Sun, 25 Oct 2020, 18:08 Bill Galbraith, <bil...@gm...> wrote:

> Simon,
>
>
>
> I had devoted some brain cells towards that idea a while ago, but never
> implemented it.
>
>
>
> Imagine a point mass, with a point vertical force located above it. At 50%
> collective, vertical force equals weight. Cyclic tilts that vertical force
> fore/aft, left/right. Displacing the cyclic yields a slight loss (sine of
> angle) loss of lift, requiring slightly more collective.
>
>
>
> The painful part comes when you try to fly it with a joystick. When you
> release the joystick, the cyclic returns back to neutral, the aircraft will
> slow to a hover. You basically need a joystick that has a trim lever, or
> allows you to reestablish the trim point.
>
>
>
> Enough to get your brain cells excited?
>
>
>
> Bill
>
>
>
> *From:* Simon Julie Morley via Jsbsim-devel [mailto:
> jsb...@li...]
> *Sent:* Sunday, October 25, 2020 1:41 PM
> *To:* Development issues <Jsb...@li...>
> *Cc:* Simon Julie Morley <sim...@go...>
> *Subject:* [Jsbsim-devel] Helicopter
>
>
>
> Anyone here ever done one ?
>
>
>
> Want to talk about it, share knowledge ?
>
>
>
> Simon
>
>
>
>
>
>
> ------------------------------
>
> [image: Image removed by sender. AVG logo]
> <https://www.avg.com/internet-security>
>
> This email has been checked for viruses by AVG antivirus software.
> www.avg.com <https://www.avg.com/internet-security>
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>
>
> _______________________________________________
> Jsbsim-devel mailing list
> Jsb...@li...
> https://lists.sourceforge.net/lists/listinfo/jsbsim-devel
> _______________________________________________
> The JSBSim Flight Dynamics Model project
> http://www.JSBSim.org
> _______________________________________________
>
>

Simon, et.al. 

A little education, specially about the Sikorsky H60 line. Other helicopters are similar. Maybe some of this is known, maybe not.

The control system is fully irreversible. The cyclic and collective just over hydraulic valves which move actuators. The trim system provides a centering force when displaced from a set position through some centering springs. Without it, the cyclic and collective just move about willy-nilly (that’s a technical term). For our discussion, let’s assume that in a hover, the cyclic is centered, at 50% fore/aft throw, and at 100 knots, the cyclic has to move forward 10%, to about 40% throw (0% forward, 100% aft). So, Joe Pilot is in a hover. He will probably move the cyclic forward to 30-35% to get the aircraft accelerating forward (which drops the nose, and a bit of altitude can be lost). When Joe reaches 100 knots, he moved the stick a position where the aircraft neither accelerators or decelerates, about 40%. Now, when he establishes a new trim position, he can do this one of two ways: 

1.     Move the stick against the force springs, momentary press and release the trim release button. This establishes the new trim position where the stick is at when the trim release button is release. The force is instantly removed, and will remain where it is placed.

2.     Press the trim release button, and move the stick without the centering force. Once the desired position is reached, release the trim release button, and the new trim position is established when the button is release.

Now, let’s take this system onto the PC, with a conventional spring-centering joystick (centers at 50%). Hover, not a problem. Accelerate to 100 knots, you’ll have to hold a constant forward joystick. You might be able to implement a ‘trim position’ when you press a button on the joystick, and then move the joystick back to center within one second. When you pressed that button, it records the ‘trim’ position as 10%, and adds that to the stick position, maybe feeding it in over a second, or maybe it feeds it in as the stick is centered, regardless of how long it takes.

In your case, since you are using a mouse for a cyclic, that’s not really a problem.

I might suggest using a non-linear scaling on the stick, such as a squared-function. That makes the stick less touchy.

Good luck. Keep us informed how it is going. Hope everyone else enjoyed the read.

Bill

From: Simon Julie Morley via Jsbsim-devel [mailto:jsb...@li...] 
Sent: Sunday, October 25, 2020 2:37 PM
To: Development issues <Jsb...@li...>
Cc: Simon Julie Morley <sim...@go...>
Subject: Re: [Jsbsim-devel] Helicopter

Hi Bill,

Thanks for taking.

I'm currently using a mouse with a saitek throttle and so haven't ran into this issue.

I'll have to give it some thought to how to create a trim cyclic for joystick users, if the workload is considered onerous over a long flight.

I chose to use a turbine and prop combination, which I'm really happy with.

I'm happy with the flight characteristics after adapting it to have a stabilizing rotation around the lift point.

Regards

Simon.

On Sun, 25 Oct 2020, 18:08 Bill Galbraith, <bil...@gm... <mailto:bil...@gm...> > wrote:

Simon,

I had devoted some brain cells towards that idea a while ago, but never implemented it.

Imagine a point mass, with a point vertical force located above it. At 50% collective, vertical force equals weight. Cyclic tilts that vertical force fore/aft, left/right. Displacing the cyclic yields a slight loss (sine of angle) loss of lift, requiring slightly more collective.

The painful part comes when you try to fly it with a joystick. When you release the joystick, the cyclic returns back to neutral, the aircraft will slow to a hover. You basically need a joystick that has a trim lever, or allows you to reestablish the trim point.

Enough to get your brain cells excited?

Bill

From: Simon Julie Morley via Jsbsim-devel [mailto:jsb...@li... <mailto:jsb...@li...> ] 
Sent: Sunday, October 25, 2020 1:41 PM
To: Development issues <Jsb...@li... <mailto:Jsb...@li...> >
Cc: Simon Julie Morley <sim...@go... <mailto:sim...@go...> >
Subject: [Jsbsim-devel] Helicopter

Anyone here ever done one ?

Want to talk about it, share knowledge ?

Simon

  _____  

 <https://www.avg.com/internet-security> 

This email has been checked for viruses by AVG antivirus software. 
www.avg.com <https://www.avg.com/internet-security>  

_______________________________________________
Jsbsim-devel mailing list
Jsb...@li... <mailto:Jsb...@li...> 
https://lists.sourceforge.net/lists/listinfo/jsbsim-devel
_______________________________________________
The JSBSim Flight Dynamics Model project
http://www.JSBSim.org
_______________________________________________

Hi Simon

I’m just getting started again in terms of looking at JSBSim based helicopter models.

Thomas Kreitler improved the FGRotor model between 2010 – 2012.

https://github.com/JSBSim-Team/jsbsim/blob/4840a621dafe1ce64970990ddaec3e86a1c7e082/src/models/propulsion/FGRotor.cpp

He also added a fairly detailed helicopter model for the AH1S:

https://github.com/JSBSim-Team/jsbsim/tree/4840a621dafe1ce64970990ddaec3e86a1c7e082/aircraft/ah1s

In general there are very few JSBSim based helicopter models around when I last looked.

Cheers

From: Bill Galbraith <bil...@gm...>
Sent: Sunday, October 25, 2020 8:08 PM
To: 'Development issues' <jsb...@li...>
Subject: Re: [Jsbsim-devel] Helicopter

Simon,

I had devoted some brain cells towards that idea a while ago, but never implemented it.

Imagine a point mass, with a point vertical force located above it. At 50% collective, vertical force equals weight. Cyclic tilts that vertical force fore/aft, left/right. Displacing the cyclic yields a slight loss (sine of angle) loss of lift, requiring slightly more collective.

The painful part comes when you try to fly it with a joystick. When you release the joystick, the cyclic returns back to neutral, the aircraft will slow to a hover. You basically need a joystick that has a trim lever, or allows you to reestablish the trim point.

Enough to get your brain cells excited?

Bill

From: Simon Julie Morley via Jsbsim-devel [mailto:jsb...@li...]
Sent: Sunday, October 25, 2020 1:41 PM
To: Development issues <Jsb...@li...<mailto:Jsb...@li...>>
Cc: Simon Julie Morley <sim...@go...<mailto:sim...@go...>>
Subject: [Jsbsim-devel] Helicopter

Anyone here ever done one ?

Want to talk about it, share knowledge ?

Simon

Hi Sean,

To be honest I wanted to try and see if I could make a helicopter using the
prop code, because I couldn't see why not.

On Sun, 25 Oct 2020 at 21:12, Sean McLeod <se...@se...> wrote:

> Hi Simon
>
>
>
> I’m just getting started again in terms of looking at JSBSim based
> helicopter models.
>
>
>
> Thomas Kreitler improved the FGRotor model between 2010 – 2012.
>
>
>
>
> https://github.com/JSBSim-Team/jsbsim/blob/4840a621dafe1ce64970990ddaec3e86a1c7e082/src/models/propulsion/FGRotor.cpp
>
>
>
> He also added a fairly detailed helicopter model for the AH1S:
>
>
>
>
> https://github.com/JSBSim-Team/jsbsim/tree/4840a621dafe1ce64970990ddaec3e86a1c7e082/aircraft/ah1s
>
>
>
> In general there are very few JSBSim based helicopter models around when I
> last looked.
>
>
>
> Cheers
>
>
>
> *From:* Bill Galbraith <bil...@gm...>
> *Sent:* Sunday, October 25, 2020 8:08 PM
> *To:* 'Development issues' <jsb...@li...>
> *Subject:* Re: [Jsbsim-devel] Helicopter
>
>
>
> Simon,
>
>
>
> I had devoted some brain cells towards that idea a while ago, but never
> implemented it.
>
>
>
> Imagine a point mass, with a point vertical force located above it. At 50%
> collective, vertical force equals weight. Cyclic tilts that vertical force
> fore/aft, left/right. Displacing the cyclic yields a slight loss (sine of
> angle) loss of lift, requiring slightly more collective.
>
>
>
> The painful part comes when you try to fly it with a joystick. When you
> release the joystick, the cyclic returns back to neutral, the aircraft will
> slow to a hover. You basically need a joystick that has a trim lever, or
> allows you to reestablish the trim point.
>
>
>
> Enough to get your brain cells excited?
>
>
>
> Bill
>
>
>
> *From:* Simon Julie Morley via Jsbsim-devel [
> mailto:jsb...@li...
> <jsb...@li...>]
> *Sent:* Sunday, October 25, 2020 1:41 PM
> *To:* Development issues <Jsb...@li...>
> *Cc:* Simon Julie Morley <sim...@go...>
> *Subject:* [Jsbsim-devel] Helicopter
>
>
>
> Anyone here ever done one ?
>
>
>
> Want to talk about it, share knowledge ?
>
>
>
> Simon
>
>
>
>
>
>
> _______________________________________________
> Jsbsim-devel mailing list
> Jsb...@li...
> https://lists.sourceforge.net/lists/listinfo/jsbsim-devel
> _______________________________________________
> The JSBSim Flight Dynamics Model project
> http://www.JSBSim.org
> _______________________________________________
>
>

Hi Simon

I’m sure you can model a helicopter using FGPropeller etc. as a basis, but I would imagine it would be a 1st order approximation since there are a number of dynamics that FGPropeller doesn’t model compared to FGRotor, so FGRotor would more easily allow for a higher fidelity model.

Cheers

From: Simon Julie Morley via Jsbsim-devel <jsb...@li...>
Sent: Sunday, October 25, 2020 11:59 PM
To: Development issues <jsb...@li...>
Cc: Simon Julie Morley <sim...@go...>
Subject: Re: [Jsbsim-devel] Helicopter

Hi Sean,

To be honest I wanted to try and see if I could make a helicopter using the prop code, because I couldn't see why not.

On Sun, 25 Oct 2020 at 21:12, Sean McLeod <se...@se...<mailto:se...@se...>> wrote:
Hi Simon

I’m just getting started again in terms of looking at JSBSim based helicopter models.

Thomas Kreitler improved the FGRotor model between 2010 – 2012.

https://github.com/JSBSim-Team/jsbsim/blob/4840a621dafe1ce64970990ddaec3e86a1c7e082/src/models/propulsion/FGRotor.cpp

He also added a fairly detailed helicopter model for the AH1S:

https://github.com/JSBSim-Team/jsbsim/tree/4840a621dafe1ce64970990ddaec3e86a1c7e082/aircraft/ah1s

In general there are very few JSBSim based helicopter models around when I last looked.

Cheers

From: Bill Galbraith <bil...@gm...<mailto:bil...@gm...>>
Sent: Sunday, October 25, 2020 8:08 PM
To: 'Development issues' <jsb...@li...<mailto:jsb...@li...>>
Subject: Re: [Jsbsim-devel] Helicopter

Simon,

I had devoted some brain cells towards that idea a while ago, but never implemented it.

Imagine a point mass, with a point vertical force located above it. At 50% collective, vertical force equals weight. Cyclic tilts that vertical force fore/aft, left/right. Displacing the cyclic yields a slight loss (sine of angle) loss of lift, requiring slightly more collective.

The painful part comes when you try to fly it with a joystick. When you release the joystick, the cyclic returns back to neutral, the aircraft will slow to a hover. You basically need a joystick that has a trim lever, or allows you to reestablish the trim point.

Enough to get your brain cells excited?

Bill

From: Simon Julie Morley via Jsbsim-devel [mailto:jsb...@li...]
Sent: Sunday, October 25, 2020 1:41 PM
To: Development issues <Jsb...@li...<mailto:Jsb...@li...>>
Cc: Simon Julie Morley <sim...@go...<mailto:sim...@go...>>
Subject: [Jsbsim-devel] Helicopter

Anyone here ever done one ?

Want to talk about it, share knowledge ?

Simon

_______________________________________________
Jsbsim-devel mailing list
Jsb...@li...<mailto:Jsb...@li...>
https://lists.sourceforge.net/lists/listinfo/jsbsim-devel
_______________________________________________
The JSBSim Flight Dynamics Model project
http://www.JSBSim.org
_______________________________________________

I made FlightGear Robinson R-22 model using Thomas Kreitler's FGRotor. Not 
sure if its still available on-line or not. It was flyable with a complete 
set of helicopter controls. E.g. cyclic, collective and pedals.

The biggest trick to implenting a helicopter is you must consider +/-180 
degrees on alpha and -/+ 90 degrees on beta. The typical airplane model won't 
cut it. Also, FGPropeller assumes an alpha and beta of 0, so you won't see 
anything like autorotation.

Ron

On Sunday 25 October 2020 03:58:34 pm Simon Julie Morley via Jsbsim-devel 
wrote:
> Hi Sean,
>
> To be honest I wanted to try and see if I could make a helicopter using the
> prop code, because I couldn't see why not.
>
> On Sun, 25 Oct 2020 at 21:12, Sean McLeod <se...@se...> wrote:
> > Hi Simon
> >
> >
> >
> > I’m just getting started again in terms of looking at JSBSim based
> > helicopter models.
> >
> >
> >
> > Thomas Kreitler improved the FGRotor model between 2010 – 2012.
> >
> >
> >
> >
> > https://github.com/JSBSim-Team/jsbsim/blob/4840a621dafe1ce64970990ddaec3e
> >86a1c7e082/src/models/propulsion/FGRotor.cpp
> >
> >
> >
> > He also added a fairly detailed helicopter model for the AH1S:
> >
> >
> >
> >
> > https://github.com/JSBSim-Team/jsbsim/tree/4840a621dafe1ce64970990ddaec3e
> >86a1c7e082/aircraft/ah1s
> >
> >
> >
> > In general there are very few JSBSim based helicopter models around when
> > I last looked.
> >
> >
> >
> > Cheers
> >
> >
> >
> > *From:* Bill Galbraith <bil...@gm...>
> > *Sent:* Sunday, October 25, 2020 8:08 PM
> > *To:* 'Development issues' <jsb...@li...>
> > *Subject:* Re: [Jsbsim-devel] Helicopter
> >
> >
> >
> > Simon,
> >
> >
> >
> > I had devoted some brain cells towards that idea a while ago, but never
> > implemented it.
> >
> >
> >
> > Imagine a point mass, with a point vertical force located above it. At
> > 50% collective, vertical force equals weight. Cyclic tilts that vertical
> > force fore/aft, left/right. Displacing the cyclic yields a slight loss
> > (sine of angle) loss of lift, requiring slightly more collective.
> >
> >
> >
> > The painful part comes when you try to fly it with a joystick. When you
> > release the joystick, the cyclic returns back to neutral, the aircraft
> > will slow to a hover. You basically need a joystick that has a trim
> > lever, or allows you to reestablish the trim point.
> >
> >
> >
> > Enough to get your brain cells excited?
> >
> >
> >
> > Bill
> >
> >
> >
> > *From:* Simon Julie Morley via Jsbsim-devel [
> > mailto:jsb...@li...
> > <jsb...@li...>]
> > *Sent:* Sunday, October 25, 2020 1:41 PM
> > *To:* Development issues <Jsb...@li...>
> > *Cc:* Simon Julie Morley <sim...@go...>
> > *Subject:* [Jsbsim-devel] Helicopter
> >
> >
> >
> > Anyone here ever done one ?
> >
> >
> >
> > Want to talk about it, share knowledge ?
> >
> >
> >
> > Simon
> >
> >
> >
> >
> >
> >
> > _______________________________________________
> > Jsbsim-devel mailing list
> > Jsb...@li...
> > https://lists.sourceforge.net/lists/listinfo/jsbsim-devel
> > _______________________________________________
> > The JSBSim Flight Dynamics Model project
> > http://www.JSBSim.org
> > _______________________________________________

Hi Ron,

I don't do a typical plane flight model so I'm ok with the alpha and beta
calcs.

I've not found any problems with auto rotation... The object it would seem
is to spin the prop up using the air rushing through it as the helicopter
loses hight and then at the last second change it's blade angle to brake
the descent.

The alpha beta on the blade isn't an issue .

Regards

Simon

On Sun, 25 Oct 2020, 23:35 Ron Jensen, <wi...@je...> wrote:

> I made FlightGear Robinson R-22 model using Thomas Kreitler's FGRotor. Not
> sure if its still available on-line or not. It was flyable with a complete
> set of helicopter controls. E.g. cyclic, collective and pedals.
>
> The biggest trick to implenting a helicopter is you must consider +/-180
> degrees on alpha and -/+ 90 degrees on beta. The typical airplane model
> won't
> cut it. Also, FGPropeller assumes an alpha and beta of 0, so you won't see
> anything like autorotation.
>
> Ron
>
> On Sunday 25 October 2020 03:58:34 pm Simon Julie Morley via Jsbsim-devel
> wrote:
> > Hi Sean,
> >
> > To be honest I wanted to try and see if I could make a helicopter using
> the
> > prop code, because I couldn't see why not.
> >
> > On Sun, 25 Oct 2020 at 21:12, Sean McLeod <se...@se...> wrote:
> > > Hi Simon
> > >
> > >
> > >
> > > I’m just getting started again in terms of looking at JSBSim based
> > > helicopter models.
> > >
> > >
> > >
> > > Thomas Kreitler improved the FGRotor model between 2010 – 2012.
> > >
> > >
> > >
> > >
> > >
> https://github.com/JSBSim-Team/jsbsim/blob/4840a621dafe1ce64970990ddaec3e
> > >86a1c7e082/src/models/propulsion/FGRotor.cpp
> > >
> > >
> > >
> > > He also added a fairly detailed helicopter model for the AH1S:
> > >
> > >
> > >
> > >
> > >
> https://github.com/JSBSim-Team/jsbsim/tree/4840a621dafe1ce64970990ddaec3e
> > >86a1c7e082/aircraft/ah1s
> > >
> > >
> > >
> > > In general there are very few JSBSim based helicopter models around
> when
> > > I last looked.
> > >
> > >
> > >
> > > Cheers
> > >
> > >
> > >
> > > *From:* Bill Galbraith <bil...@gm...>
> > > *Sent:* Sunday, October 25, 2020 8:08 PM
> > > *To:* 'Development issues' <jsb...@li...>
> > > *Subject:* Re: [Jsbsim-devel] Helicopter
> > >
> > >
> > >
> > > Simon,
> > >
> > >
> > >
> > > I had devoted some brain cells towards that idea a while ago, but never
> > > implemented it.
> > >
> > >
> > >
> > > Imagine a point mass, with a point vertical force located above it. At
> > > 50% collective, vertical force equals weight. Cyclic tilts that
> vertical
> > > force fore/aft, left/right. Displacing the cyclic yields a slight loss
> > > (sine of angle) loss of lift, requiring slightly more collective.
> > >
> > >
> > >
> > > The painful part comes when you try to fly it with a joystick. When you
> > > release the joystick, the cyclic returns back to neutral, the aircraft
> > > will slow to a hover. You basically need a joystick that has a trim
> > > lever, or allows you to reestablish the trim point.
> > >
> > >
> > >
> > > Enough to get your brain cells excited?
> > >
> > >
> > >
> > > Bill
> > >
> > >
> > >
> > > *From:* Simon Julie Morley via Jsbsim-devel [
> > > mailto:jsb...@li...
> > > <jsb...@li...>]
> > > *Sent:* Sunday, October 25, 2020 1:41 PM
> > > *To:* Development issues <Jsb...@li...>
> > > *Cc:* Simon Julie Morley <sim...@go...>
> > > *Subject:* [Jsbsim-devel] Helicopter
> > >
> > >
> > >
> > > Anyone here ever done one ?
> > >
> > >
> > >
> > > Want to talk about it, share knowledge ?
> > >
> > >
> > >
> > > Simon
> > >
> > >
> > >
> > >
> > >
> > >
> > > _______________________________________________
> > > Jsbsim-devel mailing list
> > > Jsb...@li...
> > > https://lists.sourceforge.net/lists/listinfo/jsbsim-devel
> > > _______________________________________________
> > > The JSBSim Flight Dynamics Model project
> > > http://www.JSBSim.org
> > > _______________________________________________
>
>
>
> _______________________________________________
> Jsbsim-devel mailing list
> Jsb...@li...
> https://lists.sourceforge.net/lists/listinfo/jsbsim-devel
> _______________________________________________
> The JSBSim Flight Dynamics Model project
> http://www.JSBSim.org
> _______________________________________________
>
>

On 10/26/20 12:15 AM, Ron Jensen wrote:
> I made FlightGear Robinson R-22 model using Thomas Kreitler's FGRotor. Not
> sure if its still available on-line or not. It was flyable with a complete
> set of helicopter controls. E.g. cyclic, collective and pedals.
> 
> The biggest trick to implenting a helicopter is you must consider +/-180
> degrees on alpha and -/+ 90 degrees on beta. The typical airplane model won't
> cut it. Also, FGPropeller assumes an alpha and beta of 0, so you won't see
> anything like autorotation.

It's still available:
https://github.com/NikolaiVChr/Robinson

Erik

-- 
http://www.adalin.com
High performance audio scenegraph and sound simulation.

  yeh I have, and there's nothing in it I can't do with a propeller, and
actually there are things in the propeller code that the rotor can't do....
so using rotor is a net less...

Simon

---------- Forwarded message ---------
From: Sean McLeod <se...@se...>
Date: Mon, 26 Oct 2020 at 20:00
Subject: RE: [Jsbsim-devel] Helicopter
To: Simon Julie Morley <sim...@go...>

Hi Simon

Have you looked at the FGRotor code to see what helicopter specific stuff
it models that isn’t modeled by FGPropeller?

Cheers

*From:* Simon Julie Morley <sim...@go...>
*Sent:* Monday, October 26, 2020 5:19 PM
*To:* Sean McLeod <se...@se...>
*Subject:* Re: [Jsbsim-devel] Helicopter

Hi Sean,

I'm not sure about using prop resulting in a lesser quality or that rotor
offering greater functionality...

I remain open minded to the possibilities

Simon.

On Mon, 26 Oct 2020, 13:08 Sean McLeod, <se...@se...> wrote:

Hi Simon

I’m sure you can model a helicopter using FGPropeller etc. as a basis, but
I would imagine it would be a 1st order approximation since there are a
number of dynamics that FGPropeller doesn’t model compared to FGRotor, so
FGRotor would more easily allow for a higher fidelity model.

Cheers

*From:* Simon Julie Morley via Jsbsim-devel <
jsb...@li...>
*Sent:* Sunday, October 25, 2020 11:59 PM
*To:* Development issues <jsb...@li...>
*Cc:* Simon Julie Morley <sim...@go...>
*Subject:* Re: [Jsbsim-devel] Helicopter

Hi Sean,

To be honest I wanted to try and see if I could make a helicopter using the
prop code, because I couldn't see why not.

On Sun, 25 Oct 2020 at 21:12, Sean McLeod <se...@se...> wrote:

Hi Simon

I’m just getting started again in terms of looking at JSBSim based
helicopter models.

Thomas Kreitler improved the FGRotor model between 2010 – 2012.

https://github.com/JSBSim-Team/jsbsim/blob/4840a621dafe1ce64970990ddaec3e86a1c7e082/src/models/propulsion/FGRotor.cpp

He also added a fairly detailed helicopter model for the AH1S:

https://github.com/JSBSim-Team/jsbsim/tree/4840a621dafe1ce64970990ddaec3e86a1c7e082/aircraft/ah1s

In general there are very few JSBSim based helicopter models around when I
last looked.

Cheers

*From:* Bill Galbraith <bil...@gm...>
*Sent:* Sunday, October 25, 2020 8:08 PM
*To:* 'Development issues' <jsb...@li...>
*Subject:* Re: [Jsbsim-devel] Helicopter

Simon,

I had devoted some brain cells towards that idea a while ago, but never
implemented it.

Imagine a point mass, with a point vertical force located above it. At 50%
collective, vertical force equals weight. Cyclic tilts that vertical force
fore/aft, left/right. Displacing the cyclic yields a slight loss (sine of
angle) loss of lift, requiring slightly more collective.

The painful part comes when you try to fly it with a joystick. When you
release the joystick, the cyclic returns back to neutral, the aircraft will
slow to a hover. You basically need a joystick that has a trim lever, or
allows you to reestablish the trim point.

Enough to get your brain cells excited?

Bill

*From:* Simon Julie Morley via Jsbsim-devel [
mailto:jsb...@li...
<jsb...@li...>]
*Sent:* Sunday, October 25, 2020 1:41 PM
*To:* Development issues <Jsb...@li...>
*Cc:* Simon Julie Morley <sim...@go...>
*Subject:* [Jsbsim-devel] Helicopter

Anyone here ever done one ?

Want to talk about it, share knowledge ?

Simon

_______________________________________________
Jsbsim-devel mailing list
Jsb...@li...
https://lists.sourceforge.net/lists/listinfo/jsbsim-devel
_______________________________________________
The JSBSim Flight Dynamics Model project
http://www.JSBSim.org
_______________________________________________

Hello Simon,

I'm a bit offended by your claim -- CIT: 'there's nothing in it I can't 
do with a propeller'.

Allow me one question: how do you intend to treat the tail-rotor?

Anyway, I'm curious about your results. 'think that the propeller is 
better suited to model mid-size quad-drones and the like.

Kind Regards,

	Thomas

P.S. As for the rotor-model, two pointers for reading:

/br/ 
https://www.elsevier.com/books/bramwells-helicopter-dynamics/bramwell/978-0-08-097404-0

/sh/ Shaugnessy, J. D., Deaux, Thomas N., and Yenni, Kenneth R., 
"Development and Validation of a Piloted Simulation of a Helicopter and 
External Sling Load",  NASA TP-1285, 1979

Simon Julie Morley via Jsbsim-devel wrote:
>
>    yeh I have, and there's nothing in it I can't do with a propeller,
> and actually there are things in the propeller code that the rotor can't
> do.... so using rotor is a net less...
>
> Simon
>
> ---------- Forwarded message ---------
> From: *Sean McLeod* <se...@se... <mailto:se...@se...>>
> Date: Mon, 26 Oct 2020 at 20:00
> Subject: RE: [Jsbsim-devel] Helicopter
> To: Simon Julie Morley <sim...@go...
> <mailto:sim...@go...>>
>
>
> Hi Simon____
>
> __ __
>
> Have you looked at the FGRotor code to see what helicopter specific
> stuff it models that isnt modeled by FGPropeller?____
>
> __ __
>
> Cheers____
>
> __ __
>
> *From:* Simon Julie Morley <sim...@go...
> <mailto:sim...@go...>>
> *Sent:* Monday, October 26, 2020 5:19 PM
> *To:* Sean McLeod <se...@se... <mailto:se...@se...>>
> *Subject:* Re: [Jsbsim-devel] Helicopter____
>
> __ __
>
> Hi Sean,____
>
> __ __
>
> I'm not sure about using prop resulting in a lesser quality or that
> rotor offering greater functionality...____
>
> __ __
>
> I remain open minded to the possibilities____
>
> __ __
>
> Simon.____
>
> __ __
>
> On Mon, 26 Oct 2020, 13:08 Sean McLeod, <se...@se...
> <mailto:se...@se...>> wrote:____
>
>     Hi Simon____
>
>     ____
>
>     Im sure you can model a helicopter using FGPropeller etc. as a
>     basis, but I would imagine it would be a 1^st order approximation
>     since there are a number of dynamics that FGPropeller doesnt model
>     compared to FGRotor, so FGRotor would more easily allow for a higher
>     fidelity model.____
>
>     ____
>
>     Cheers____
>
>     ____
>
>     *From:* Simon Julie Morley via Jsbsim-devel
>     <jsb...@li...
>     <mailto:jsb...@li...>>
>     *Sent:* Sunday, October 25, 2020 11:59 PM
>     *To:* Development issues <jsb...@li...
>     <mailto:jsb...@li...>>
>     *Cc:* Simon Julie Morley <sim...@go...
>     <mailto:sim...@go...>>
>     *Subject:* Re: [Jsbsim-devel] Helicopter____
>
>     ____
>
>     Hi Sean, ____
>
>     ____
>
>     To be honest I wanted to try and see if I could make a helicopter
>     using the prop code, because I couldn't see why not.____
>
>     ____
>
>     On Sun, 25 Oct 2020 at 21:12, Sean McLeod <se...@se...
>     <mailto:se...@se...>> wrote:____
>
>         Hi Simon____
>
>         ____
>
>         Im just getting started again in terms of looking at JSBSim
>         based helicopter models.____
>
>         ____
>
>         Thomas Kreitler improved the FGRotor model between 2010  2012.____
>
>         ____
>
>         https://github.com/JSBSim-Team/jsbsim/blob/4840a621dafe1ce64970990ddaec3e86a1c7e082/src/models/propulsion/FGRotor.cpp____
>
>         ____
>
>         He also added a fairly detailed helicopter model for the AH1S:____
>
>         ____
>
>         https://github.com/JSBSim-Team/jsbsim/tree/4840a621dafe1ce64970990ddaec3e86a1c7e082/aircraft/ah1s____
>
>         ____
>
>         In general there are very few JSBSim based helicopter models
>         around when I last looked.____
>
>         ____
>
>         Cheers____
>
>         ____
>
>         *From:* Bill Galbraith <bil...@gm...
>         <mailto:bil...@gm...>>
>         *Sent:* Sunday, October 25, 2020 8:08 PM
>         *To:* 'Development issues' <jsb...@li...
>         <mailto:jsb...@li...>>
>         *Subject:* Re: [Jsbsim-devel] Helicopter____
>
>         ____
>
>         Simon,____
>
>         ____
>
>         I had devoted some brain cells towards that idea a while ago,
>         but never implemented it.____
>
>         ____
>
>         Imagine a point mass, with a point vertical force located above
>         it. At 50% collective, vertical force equals weight. Cyclic
>         tilts that vertical force fore/aft, left/right. Displacing the
>         cyclic yields a slight loss (sine of angle) loss of lift,
>         requiring slightly more collective.____
>
>         ____
>
>         The painful part comes when you try to fly it with a joystick.
>         When you release the joystick, the cyclic returns back to
>         neutral, the aircraft will slow to a hover. You basically need a
>         joystick that has a trim lever, or allows you to reestablish the
>         trim point.____
>
>         ____
>
>         Enough to get your brain cells excited?____
>
>         ____
>
>         Bill____
>
>         ____
>
>         *From:* Simon Julie Morley via Jsbsim-devel
>         [mailto:jsb...@li...]
>         *Sent:* Sunday, October 25, 2020 1:41 PM
>         *To:* Development issues <Jsb...@li...
>         <mailto:Jsb...@li...>>
>         *Cc:* Simon Julie Morley <sim...@go...
>         <mailto:sim...@go...>>
>         *Subject:* [Jsbsim-devel] Helicopter____
>
>         ____
>
>         Anyone here ever done one ?____
>
>         ____
>
>         Want to talk about it, share knowledge ?____
>
>         ____
>
>         Simon____
>
>         ____
>
>         ____
>
>         ____
>
>         _______________________________________________
>         Jsbsim-devel mailing list
>         Jsb...@li...
>         <mailto:Jsb...@li...>
>         https://lists.sourceforge.net/lists/listinfo/jsbsim-devel
>         _______________________________________________
>         The JSBSim Flight Dynamics Model project
>         http://www.JSBSim.org
>         ___________________________________________________
>
>
>
>
>
> _______________________________________________
> Jsbsim-devel mailing list
> Jsb...@li...
> https://lists.sourceforge.net/lists/listinfo/jsbsim-devel
> _______________________________________________
> The JSBSim Flight Dynamics Model project
> http://www.JSBSim.org
> _______________________________________________
>

-- 
Thomas Kreitler - Information Retrieval
kre...@mo...
49/30/8413 1702

No offense intended, it's not like I'm critising jsbsim as I'm using it.

I chose to attempt to model a helicopter by adapting the propeller code....
I shouldn't be critised for doing this.

This is my hobby, if you feel me doing something is a personal insult and
that we shouldn't talk about it, and that I shouldn't answer questions
raised to me then I'm at a loss as to the point of this forum..

Simon

On Mon, 26 Oct 2020, 22:47 Thomas, <kre...@mo...> wrote:

> Hello Simon,
>
> I'm a bit offended by your claim -- CIT: 'there's nothing in it I can't
> do with a propeller'.
>
> Allow me one question: how do you intend to treat the tail-rotor?
>
> Anyway, I'm curious about your results. 'think that the propeller is
> better suited to model mid-size quad-drones and the like.
>
> Kind Regards,
>
>         Thomas
>
> P.S. As for the rotor-model, two pointers for reading:
>
> /br/
>
> https://www.elsevier.com/books/bramwells-helicopter-dynamics/bramwell/978-0-08-097404-0
>
> /sh/ Shaugnessy, J. D., Deaux, Thomas N., and Yenni, Kenneth R.,
> "Development and Validation of a Piloted Simulation of a Helicopter and
> External Sling Load",  NASA TP-1285, 1979
>
>
> Simon Julie Morley via Jsbsim-devel wrote:
> >
> >    yeh I have, and there's nothing in it I can't do with a propeller,
> > and actually there are things in the propeller code that the rotor can't
> > do.... so using rotor is a net less...
> >
> > Simon
> >
> > ---------- Forwarded message ---------
> > From: *Sean McLeod* <se...@se... <mailto:se...@se...>>
> > Date: Mon, 26 Oct 2020 at 20:00
> > Subject: RE: [Jsbsim-devel] Helicopter
> > To: Simon Julie Morley <sim...@go...
> > <mailto:sim...@go...>>
> >
> >
> > Hi Simon____
> >
> > __ __
> >
> > Have you looked at the FGRotor code to see what helicopter specific
> > stuff it models that isn’t modeled by FGPropeller?____
> >
> > __ __
> >
> > Cheers____
> >
> > __ __
> >
> > *From:* Simon Julie Morley <sim...@go...
> > <mailto:sim...@go...>>
> > *Sent:* Monday, October 26, 2020 5:19 PM
> > *To:* Sean McLeod <se...@se... <mailto:se...@se...>>
> > *Subject:* Re: [Jsbsim-devel] Helicopter____
> >
> > __ __
> >
> > Hi Sean,____
> >
> > __ __
> >
> > I'm not sure about using prop resulting in a lesser quality or that
> > rotor offering greater functionality...____
> >
> > __ __
> >
> > I remain open minded to the possibilities____
> >
> > __ __
> >
> > Simon.____
> >
> > __ __
> >
> > On Mon, 26 Oct 2020, 13:08 Sean McLeod, <se...@se...
> > <mailto:se...@se...>> wrote:____
> >
> >     Hi Simon____
> >
> >     ____
> >
> >     I’m sure you can model a helicopter using FGPropeller etc. as a
> >     basis, but I would imagine it would be a 1^st order approximation
> >     since there are a number of dynamics that FGPropeller doesn’t model
> >     compared to FGRotor, so FGRotor would more easily allow for a higher
> >     fidelity model.____
> >
> >     ____
> >
> >     Cheers____
> >
> >     ____
> >
> >     *From:* Simon Julie Morley via Jsbsim-devel
> >     <jsb...@li...
> >     <mailto:jsb...@li...>>
> >     *Sent:* Sunday, October 25, 2020 11:59 PM
> >     *To:* Development issues <jsb...@li...
> >     <mailto:jsb...@li...>>
> >     *Cc:* Simon Julie Morley <sim...@go...
> >     <mailto:sim...@go...>>
> >     *Subject:* Re: [Jsbsim-devel] Helicopter____
> >
> >     ____
> >
> >     Hi Sean, ____
> >
> >     ____
> >
> >     To be honest I wanted to try and see if I could make a helicopter
> >     using the prop code, because I couldn't see why not.____
> >
> >     ____
> >
> >     On Sun, 25 Oct 2020 at 21:12, Sean McLeod <se...@se...
> >     <mailto:se...@se...>> wrote:____
> >
> >         Hi Simon____
> >
> >         ____
> >
> >         I’m just getting started again in terms of looking at JSBSim
> >         based helicopter models.____
> >
> >         ____
> >
> >         Thomas Kreitler improved the FGRotor model between 2010 –
> 2012.____
> >
> >         ____
> >
> >
> https://github.com/JSBSim-Team/jsbsim/blob/4840a621dafe1ce64970990ddaec3e86a1c7e082/src/models/propulsion/FGRotor.cpp____
> >
> >         ____
> >
> >         He also added a fairly detailed helicopter model for the
> AH1S:____
> >
> >         ____
> >
> >
> https://github.com/JSBSim-Team/jsbsim/tree/4840a621dafe1ce64970990ddaec3e86a1c7e082/aircraft/ah1s____
> >
> >         ____
> >
> >         In general there are very few JSBSim based helicopter models
> >         around when I last looked.____
> >
> >         ____
> >
> >         Cheers____
> >
> >         ____
> >
> >         *From:* Bill Galbraith <bil...@gm...
> >         <mailto:bil...@gm...>>
> >         *Sent:* Sunday, October 25, 2020 8:08 PM
> >         *To:* 'Development issues' <jsb...@li...
> >         <mailto:jsb...@li...>>
> >         *Subject:* Re: [Jsbsim-devel] Helicopter____
> >
> >         ____
> >
> >         Simon,____
> >
> >         ____
> >
> >         I had devoted some brain cells towards that idea a while ago,
> >         but never implemented it.____
> >
> >         ____
> >
> >         Imagine a point mass, with a point vertical force located above
> >         it. At 50% collective, vertical force equals weight. Cyclic
> >         tilts that vertical force fore/aft, left/right. Displacing the
> >         cyclic yields a slight loss (sine of angle) loss of lift,
> >         requiring slightly more collective.____
> >
> >         ____
> >
> >         The painful part comes when you try to fly it with a joystick.
> >         When you release the joystick, the cyclic returns back to
> >         neutral, the aircraft will slow to a hover. You basically need a
> >         joystick that has a trim lever, or allows you to reestablish the
> >         trim point.____
> >
> >         ____
> >
> >         Enough to get your brain cells excited?____
> >
> >         ____
> >
> >         Bill____
> >
> >         ____
> >
> >         *From:* Simon Julie Morley via Jsbsim-devel
> >         [mailto:jsb...@li...]
> >         *Sent:* Sunday, October 25, 2020 1:41 PM
> >         *To:* Development issues <Jsb...@li...
> >         <mailto:Jsb...@li...>>
> >         *Cc:* Simon Julie Morley <sim...@go...
> >         <mailto:sim...@go...>>
> >         *Subject:* [Jsbsim-devel] Helicopter____
> >
> >         ____
> >
> >         Anyone here ever done one ?____
> >
> >         ____
> >
> >         Want to talk about it, share knowledge ?____
> >
> >         ____
> >
> >         Simon____
> >
> >         ____
> >
> >         ____
> >
> >         ____
> >
> >         _______________________________________________
> >         Jsbsim-devel mailing list
> >         Jsb...@li...
> >         <mailto:Jsb...@li...>
> >         https://lists.sourceforge.net/lists/listinfo/jsbsim-devel
> >         _______________________________________________
> >         The JSBSim Flight Dynamics Model project
> >         http://www.JSBSim.org
> >         ___________________________________________________
> >
> >
> >
> >
> >
> > _______________________________________________
> > Jsbsim-devel mailing list
> > Jsb...@li...
> > https://lists.sourceforge.net/lists/listinfo/jsbsim-devel
> > _______________________________________________
> > The JSBSim Flight Dynamics Model project
> > http://www.JSBSim.org
> > _______________________________________________
> >
>
> --
> Thomas Kreitler - Information Retrieval
> kre...@mo...
> 49/30/8413 1702
>

Hi Simon,

sorry now for quoting into your response.

Simon Julie Morley wrote:
> No offense intended, it's not like I'm critising jsbsim as I'm using it.

IMHO, youre welcome

>
> I chose to attempt to model a helicopter by adapting the propeller
> code.... I shouldn't be critised for doing this.

Well, call/interpretate the critism just as 'questions' about your 
intention, or simply as advice (you are trying something new, or?), 
since I guess the people in this forum all have their individual 
'zugang' to jsbsim.

>
> This is my hobby, if you feel me doing something is a personal insult
> and that we shouldn't talk about it, and that I shouldn't answer
> questions raised to me then I'm at a loss as to the point of this forum..

No, again, feel free to exercise jsbsim -- but what's wrong about 
explaining what you like to do? My answer was a respose to your 
statement. Should I accept it, or should I pose a question? 
Alternatively, this could be a starting point for a discussion...

Thomas

>
> Simon
>
> On Mon, 26 Oct 2020, 22:47 Thomas, <kre...@mo...
> <mailto:kre...@mo...>> wrote:
>
>     Hello Simon,
>
>     I'm a bit offended by your claim -- CIT: 'there's nothing in it I can't
>     do with a propeller'.
>
>     Allow me one question: how do you intend to treat the tail-rotor?
>
>     Anyway, I'm curious about your results. 'think that the propeller is
>     better suited to model mid-size quad-drones and the like.
>
>     Kind Regards,
>
>              Thomas
>
>     P.S. As for the rotor-model, two pointers for reading:
>
>     /br/
>     https://www.elsevier.com/books/bramwells-helicopter-dynamics/bramwell/978-0-08-097404-0
>
>     /sh/ Shaugnessy, J. D., Deaux, Thomas N., and Yenni, Kenneth R.,
>     "Development and Validation of a Piloted Simulation of a Helicopter and
>     External Sling Load",  NASA TP-1285, 1979
>
>
>     Simon Julie Morley via Jsbsim-devel wrote:
>      >
>      >    yeh I have, and there's nothing in it I can't do with a propeller,
>      > and actually there are things in the propeller code that the
>     rotor can't
>      > do.... so using rotor is a net less...
>      >
>      > Simon
>      >
>      > ---------- Forwarded message ---------
>      > From: *Sean McLeod* <se...@se...
>     <mailto:se...@se...> <mailto:se...@se...
>     <mailto:se...@se...>>>
>      > Date: Mon, 26 Oct 2020 at 20:00
>      > Subject: RE: [Jsbsim-devel] Helicopter
>      > To: Simon Julie Morley <sim...@go...
>     <mailto:sim...@go...>
>      > <mailto:sim...@go...
>     <mailto:sim...@go...>>>
>      >
>      >
>      > Hi Simon____
>      >
>      > __ __
>      >
>      > Have you looked at the FGRotor code to see what helicopter specific
>      > stuff it models that isn’t modeled by FGPropeller?____
>      >
>      > __ __
>      >
>      > Cheers____
>      >
>      > __ __
>      >
>      > *From:* Simon Julie Morley <sim...@go...
>     <mailto:sim...@go...>
>      > <mailto:sim...@go...
>     <mailto:sim...@go...>>>
>      > *Sent:* Monday, October 26, 2020 5:19 PM
>      > *To:* Sean McLeod <se...@se...
>     <mailto:se...@se...> <mailto:se...@se...
>     <mailto:se...@se...>>>
>      > *Subject:* Re: [Jsbsim-devel] Helicopter____
>      >
>      > __ __
>      >
>      > Hi Sean,____
>      >
>      > __ __
>      >
>      > I'm not sure about using prop resulting in a lesser quality or that
>      > rotor offering greater functionality...____
>      >
>      > __ __
>      >
>      > I remain open minded to the possibilities____
>      >
>      > __ __
>      >
>      > Simon.____
>      >
>      > __ __
>      >
>      > On Mon, 26 Oct 2020, 13:08 Sean McLeod, <se...@se...
>     <mailto:se...@se...>
>      > <mailto:se...@se... <mailto:se...@se...>>> wrote:____
>      >
>      >     Hi Simon____
>      >
>      >     ____
>      >
>      >     I’m sure you can model a helicopter using FGPropeller etc. as a
>      >     basis, but I would imagine it would be a 1^st order approximation
>      >     since there are a number of dynamics that FGPropeller doesn’t
>     model
>      >     compared to FGRotor, so FGRotor would more easily allow for a
>     higher
>      >     fidelity model.____
>      >
>      >     ____
>      >
>      >     Cheers____
>      >
>      >     ____
>      >
>      >     *From:* Simon Julie Morley via Jsbsim-devel
>      >     <jsb...@li...
>     <mailto:jsb...@li...>
>      >     <mailto:jsb...@li...
>     <mailto:jsb...@li...>>>
>      >     *Sent:* Sunday, October 25, 2020 11:59 PM
>      >     *To:* Development issues <jsb...@li...
>     <mailto:jsb...@li...>
>      >     <mailto:jsb...@li...
>     <mailto:jsb...@li...>>>
>      >     *Cc:* Simon Julie Morley <sim...@go...
>     <mailto:sim...@go...>
>      >     <mailto:sim...@go...
>     <mailto:sim...@go...>>>
>      >     *Subject:* Re: [Jsbsim-devel] Helicopter____
>      >
>      >     ____
>      >
>      >     Hi Sean, ____
>      >
>      >     ____
>      >
>      >     To be honest I wanted to try and see if I could make a helicopter
>      >     using the prop code, because I couldn't see why not.____
>      >
>      >     ____
>      >
>      >     On Sun, 25 Oct 2020 at 21:12, Sean McLeod
>     <se...@se... <mailto:se...@se...>
>      >     <mailto:se...@se... <mailto:se...@se...>>>
>     wrote:____
>      >
>      >         Hi Simon____
>      >
>      >         ____
>      >
>      >         I’m just getting started again in terms of looking at JSBSim
>      >         based helicopter models.____
>      >
>      >         ____
>      >
>      >         Thomas Kreitler improved the FGRotor model between 2010 –
>     2012.____
>      >
>      >         ____
>      >
>      >
>     https://github.com/JSBSim-Team/jsbsim/blob/4840a621dafe1ce64970990ddaec3e86a1c7e082/src/models/propulsion/FGRotor.cpp____
>      >
>      >         ____
>      >
>      >         He also added a fairly detailed helicopter model for the
>     AH1S:____
>      >
>      >         ____
>      >
>      >
>     https://github.com/JSBSim-Team/jsbsim/tree/4840a621dafe1ce64970990ddaec3e86a1c7e082/aircraft/ah1s____
>      >
>      >         ____
>      >
>      >         In general there are very few JSBSim based helicopter models
>      >         around when I last looked.____
>      >
>      >         ____
>      >
>      >         Cheers____
>      >
>      >         ____
>      >
>      >         *From:* Bill Galbraith <bil...@gm...
>     <mailto:bil...@gm...>
>      >         <mailto:bil...@gm...
>     <mailto:bil...@gm...>>>
>      >         *Sent:* Sunday, October 25, 2020 8:08 PM
>      >         *To:* 'Development issues'
>     <jsb...@li...
>     <mailto:jsb...@li...>
>      >         <mailto:jsb...@li...
>     <mailto:jsb...@li...>>>
>      >         *Subject:* Re: [Jsbsim-devel] Helicopter____
>      >
>      >         ____
>      >
>      >         Simon,____
>      >
>      >         ____
>      >
>      >         I had devoted some brain cells towards that idea a while ago,
>      >         but never implemented it.____
>      >
>      >         ____
>      >
>      >         Imagine a point mass, with a point vertical force located
>     above
>      >         it. At 50% collective, vertical force equals weight. Cyclic
>      >         tilts that vertical force fore/aft, left/right.
>     Displacing the
>      >         cyclic yields a slight loss (sine of angle) loss of lift,
>      >         requiring slightly more collective.____
>      >
>      >         ____
>      >
>      >         The painful part comes when you try to fly it with a
>     joystick.
>      >         When you release the joystick, the cyclic returns back to
>      >         neutral, the aircraft will slow to a hover. You basically
>     need a
>      >         joystick that has a trim lever, or allows you to
>     reestablish the
>      >         trim point.____
>      >
>      >         ____
>      >
>      >         Enough to get your brain cells excited?____
>      >
>      >         ____
>      >
>      >         Bill____
>      >
>      >         ____
>      >
>      >         *From:* Simon Julie Morley via Jsbsim-devel
>      >         [mailto:jsb...@li...
>     <mailto:jsb...@li...>]
>      >         *Sent:* Sunday, October 25, 2020 1:41 PM
>      >         *To:* Development issues
>     <Jsb...@li...
>     <mailto:Jsb...@li...>
>      >         <mailto:Jsb...@li...
>     <mailto:Jsb...@li...>>>
>      >         *Cc:* Simon Julie Morley <sim...@go...
>     <mailto:sim...@go...>
>      >         <mailto:sim...@go...
>     <mailto:sim...@go...>>>
>      >         *Subject:* [Jsbsim-devel] Helicopter____
>      >
>      >         ____
>      >
>      >         Anyone here ever done one ?____
>      >
>      >         ____
>      >
>      >         Want to talk about it, share knowledge ?____
>      >
>      >         ____
>      >
>      >         Simon____
>      >
>      >         ____
>      >
>      >         ____
>      >
>      >         ____
>      >
>      >         _______________________________________________
>      >         Jsbsim-devel mailing list
>      > Jsb...@li...
>     <mailto:Jsb...@li...>
>      >         <mailto:Jsb...@li...
>     <mailto:Jsb...@li...>>
>      > https://lists.sourceforge.net/lists/listinfo/jsbsim-devel
>      >         _______________________________________________
>      >         The JSBSim Flight Dynamics Model project
>      > http://www.JSBSim.org
>      >         ___________________________________________________
>      >
>      >
>      >
>      >
>      >
>      > _______________________________________________
>      > Jsbsim-devel mailing list
>      > Jsb...@li...
>     <mailto:Jsb...@li...>
>      > https://lists.sourceforge.net/lists/listinfo/jsbsim-devel
>      > _______________________________________________
>      > The JSBSim Flight Dynamics Model project
>      > http://www.JSBSim.org
>      > _______________________________________________
>      >
>
>     --
>     Thomas Kreitler - Information Retrieval
>     kre...@mo... <mailto:kre...@mo...>
>     49/30/8413 1702
>

-- 
Thomas Kreitler - Information Retrieval
kre...@mo...
49/30/8413 1702

Ok to answer the question about the tail rotor.

It's a force that produces a moment equal and opposite to the main rotor
n_moment. The collective increases or reduces this force value by up to 10%

On Tue, 27 Oct 2020, 00:56 Thomas, <kre...@mo...> wrote:

> Hi Simon,
>
> sorry now for quoting into your response.
>
> Simon Julie Morley wrote:
> > No offense intended, it's not like I'm critising jsbsim as I'm using it.
>
> IMHO, youre welcome
>
> >
> > I chose to attempt to model a helicopter by adapting the propeller
> > code.... I shouldn't be critised for doing this.
>
> Well, call/interpretate the critism just as 'questions' about your
> intention, or simply as advice (you are trying something new, or?),
> since I guess the people in this forum all have their individual
> 'zugang' to jsbsim.
>
> >
> > This is my hobby, if you feel me doing something is a personal insult
> > and that we shouldn't talk about it, and that I shouldn't answer
> > questions raised to me then I'm at a loss as to the point of this forum..
>
> No, again, feel free to exercise jsbsim -- but what's wrong about
> explaining what you like to do? My answer was a respose to your
> statement. Should I accept it, or should I pose a question?
> Alternatively, this could be a starting point for a discussion...
>
> Thomas
>
>
> >
> > Simon
> >
> > On Mon, 26 Oct 2020, 22:47 Thomas, <kre...@mo...
> > <mailto:kre...@mo...>> wrote:
> >
> >     Hello Simon,
> >
> >     I'm a bit offended by your claim -- CIT: 'there's nothing in it I
> can't
> >     do with a propeller'.
> >
> >     Allow me one question: how do you intend to treat the tail-rotor?
> >
> >     Anyway, I'm curious about your results. 'think that the propeller is
> >     better suited to model mid-size quad-drones and the like.
> >
> >     Kind Regards,
> >
> >              Thomas
> >
> >     P.S. As for the rotor-model, two pointers for reading:
> >
> >     /br/
> >
> https://www.elsevier.com/books/bramwells-helicopter-dynamics/bramwell/978-0-08-097404-0
> >
> >     /sh/ Shaugnessy, J. D., Deaux, Thomas N., and Yenni, Kenneth R.,
> >     "Development and Validation of a Piloted Simulation of a Helicopter
> and
> >     External Sling Load",  NASA TP-1285, 1979
> >
> >
> >     Simon Julie Morley via Jsbsim-devel wrote:
> >      >
> >      >    yeh I have, and there's nothing in it I can't do with a
> propeller,
> >      > and actually there are things in the propeller code that the
> >     rotor can't
> >      > do.... so using rotor is a net less...
> >      >
> >      > Simon
> >      >
> >      > ---------- Forwarded message ---------
> >      > From: *Sean McLeod* <se...@se...
> >     <mailto:se...@se...> <mailto:se...@se...
> >     <mailto:se...@se...>>>
> >      > Date: Mon, 26 Oct 2020 at 20:00
> >      > Subject: RE: [Jsbsim-devel] Helicopter
> >      > To: Simon Julie Morley <sim...@go...
> >     <mailto:sim...@go...>
> >      > <mailto:sim...@go...
> >     <mailto:sim...@go...>>>
> >      >
> >      >
> >      > Hi Simon____
> >      >
> >      > __ __
> >      >
> >      > Have you looked at the FGRotor code to see what helicopter
> specific
> >      > stuff it models that isn’t modeled by FGPropeller?____
> >      >
> >      > __ __
> >      >
> >      > Cheers____
> >      >
> >      > __ __
> >      >
> >      > *From:* Simon Julie Morley <sim...@go...
> >     <mailto:sim...@go...>
> >      > <mailto:sim...@go...
> >     <mailto:sim...@go...>>>
> >      > *Sent:* Monday, October 26, 2020 5:19 PM
> >      > *To:* Sean McLeod <se...@se...
> >     <mailto:se...@se...> <mailto:se...@se...
> >     <mailto:se...@se...>>>
> >      > *Subject:* Re: [Jsbsim-devel] Helicopter____
> >      >
> >      > __ __
> >      >
> >      > Hi Sean,____
> >      >
> >      > __ __
> >      >
> >      > I'm not sure about using prop resulting in a lesser quality or
> that
> >      > rotor offering greater functionality...____
> >      >
> >      > __ __
> >      >
> >      > I remain open minded to the possibilities____
> >      >
> >      > __ __
> >      >
> >      > Simon.____
> >      >
> >      > __ __
> >      >
> >      > On Mon, 26 Oct 2020, 13:08 Sean McLeod, <se...@se...
> >     <mailto:se...@se...>
> >      > <mailto:se...@se... <mailto:se...@se...>>>
> wrote:____
> >      >
> >      >     Hi Simon____
> >      >
> >      >     ____
> >      >
> >      >     I’m sure you can model a helicopter using FGPropeller etc. as
> a
> >      >     basis, but I would imagine it would be a 1^st order
> approximation
> >      >     since there are a number of dynamics that FGPropeller doesn’t
> >     model
> >      >     compared to FGRotor, so FGRotor would more easily allow for a
> >     higher
> >      >     fidelity model.____
> >      >
> >      >     ____
> >      >
> >      >     Cheers____
> >      >
> >      >     ____
> >      >
> >      >     *From:* Simon Julie Morley via Jsbsim-devel
> >      >     <jsb...@li...
> >     <mailto:jsb...@li...>
> >      >     <mailto:jsb...@li...
> >     <mailto:jsb...@li...>>>
> >      >     *Sent:* Sunday, October 25, 2020 11:59 PM
> >      >     *To:* Development issues <jsb...@li...
> >     <mailto:jsb...@li...>
> >      >     <mailto:jsb...@li...
> >     <mailto:jsb...@li...>>>
> >      >     *Cc:* Simon Julie Morley <sim...@go...
> >     <mailto:sim...@go...>
> >      >     <mailto:sim...@go...
> >     <mailto:sim...@go...>>>
> >      >     *Subject:* Re: [Jsbsim-devel] Helicopter____
> >      >
> >      >     ____
> >      >
> >      >     Hi Sean, ____
> >      >
> >      >     ____
> >      >
> >      >     To be honest I wanted to try and see if I could make a
> helicopter
> >      >     using the prop code, because I couldn't see why not.____
> >      >
> >      >     ____
> >      >
> >      >     On Sun, 25 Oct 2020 at 21:12, Sean McLeod
> >     <se...@se... <mailto:se...@se...>
> >      >     <mailto:se...@se... <mailto:se...@se...>>>
> >     wrote:____
> >      >
> >      >         Hi Simon____
> >      >
> >      >         ____
> >      >
> >      >         I’m just getting started again in terms of looking at
> JSBSim
> >      >         based helicopter models.____
> >      >
> >      >         ____
> >      >
> >      >         Thomas Kreitler improved the FGRotor model between 2010 –
> >     2012.____
> >      >
> >      >         ____
> >      >
> >      >
> >
> https://github.com/JSBSim-Team/jsbsim/blob/4840a621dafe1ce64970990ddaec3e86a1c7e082/src/models/propulsion/FGRotor.cpp____
> >      >
> >      >         ____
> >      >
> >      >         He also added a fairly detailed helicopter model for the
> >     AH1S:____
> >      >
> >      >         ____
> >      >
> >      >
> >
> https://github.com/JSBSim-Team/jsbsim/tree/4840a621dafe1ce64970990ddaec3e86a1c7e082/aircraft/ah1s____
> >      >
> >      >         ____
> >      >
> >      >         In general there are very few JSBSim based helicopter
> models
> >      >         around when I last looked.____
> >      >
> >      >         ____
> >      >
> >      >         Cheers____
> >      >
> >      >         ____
> >      >
> >      >         *From:* Bill Galbraith <bil...@gm...
> >     <mailto:bil...@gm...>
> >      >         <mailto:bil...@gm...
> >     <mailto:bil...@gm...>>>
> >      >         *Sent:* Sunday, October 25, 2020 8:08 PM
> >      >         *To:* 'Development issues'
> >     <jsb...@li...
> >     <mailto:jsb...@li...>
> >      >         <mailto:jsb...@li...
> >     <mailto:jsb...@li...>>>
> >      >         *Subject:* Re: [Jsbsim-devel] Helicopter____
> >      >
> >      >         ____
> >      >
> >      >         Simon,____
> >      >
> >      >         ____
> >      >
> >      >         I had devoted some brain cells towards that idea a while
> ago,
> >      >         but never implemented it.____
> >      >
> >      >         ____
> >      >
> >      >         Imagine a point mass, with a point vertical force located
> >     above
> >      >         it. At 50% collective, vertical force equals weight.
> Cyclic
> >      >         tilts that vertical force fore/aft, left/right.
> >     Displacing the
> >      >         cyclic yields a slight loss (sine of angle) loss of lift,
> >      >         requiring slightly more collective.____
> >      >
> >      >         ____
> >      >
> >      >         The painful part comes when you try to fly it with a
> >     joystick.
> >      >         When you release the joystick, the cyclic returns back to
> >      >         neutral, the aircraft will slow to a hover. You basically
> >     need a
> >      >         joystick that has a trim lever, or allows you to
> >     reestablish the
> >      >         trim point.____
> >      >
> >      >         ____
> >      >
> >      >         Enough to get your brain cells excited?____
> >      >
> >      >         ____
> >      >
> >      >         Bill____
> >      >
> >      >         ____
> >      >
> >      >         *From:* Simon Julie Morley via Jsbsim-devel
> >      >         [mailto:jsb...@li...
> >     <mailto:jsb...@li...>]
> >      >         *Sent:* Sunday, October 25, 2020 1:41 PM
> >      >         *To:* Development issues
> >     <Jsb...@li...
> >     <mailto:Jsb...@li...>
> >      >         <mailto:Jsb...@li...
> >     <mailto:Jsb...@li...>>>
> >      >         *Cc:* Simon Julie Morley <sim...@go...
> >     <mailto:sim...@go...>
> >      >         <mailto:sim...@go...
> >     <mailto:sim...@go...>>>
> >      >         *Subject:* [Jsbsim-devel] Helicopter____
> >      >
> >      >         ____
> >      >
> >      >         Anyone here ever done one ?____
> >      >
> >      >         ____
> >      >
> >      >         Want to talk about it, share knowledge ?____
> >      >
> >      >         ____
> >      >
> >      >         Simon____
> >      >
> >      >         ____
> >      >
> >      >         ____
> >      >
> >      >         ____
> >      >
> >      >         _______________________________________________
> >      >         Jsbsim-devel mailing list
> >      > Jsb...@li...
> >     <mailto:Jsb...@li...>
> >      >         <mailto:Jsb...@li...
> >     <mailto:Jsb...@li...>>
> >      > https://lists.sourceforge.net/lists/listinfo/jsbsim-devel
> >      >         _______________________________________________
> >      >         The JSBSim Flight Dynamics Model project
> >      > http://www.JSBSim.org
> >      >         ___________________________________________________
> >      >
> >      >
> >      >
> >      >
> >      >
> >      > _______________________________________________
> >      > Jsbsim-devel mailing list
> >      > Jsb...@li...
> >     <mailto:Jsb...@li...>
> >      > https://lists.sourceforge.net/lists/listinfo/jsbsim-devel
> >      > _______________________________________________
> >      > The JSBSim Flight Dynamics Model project
> >      > http://www.JSBSim.org
> >      > _______________________________________________
> >      >
> >
> >     --
> >     Thomas Kreitler - Information Retrieval
> >     kre...@mo... <mailto:kre...@mo...>
> >     49/30/8413 1702
> >
>
> --
> Thomas Kreitler - Information Retrieval
> kre...@mo...
> 49/30/8413 1702
>

Out of curiosity, I've had to create a pendulum damping force as a
helicopter rotates around it's rotor, as opposed to it's CoG.

Did anyone else have this issue, and how did you resolve it.

Simon

On Tue, 27 Oct 2020 at 09:40, Simon Julie Morley <
sim...@go...> wrote:

> Ok to answer the question about the tail rotor.
>
> It's a force that produces a moment equal and opposite to the main rotor
> n_moment. The collective increases or reduces this force value by up to 10%
>
> On Tue, 27 Oct 2020, 00:56 Thomas, <kre...@mo...> wrote:
>
>> Hi Simon,
>>
>> sorry now for quoting into your response.
>>
>> Simon Julie Morley wrote:
>> > No offense intended, it's not like I'm critising jsbsim as I'm using it.
>>
>> IMHO, youre welcome
>>
>> >
>> > I chose to attempt to model a helicopter by adapting the propeller
>> > code.... I shouldn't be critised for doing this.
>>
>> Well, call/interpretate the critism just as 'questions' about your
>> intention, or simply as advice (you are trying something new, or?),
>> since I guess the people in this forum all have their individual
>> 'zugang' to jsbsim.
>>
>> >
>> > This is my hobby, if you feel me doing something is a personal insult
>> > and that we shouldn't talk about it, and that I shouldn't answer
>> > questions raised to me then I'm at a loss as to the point of this
>> forum..
>>
>> No, again, feel free to exercise jsbsim -- but what's wrong about
>> explaining what you like to do? My answer was a respose to your
>> statement. Should I accept it, or should I pose a question?
>> Alternatively, this could be a starting point for a discussion...
>>
>> Thomas
>>
>>
>> >
>> > Simon
>> >
>> > On Mon, 26 Oct 2020, 22:47 Thomas, <kre...@mo...
>> > <mailto:kre...@mo...>> wrote:
>> >
>> >     Hello Simon,
>> >
>> >     I'm a bit offended by your claim -- CIT: 'there's nothing in it I
>> can't
>> >     do with a propeller'.
>> >
>> >     Allow me one question: how do you intend to treat the tail-rotor?
>> >
>> >     Anyway, I'm curious about your results. 'think that the propeller is
>> >     better suited to model mid-size quad-drones and the like.
>> >
>> >     Kind Regards,
>> >
>> >              Thomas
>> >
>> >     P.S. As for the rotor-model, two pointers for reading:
>> >
>> >     /br/
>> >
>> https://www.elsevier.com/books/bramwells-helicopter-dynamics/bramwell/978-0-08-097404-0
>> >
>> >     /sh/ Shaugnessy, J. D., Deaux, Thomas N., and Yenni, Kenneth R.,
>> >     "Development and Validation of a Piloted Simulation of a Helicopter
>> and
>> >     External Sling Load",  NASA TP-1285, 1979
>> >
>> >
>> >     Simon Julie Morley via Jsbsim-devel wrote:
>> >      >
>> >      >    yeh I have, and there's nothing in it I can't do with a
>> propeller,
>> >      > and actually there are things in the propeller code that the
>> >     rotor can't
>> >      > do.... so using rotor is a net less...
>> >      >
>> >      > Simon
>> >      >
>> >      > ---------- Forwarded message ---------
>> >      > From: *Sean McLeod* <se...@se...
>> >     <mailto:se...@se...> <mailto:se...@se...
>> >     <mailto:se...@se...>>>
>> >      > Date: Mon, 26 Oct 2020 at 20:00
>> >      > Subject: RE: [Jsbsim-devel] Helicopter
>> >      > To: Simon Julie Morley <sim...@go...
>> >     <mailto:sim...@go...>
>> >      > <mailto:sim...@go...
>> >     <mailto:sim...@go...>>>
>> >      >
>> >      >
>> >      > Hi Simon____
>> >      >
>> >      > __ __
>> >      >
>> >      > Have you looked at the FGRotor code to see what helicopter
>> specific
>> >      > stuff it models that isn’t modeled by FGPropeller?____
>> >      >
>> >      > __ __
>> >      >
>> >      > Cheers____
>> >      >
>> >      > __ __
>> >      >
>> >      > *From:* Simon Julie Morley <sim...@go...
>> >     <mailto:sim...@go...>
>> >      > <mailto:sim...@go...
>> >     <mailto:sim...@go...>>>
>> >      > *Sent:* Monday, October 26, 2020 5:19 PM
>> >      > *To:* Sean McLeod <se...@se...
>> >     <mailto:se...@se...> <mailto:se...@se...
>> >     <mailto:se...@se...>>>
>> >      > *Subject:* Re: [Jsbsim-devel] Helicopter____
>> >      >
>> >      > __ __
>> >      >
>> >      > Hi Sean,____
>> >      >
>> >      > __ __
>> >      >
>> >      > I'm not sure about using prop resulting in a lesser quality or
>> that
>> >      > rotor offering greater functionality...____
>> >      >
>> >      > __ __
>> >      >
>> >      > I remain open minded to the possibilities____
>> >      >
>> >      > __ __
>> >      >
>> >      > Simon.____
>> >      >
>> >      > __ __
>> >      >
>> >      > On Mon, 26 Oct 2020, 13:08 Sean McLeod, <se...@se...
>> >     <mailto:se...@se...>
>> >      > <mailto:se...@se... <mailto:se...@se...>>>
>> wrote:____
>> >      >
>> >      >     Hi Simon____
>> >      >
>> >      >     ____
>> >      >
>> >      >     I’m sure you can model a helicopter using FGPropeller etc.
>> as a
>> >      >     basis, but I would imagine it would be a 1^st order
>> approximation
>> >      >     since there are a number of dynamics that FGPropeller doesn’t
>> >     model
>> >      >     compared to FGRotor, so FGRotor would more easily allow for a
>> >     higher
>> >      >     fidelity model.____
>> >      >
>> >      >     ____
>> >      >
>> >      >     Cheers____
>> >      >
>> >      >     ____
>> >      >
>> >      >     *From:* Simon Julie Morley via Jsbsim-devel
>> >      >     <jsb...@li...
>> >     <mailto:jsb...@li...>
>> >      >     <mailto:jsb...@li...
>> >     <mailto:jsb...@li...>>>
>> >      >     *Sent:* Sunday, October 25, 2020 11:59 PM
>> >      >     *To:* Development issues <jsb...@li...
>> >     <mailto:jsb...@li...>
>> >      >     <mailto:jsb...@li...
>> >     <mailto:jsb...@li...>>>
>> >      >     *Cc:* Simon Julie Morley <sim...@go...
>> >     <mailto:sim...@go...>
>> >      >     <mailto:sim...@go...
>> >     <mailto:sim...@go...>>>
>> >      >     *Subject:* Re: [Jsbsim-devel] Helicopter____
>> >      >
>> >      >     ____
>> >      >
>> >      >     Hi Sean, ____
>> >      >
>> >      >     ____
>> >      >
>> >      >     To be honest I wanted to try and see if I could make a
>> helicopter
>> >      >     using the prop code, because I couldn't see why not.____
>> >      >
>> >      >     ____
>> >      >
>> >      >     On Sun, 25 Oct 2020 at 21:12, Sean McLeod
>> >     <se...@se... <mailto:se...@se...>
>> >      >     <mailto:se...@se... <mailto:se...@se...>>>
>> >     wrote:____
>> >      >
>> >      >         Hi Simon____
>> >      >
>> >      >         ____
>> >      >
>> >      >         I’m just getting started again in terms of looking at
>> JSBSim
>> >      >         based helicopter models.____
>> >      >
>> >      >         ____
>> >      >
>> >      >         Thomas Kreitler improved the FGRotor model between 2010 –
>> >     2012.____
>> >      >
>> >      >         ____
>> >      >
>> >      >
>> >
>> https://github.com/JSBSim-Team/jsbsim/blob/4840a621dafe1ce64970990ddaec3e86a1c7e082/src/models/propulsion/FGRotor.cpp____
>> >      >
>> >      >         ____
>> >      >
>> >      >         He also added a fairly detailed helicopter model for the
>> >     AH1S:____
>> >      >
>> >      >         ____
>> >      >
>> >      >
>> >
>> https://github.com/JSBSim-Team/jsbsim/tree/4840a621dafe1ce64970990ddaec3e86a1c7e082/aircraft/ah1s____
>> >      >
>> >      >         ____
>> >      >
>> >      >         In general there are very few JSBSim based helicopter
>> models
>> >      >         around when I last looked.____
>> >      >
>> >      >         ____
>> >      >
>> >      >         Cheers____
>> >      >
>> >      >         ____
>> >      >
>> >      >         *From:* Bill Galbraith <bil...@gm...
>> >     <mailto:bil...@gm...>
>> >      >         <mailto:bil...@gm...
>> >     <mailto:bil...@gm...>>>
>> >      >         *Sent:* Sunday, October 25, 2020 8:08 PM
>> >      >         *To:* 'Development issues'
>> >     <jsb...@li...
>> >     <mailto:jsb...@li...>
>> >      >         <mailto:jsb...@li...
>> >     <mailto:jsb...@li...>>>
>> >      >         *Subject:* Re: [Jsbsim-devel] Helicopter____
>> >      >
>> >      >         ____
>> >      >
>> >      >         Simon,____
>> >      >
>> >      >         ____
>> >      >
>> >      >         I had devoted some brain cells towards that idea a while
>> ago,
>> >      >         but never implemented it.____
>> >      >
>> >      >         ____
>> >      >
>> >      >         Imagine a point mass, with a point vertical force located
>> >     above
>> >      >         it. At 50% collective, vertical force equals weight.
>> Cyclic
>> >      >         tilts that vertical force fore/aft, left/right.
>> >     Displacing the
>> >      >         cyclic yields a slight loss (sine of angle) loss of lift,
>> >      >         requiring slightly more collective.____
>> >      >
>> >      >         ____
>> >      >
>> >      >         The painful part comes when you try to fly it with a
>> >     joystick.
>> >      >         When you release the joystick, the cyclic returns back to
>> >      >         neutral, the aircraft will slow to a hover. You basically
>> >     need a
>> >      >         joystick that has a trim lever, or allows you to
>> >     reestablish the
>> >      >         trim point.____
>> >      >
>> >      >         ____
>> >      >
>> >      >         Enough to get your brain cells excited?____
>> >      >
>> >      >         ____
>> >      >
>> >      >         Bill____
>> >      >
>> >      >         ____
>> >      >
>> >      >         *From:* Simon Julie Morley via Jsbsim-devel
>> >      >         [mailto:jsb...@li...
>> >     <mailto:jsb...@li...>]
>> >      >         *Sent:* Sunday, October 25, 2020 1:41 PM
>> >      >         *To:* Development issues
>> >     <Jsb...@li...
>> >     <mailto:Jsb...@li...>
>> >      >         <mailto:Jsb...@li...
>> >     <mailto:Jsb...@li...>>>
>> >      >         *Cc:* Simon Julie Morley <sim...@go...
>> >     <mailto:sim...@go...>
>> >      >         <mailto:sim...@go...
>> >     <mailto:sim...@go...>>>
>> >      >         *Subject:* [Jsbsim-devel] Helicopter____
>> >      >
>> >      >         ____
>> >      >
>> >      >         Anyone here ever done one ?____
>> >      >
>> >      >         ____
>> >      >
>> >      >         Want to talk about it, share knowledge ?____
>> >      >
>> >      >         ____
>> >      >
>> >      >         Simon____
>> >      >
>> >      >         ____
>> >      >
>> >      >         ____
>> >      >
>> >      >         ____
>> >      >
>> >      >         _______________________________________________
>> >      >         Jsbsim-devel mailing list
>> >      > Jsb...@li...
>> >     <mailto:Jsb...@li...>
>> >      >         <mailto:Jsb...@li...
>> >     <mailto:Jsb...@li...>>
>> >      > https://lists.sourceforge.net/lists/listinfo/jsbsim-devel
>> >      >         _______________________________________________
>> >      >         The JSBSim Flight Dynamics Model project
>> >      > http://www.JSBSim.org
>> >      >         ___________________________________________________
>> >      >
>> >      >
>> >      >
>> >      >
>> >      >
>> >      > _______________________________________________
>> >      > Jsbsim-devel mailing list
>> >      > Jsb...@li...
>> >     <mailto:Jsb...@li...>
>> >      > https://lists.sourceforge.net/lists/listinfo/jsbsim-devel
>> >      > _______________________________________________
>> >      > The JSBSim Flight Dynamics Model project
>> >      > http://www.JSBSim.org
>> >      > _______________________________________________
>> >      >
>> >
>> >     --
>> >     Thomas Kreitler - Information Retrieval
>> >     kre...@mo... <mailto:kre...@mo...>
>> >     49/30/8413 1702
>> >
>>
>> --
>> Thomas Kreitler - Information Retrieval
>> kre...@mo...
>> 49/30/8413 1702
>>
>

Hi Simon

Are you adding code to FGPropeller to implement some of the functionality that is currently in FGRotor but not in FGPropeller currently?

Are there some aspects of FGRotor’s functionality that you’re ignoring because you don’t think they’re useful for your needs?

What things did you notice in FGPropeller that FGRotor can’t currently do? Could potentially be useful to add them to FGRotor for users of FGRotor.

What’s quite useful is Thomas references the equations etc. that his code is based on, e.g.

// Flapping angles relative to control axes /SH79/ eqn(32)
void FGRotor::calc_flapping_angles(double theta_0, const FGColumnVector3 &pqr_fus_w)

    <dt>/SH79/</dt><dd>Shaugnessy, J. D., Deaux, Thomas N., and Yenni, Kenneth R.,
              "Development and Validation of a Piloted Simulation of a
              Helicopter and External Sling Load",  NASA TP-1285, 1979.</dd>

https://ntrs.nasa.gov/citations/19790005912

I’m currently using FGotor for the helicopter models I’m working on so I’d be interested to know what you see as the pros and cons of using FGRotor versus FGPropeller.

Cheers

From: Simon Julie Morley via Jsbsim-devel <jsb...@li...>
Sent: Monday, October 26, 2020 10:09 PM
To: Development issues <Jsb...@li...>
Cc: Simon Julie Morley <sim...@go...>
Subject: [Jsbsim-devel] Fwd: Helicopter

  yeh I have, and there's nothing in it I can't do with a propeller, and actually there are things in the propeller code that the rotor can't do.... so using rotor is a net less...

Simon

---------- Forwarded message ---------
From: Sean McLeod <se...@se...<mailto:se...@se...>>
Date: Mon, 26 Oct 2020 at 20:00
Subject: RE: [Jsbsim-devel] Helicopter
To: Simon Julie Morley <sim...@go...<mailto:sim...@go...>>

Hi Simon

Have you looked at the FGRotor code to see what helicopter specific stuff it models that isn’t modeled by FGPropeller?

Cheers

From: Simon Julie Morley <sim...@go...<mailto:sim...@go...>>
Sent: Monday, October 26, 2020 5:19 PM
To: Sean McLeod <se...@se...<mailto:se...@se...>>
Subject: Re: [Jsbsim-devel] Helicopter

Hi Sean,

I'm not sure about using prop resulting in a lesser quality or that rotor offering greater functionality...

I remain open minded to the possibilities

Simon.

On Mon, 26 Oct 2020, 13:08 Sean McLeod, <se...@se...<mailto:se...@se...>> wrote:
Hi Simon

I’m sure you can model a helicopter using FGPropeller etc. as a basis, but I would imagine it would be a 1st order approximation since there are a number of dynamics that FGPropeller doesn’t model compared to FGRotor, so FGRotor would more easily allow for a higher fidelity model.

Cheers

From: Simon Julie Morley via Jsbsim-devel <jsb...@li...<mailto:jsb...@li...>>
Sent: Sunday, October 25, 2020 11:59 PM
To: Development issues <jsb...@li...<mailto:jsb...@li...>>
Cc: Simon Julie Morley <sim...@go...<mailto:sim...@go...>>
Subject: Re: [Jsbsim-devel] Helicopter

Hi Sean,

To be honest I wanted to try and see if I could make a helicopter using the prop code, because I couldn't see why not.

On Sun, 25 Oct 2020 at 21:12, Sean McLeod <se...@se...<mailto:se...@se...>> wrote:
Hi Simon

I’m just getting started again in terms of looking at JSBSim based helicopter models.

Thomas Kreitler improved the FGRotor model between 2010 – 2012.

https://github.com/JSBSim-Team/jsbsim/blob/4840a621dafe1ce64970990ddaec3e86a1c7e082/src/models/propulsion/FGRotor.cpp

He also added a fairly detailed helicopter model for the AH1S:

https://github.com/JSBSim-Team/jsbsim/tree/4840a621dafe1ce64970990ddaec3e86a1c7e082/aircraft/ah1s

In general there are very few JSBSim based helicopter models around when I last looked.

Cheers

From: Bill Galbraith <bil...@gm...<mailto:bil...@gm...>>
Sent: Sunday, October 25, 2020 8:08 PM
To: 'Development issues' <jsb...@li...<mailto:jsb...@li...>>
Subject: Re: [Jsbsim-devel] Helicopter

Simon,

I had devoted some brain cells towards that idea a while ago, but never implemented it.

Imagine a point mass, with a point vertical force located above it. At 50% collective, vertical force equals weight. Cyclic tilts that vertical force fore/aft, left/right. Displacing the cyclic yields a slight loss (sine of angle) loss of lift, requiring slightly more collective.

The painful part comes when you try to fly it with a joystick. When you release the joystick, the cyclic returns back to neutral, the aircraft will slow to a hover. You basically need a joystick that has a trim lever, or allows you to reestablish the trim point.

Enough to get your brain cells excited?

Bill

From: Simon Julie Morley via Jsbsim-devel [mailto:jsb...@li...]
Sent: Sunday, October 25, 2020 1:41 PM
To: Development issues <Jsb...@li...<mailto:Jsb...@li...>>
Cc: Simon Julie Morley <sim...@go...<mailto:sim...@go...>>
Subject: [Jsbsim-devel] Helicopter

Anyone here ever done one ?

Want to talk about it, share knowledge ?

Simon

_______________________________________________
Jsbsim-devel mailing list
Jsb...@li...<mailto:Jsb...@li...>
https://lists.sourceforge.net/lists/listinfo/jsbsim-devel
_______________________________________________
The JSBSim Flight Dynamics Model project
http://www.JSBSim.org
_______________________________________________

I'm not a C++ coder I work on xml code.

It's not a case of ignoring rotor functionality but more a case of after
10+ years of only working on propellers, (in fact the first time i touched
a turbine was doing the avatar Scorpion gunship) I'm extremely familiar
with how the to create propeller tables and how the  propeller code works.

To answer the next question, without using any equations describe in your
own words the requirements of, and how flapping is implemented in a real
life helicopter and I'll explain how I do it with a prop.

Simon

On Tue, 27 Oct 2020 at 13:50, Sean McLeod <se...@se...> wrote:

> Hi Simon
>
>
>
> Are you adding code to FGPropeller to implement some of the functionality
> that is currently in FGRotor but not in FGPropeller currently?
>
>
>
> Are there some aspects of FGRotor’s functionality that you’re ignoring
> because you don’t think they’re useful for your needs?
>
>
>
> What things did you notice in FGPropeller that FGRotor can’t currently do?
> Could potentially be useful to add them to FGRotor for users of FGRotor.
>
>
>
> What’s quite useful is Thomas references the equations etc. that his code
> is based on, e.g.
>
>
>
> // Flapping angles relative to control axes /SH79/ eqn(32)
>
> void FGRotor::calc_flapping_angles(double theta_0, const FGColumnVector3 &
> pqr_fus_w)
>
>
>
>     <dt>/SH79/</dt><dd>Shaugnessy, J. D., Deaux, Thomas N., and Yenni,
> Kenneth R.,
>
>               "Development and Validation of a Piloted Simulation of a
>
>               Helicopter and External Sling Load",  NASA TP-1285,
> 1979.</dd>
>
>
>
> https://ntrs.nasa.gov/citations/19790005912
>
>
>
> I’m currently using FGotor for the helicopter models I’m working on so I’d
> be interested to know what you see as the pros and cons of using FGRotor
> versus FGPropeller.
>
>
>
> Cheers
>
>
>
> *From:* Simon Julie Morley via Jsbsim-devel <
> jsb...@li...>
> *Sent:* Monday, October 26, 2020 10:09 PM
> *To:* Development issues <Jsb...@li...>
> *Cc:* Simon Julie Morley <sim...@go...>
> *Subject:* [Jsbsim-devel] Fwd: Helicopter
>
>
>
>
>   yeh I have, and there's nothing in it I can't do with a propeller, and
> actually there are things in the propeller code that the rotor can't do....
> so using rotor is a net less...
>
>
>
> Simon
>
>
>
> ---------- Forwarded message ---------
> From: *Sean McLeod* <se...@se...>
> Date: Mon, 26 Oct 2020 at 20:00
> Subject: RE: [Jsbsim-devel] Helicopter
> To: Simon Julie Morley <sim...@go...>
>
>
>
> Hi Simon
>
>
>
> Have you looked at the FGRotor code to see what helicopter specific stuff
> it models that isn’t modeled by FGPropeller?
>
>
>
> Cheers
>
>
>
> *From:* Simon Julie Morley <sim...@go...>
> *Sent:* Monday, October 26, 2020 5:19 PM
> *To:* Sean McLeod <se...@se...>
> *Subject:* Re: [Jsbsim-devel] Helicopter
>
>
>
> Hi Sean,
>
>
>
> I'm not sure about using prop resulting in a lesser quality or that rotor
> offering greater functionality...
>
>
>
> I remain open minded to the possibilities
>
>
>
> Simon.
>
>
>
> On Mon, 26 Oct 2020, 13:08 Sean McLeod, <se...@se...> wrote:
>
> Hi Simon
>
>
>
> I’m sure you can model a helicopter using FGPropeller etc. as a basis, but
> I would imagine it would be a 1st order approximation since there are a
> number of dynamics that FGPropeller doesn’t model compared to FGRotor, so
> FGRotor would more easily allow for a higher fidelity model.
>
>
>
> Cheers
>
>
>
> *From:* Simon Julie Morley via Jsbsim-devel <
> jsb...@li...>
> *Sent:* Sunday, October 25, 2020 11:59 PM
> *To:* Development issues <jsb...@li...>
> *Cc:* Simon Julie Morley <sim...@go...>
> *Subject:* Re: [Jsbsim-devel] Helicopter
>
>
>
> Hi Sean,
>
>
>
> To be honest I wanted to try and see if I could make a helicopter using
> the prop code, because I couldn't see why not.
>
>
>
> On Sun, 25 Oct 2020 at 21:12, Sean McLeod <se...@se...> wrote:
>
> Hi Simon
>
>
>
> I’m just getting started again in terms of looking at JSBSim based
> helicopter models.
>
>
>
> Thomas Kreitler improved the FGRotor model between 2010 – 2012.
>
>
>
>
> https://github.com/JSBSim-Team/jsbsim/blob/4840a621dafe1ce64970990ddaec3e86a1c7e082/src/models/propulsion/FGRotor.cpp
>
>
>
> He also added a fairly detailed helicopter model for the AH1S:
>
>
>
>
> https://github.com/JSBSim-Team/jsbsim/tree/4840a621dafe1ce64970990ddaec3e86a1c7e082/aircraft/ah1s
>
>
>
> In general there are very few JSBSim based helicopter models around when I
> last looked.
>
>
>
> Cheers
>
>
>
> *From:* Bill Galbraith <bil...@gm...>
> *Sent:* Sunday, October 25, 2020 8:08 PM
> *To:* 'Development issues' <jsb...@li...>
> *Subject:* Re: [Jsbsim-devel] Helicopter
>
>
>
> Simon,
>
>
>
> I had devoted some brain cells towards that idea a while ago, but never
> implemented it.
>
>
>
> Imagine a point mass, with a point vertical force located above it. At 50%
> collective, vertical force equals weight. Cyclic tilts that vertical force
> fore/aft, left/right. Displacing the cyclic yields a slight loss (sine of
> angle) loss of lift, requiring slightly more collective.
>
>
>
> The painful part comes when you try to fly it with a joystick. When you
> release the joystick, the cyclic returns back to neutral, the aircraft will
> slow to a hover. You basically need a joystick that has a trim lever, or
> allows you to reestablish the trim point.
>
>
>
> Enough to get your brain cells excited?
>
>
>
> Bill
>
>
>
> *From:* Simon Julie Morley via Jsbsim-devel [
> mailto:jsb...@li...
> <jsb...@li...>]
> *Sent:* Sunday, October 25, 2020 1:41 PM
> *To:* Development issues <Jsb...@li...>
> *Cc:* Simon Julie Morley <sim...@go...>
> *Subject:* [Jsbsim-devel] Helicopter
>
>
>
> Anyone here ever done one ?
>
>
>
> Want to talk about it, share knowledge ?
>
>
>
> Simon
>
>
>
>
>
>
>
> _______________________________________________
> Jsbsim-devel mailing list
> Jsb...@li...
> https://lists.sourceforge.net/lists/listinfo/jsbsim-devel
> _______________________________________________
> The JSBSim Flight Dynamics Model project
> http://www.JSBSim.org
> _______________________________________________
>
> _______________________________________________
> Jsbsim-devel mailing list
> Jsb...@li...
> https://lists.sourceforge.net/lists/listinfo/jsbsim-devel
> _______________________________________________
> The JSBSim Flight Dynamics Model project
> http://www.JSBSim.org
> _______________________________________________
>
>

Come on, it wasn't that hard a question

On Tue, 27 Oct 2020 at 15:54, Simon Julie Morley <
sim...@go...> wrote:

> I'm not a C++ coder I work on xml code.
>
> It's not a case of ignoring rotor functionality but more a case of after
> 10+ years of only working on propellers, (in fact the first time i touched
> a turbine was doing the avatar Scorpion gunship) I'm extremely familiar
> with how the to create propeller tables and how the  propeller code works.
>
> To answer the next question, without using any equations describe in your
> own words the requirements of, and how flapping is implemented in a real
> life helicopter and I'll explain how I do it with a prop.
>
> Simon
>
> On Tue, 27 Oct 2020 at 13:50, Sean McLeod <se...@se...> wrote:
>
>> Hi Simon
>>
>>
>>
>> Are you adding code to FGPropeller to implement some of the functionality
>> that is currently in FGRotor but not in FGPropeller currently?
>>
>>
>>
>> Are there some aspects of FGRotor’s functionality that you’re ignoring
>> because you don’t think they’re useful for your needs?
>>
>>
>>
>> What things did you notice in FGPropeller that FGRotor can’t currently
>> do? Could potentially be useful to add them to FGRotor for users of FGRotor.
>>
>>
>>
>> What’s quite useful is Thomas references the equations etc. that his code
>> is based on, e.g.
>>
>>
>>
>> // Flapping angles relative to control axes /SH79/ eqn(32)
>>
>> void FGRotor::calc_flapping_angles(double theta_0, const FGColumnVector3
>> &pqr_fus_w)
>>
>>
>>
>>     <dt>/SH79/</dt><dd>Shaugnessy, J. D., Deaux, Thomas N., and Yenni,
>> Kenneth R.,
>>
>>               "Development and Validation of a Piloted Simulation of a
>>
>>               Helicopter and External Sling Load",  NASA TP-1285,
>> 1979.</dd>
>>
>>
>>
>> https://ntrs.nasa.gov/citations/19790005912
>>
>>
>>
>> I’m currently using FGotor for the helicopter models I’m working on so
>> I’d be interested to know what you see as the pros and cons of using
>> FGRotor versus FGPropeller.
>>
>>
>>
>> Cheers
>>
>>
>>
>> *From:* Simon Julie Morley via Jsbsim-devel <
>> jsb...@li...>
>> *Sent:* Monday, October 26, 2020 10:09 PM
>> *To:* Development issues <Jsb...@li...>
>> *Cc:* Simon Julie Morley <sim...@go...>
>> *Subject:* [Jsbsim-devel] Fwd: Helicopter
>>
>>
>>
>>
>>   yeh I have, and there's nothing in it I can't do with a propeller, and
>> actually there are things in the propeller code that the rotor can't do....
>> so using rotor is a net less...
>>
>>
>>
>> Simon
>>
>>
>>
>> ---------- Forwarded message ---------
>> From: *Sean McLeod* <se...@se...>
>> Date: Mon, 26 Oct 2020 at 20:00
>> Subject: RE: [Jsbsim-devel] Helicopter
>> To: Simon Julie Morley <sim...@go...>
>>
>>
>>
>> Hi Simon
>>
>>
>>
>> Have you looked at the FGRotor code to see what helicopter specific stuff
>> it models that isn’t modeled by FGPropeller?
>>
>>
>>
>> Cheers
>>
>>
>>
>> *From:* Simon Julie Morley <sim...@go...>
>> *Sent:* Monday, October 26, 2020 5:19 PM
>> *To:* Sean McLeod <se...@se...>
>> *Subject:* Re: [Jsbsim-devel] Helicopter
>>
>>
>>
>> Hi Sean,
>>
>>
>>
>> I'm not sure about using prop resulting in a lesser quality or that rotor
>> offering greater functionality...
>>
>>
>>
>> I remain open minded to the possibilities
>>
>>
>>
>> Simon.
>>
>>
>>
>> On Mon, 26 Oct 2020, 13:08 Sean McLeod, <se...@se...> wrote:
>>
>> Hi Simon
>>
>>
>>
>> I’m sure you can model a helicopter using FGPropeller etc. as a basis,
>> but I would imagine it would be a 1st order approximation since there
>> are a number of dynamics that FGPropeller doesn’t model compared to
>> FGRotor, so FGRotor would more easily allow for a higher fidelity model.
>>
>>
>>
>> Cheers
>>
>>
>>
>> *From:* Simon Julie Morley via Jsbsim-devel <
>> jsb...@li...>
>> *Sent:* Sunday, October 25, 2020 11:59 PM
>> *To:* Development issues <jsb...@li...>
>> *Cc:* Simon Julie Morley <sim...@go...>
>> *Subject:* Re: [Jsbsim-devel] Helicopter
>>
>>
>>
>> Hi Sean,
>>
>>
>>
>> To be honest I wanted to try and see if I could make a helicopter using
>> the prop code, because I couldn't see why not.
>>
>>
>>
>> On Sun, 25 Oct 2020 at 21:12, Sean McLeod <se...@se...> wrote:
>>
>> Hi Simon
>>
>>
>>
>> I’m just getting started again in terms of looking at JSBSim based
>> helicopter models.
>>
>>
>>
>> Thomas Kreitler improved the FGRotor model between 2010 – 2012.
>>
>>
>>
>>
>> https://github.com/JSBSim-Team/jsbsim/blob/4840a621dafe1ce64970990ddaec3e86a1c7e082/src/models/propulsion/FGRotor.cpp
>>
>>
>>
>> He also added a fairly detailed helicopter model for the AH1S:
>>
>>
>>
>>
>> https://github.com/JSBSim-Team/jsbsim/tree/4840a621dafe1ce64970990ddaec3e86a1c7e082/aircraft/ah1s
>>
>>
>>
>> In general there are very few JSBSim based helicopter models around when
>> I last looked.
>>
>>
>>
>> Cheers
>>
>>
>>
>> *From:* Bill Galbraith <bil...@gm...>
>> *Sent:* Sunday, October 25, 2020 8:08 PM
>> *To:* 'Development issues' <jsb...@li...>
>> *Subject:* Re: [Jsbsim-devel] Helicopter
>>
>>
>>
>> Simon,
>>
>>
>>
>> I had devoted some brain cells towards that idea a while ago, but never
>> implemented it.
>>
>>
>>
>> Imagine a point mass, with a point vertical force located above it. At
>> 50% collective, vertical force equals weight. Cyclic tilts that vertical
>> force fore/aft, left/right. Displacing the cyclic yields a slight loss
>> (sine of angle) loss of lift, requiring slightly more collective.
>>
>>
>>
>> The painful part comes when you try to fly it with a joystick. When you
>> release the joystick, the cyclic returns back to neutral, the aircraft will
>> slow to a hover. You basically need a joystick that has a trim lever, or
>> allows you to reestablish the trim point.
>>
>>
>>
>> Enough to get your brain cells excited?
>>
>>
>>
>> Bill
>>
>>
>>
>> *From:* Simon Julie Morley via Jsbsim-devel [
>> mailto:jsb...@li...
>> <jsb...@li...>]
>> *Sent:* Sunday, October 25, 2020 1:41 PM
>> *To:* Development issues <Jsb...@li...>
>> *Cc:* Simon Julie Morley <sim...@go...>
>> *Subject:* [Jsbsim-devel] Helicopter
>>
>>
>>
>> Anyone here ever done one ?
>>
>>
>>
>> Want to talk about it, share knowledge ?
>>
>>
>>
>> Simon
>>
>>
>>
>>
>>
>>
>>
>> _______________________________________________
>> Jsbsim-devel mailing list
>> Jsb...@li...
>> https://lists.sourceforge.net/lists/listinfo/jsbsim-devel
>> _______________________________________________
>> The JSBSim Flight Dynamics Model project
>> http://www.JSBSim.org
>> _______________________________________________
>>
>> _______________________________________________
>> Jsbsim-devel mailing list
>> Jsb...@li...
>> https://lists.sourceforge.net/lists/listinfo/jsbsim-devel
>> _______________________________________________
>> The JSBSim Flight Dynamics Model project
>> http://www.JSBSim.org
>> _______________________________________________
>>
>>

For those that are interested... The flight model patch can be found here

https://github.com/FGMEMBERS-NONGPL/UH-1

On Fri, 30 Oct 2020, 09:39 Simon Julie Morley, <sim...@go...>
wrote:

> Come on, it wasn't that hard a question
>
> On Tue, 27 Oct 2020 at 15:54, Simon Julie Morley <
> sim...@go...> wrote:
>
>> I'm not a C++ coder I work on xml code.
>>
>> It's not a case of ignoring rotor functionality but more a case of after
>> 10+ years of only working on propellers, (in fact the first time i touched
>> a turbine was doing the avatar Scorpion gunship) I'm extremely familiar
>> with how the to create propeller tables and how the  propeller code works.
>>
>> To answer the next question, without using any equations describe in your
>> own words the requirements of, and how flapping is implemented in a real
>> life helicopter and I'll explain how I do it with a prop.
>>
>> Simon
>>
>> On Tue, 27 Oct 2020 at 13:50, Sean McLeod <se...@se...> wrote:
>>
>>> Hi Simon
>>>
>>>
>>>
>>> Are you adding code to FGPropeller to implement some of the
>>> functionality that is currently in FGRotor but not in FGPropeller currently?
>>>
>>>
>>>
>>> Are there some aspects of FGRotor’s functionality that you’re ignoring
>>> because you don’t think they’re useful for your needs?
>>>
>>>
>>>
>>> What things did you notice in FGPropeller that FGRotor can’t currently
>>> do? Could potentially be useful to add them to FGRotor for users of FGRotor.
>>>
>>>
>>>
>>> What’s quite useful is Thomas references the equations etc. that his
>>> code is based on, e.g.
>>>
>>>
>>>
>>> // Flapping angles relative to control axes /SH79/ eqn(32)
>>>
>>> void FGRotor::calc_flapping_angles(double theta_0, const FGColumnVector3
>>> &pqr_fus_w)
>>>
>>>
>>>
>>>     <dt>/SH79/</dt><dd>Shaugnessy, J. D., Deaux, Thomas N., and Yenni,
>>> Kenneth R.,
>>>
>>>               "Development and Validation of a Piloted Simulation of a
>>>
>>>               Helicopter and External Sling Load",  NASA TP-1285,
>>> 1979.</dd>
>>>
>>>
>>>
>>> https://ntrs.nasa.gov/citations/19790005912
>>>
>>>
>>>
>>> I’m currently using FGotor for the helicopter models I’m working on so
>>> I’d be interested to know what you see as the pros and cons of using
>>> FGRotor versus FGPropeller.
>>>
>>>
>>>
>>> Cheers
>>>
>>>
>>>
>>> *From:* Simon Julie Morley via Jsbsim-devel <
>>> jsb...@li...>
>>> *Sent:* Monday, October 26, 2020 10:09 PM
>>> *To:* Development issues <Jsb...@li...>
>>> *Cc:* Simon Julie Morley <sim...@go...>
>>> *Subject:* [Jsbsim-devel] Fwd: Helicopter
>>>
>>>
>>>
>>>
>>>   yeh I have, and there's nothing in it I can't do with a propeller, and
>>> actually there are things in the propeller code that the rotor can't do....
>>> so using rotor is a net less...
>>>
>>>
>>>
>>> Simon
>>>
>>>
>>>
>>> ---------- Forwarded message ---------
>>> From: *Sean McLeod* <se...@se...>
>>> Date: Mon, 26 Oct 2020 at 20:00
>>> Subject: RE: [Jsbsim-devel] Helicopter
>>> To: Simon Julie Morley <sim...@go...>
>>>
>>>
>>>
>>> Hi Simon
>>>
>>>
>>>
>>> Have you looked at the FGRotor code to see what helicopter specific
>>> stuff it models that isn’t modeled by FGPropeller?
>>>
>>>
>>>
>>> Cheers
>>>
>>>
>>>
>>> *From:* Simon Julie Morley <sim...@go...>
>>> *Sent:* Monday, October 26, 2020 5:19 PM
>>> *To:* Sean McLeod <se...@se...>
>>> *Subject:* Re: [Jsbsim-devel] Helicopter
>>>
>>>
>>>
>>> Hi Sean,
>>>
>>>
>>>
>>> I'm not sure about using prop resulting in a lesser quality or that
>>> rotor offering greater functionality...
>>>
>>>
>>>
>>> I remain open minded to the possibilities
>>>
>>>
>>>
>>> Simon.
>>>
>>>
>>>
>>> On Mon, 26 Oct 2020, 13:08 Sean McLeod, <se...@se...> wrote:
>>>
>>> Hi Simon
>>>
>>>
>>>
>>> I’m sure you can model a helicopter using FGPropeller etc. as a basis,
>>> but I would imagine it would be a 1st order approximation since there
>>> are a number of dynamics that FGPropeller doesn’t model compared to
>>> FGRotor, so FGRotor would more easily allow for a higher fidelity model.
>>>
>>>
>>>
>>> Cheers
>>>
>>>
>>>
>>> *From:* Simon Julie Morley via Jsbsim-devel <
>>> jsb...@li...>
>>> *Sent:* Sunday, October 25, 2020 11:59 PM
>>> *To:* Development issues <jsb...@li...>
>>> *Cc:* Simon Julie Morley <sim...@go...>
>>> *Subject:* Re: [Jsbsim-devel] Helicopter
>>>
>>>
>>>
>>> Hi Sean,
>>>
>>>
>>>
>>> To be honest I wanted to try and see if I could make a helicopter using
>>> the prop code, because I couldn't see why not.
>>>
>>>
>>>
>>> On Sun, 25 Oct 2020 at 21:12, Sean McLeod <se...@se...> wrote:
>>>
>>> Hi Simon
>>>
>>>
>>>
>>> I’m just getting started again in terms of looking at JSBSim based
>>> helicopter models.
>>>
>>>
>>>
>>> Thomas Kreitler improved the FGRotor model between 2010 – 2012.
>>>
>>>
>>>
>>>
>>> https://github.com/JSBSim-Team/jsbsim/blob/4840a621dafe1ce64970990ddaec3e86a1c7e082/src/models/propulsion/FGRotor.cpp
>>>
>>>
>>>
>>> He also added a fairly detailed helicopter model for the AH1S:
>>>
>>>
>>>
>>>
>>> https://github.com/JSBSim-Team/jsbsim/tree/4840a621dafe1ce64970990ddaec3e86a1c7e082/aircraft/ah1s
>>>
>>>
>>>
>>> In general there are very few JSBSim based helicopter models around when
>>> I last looked.
>>>
>>>
>>>
>>> Cheers
>>>
>>>
>>>
>>> *From:* Bill Galbraith <bil...@gm...>
>>> *Sent:* Sunday, October 25, 2020 8:08 PM
>>> *To:* 'Development issues' <jsb...@li...>
>>> *Subject:* Re: [Jsbsim-devel] Helicopter
>>>
>>>
>>>
>>> Simon,
>>>
>>>
>>>
>>> I had devoted some brain cells towards that idea a while ago, but never
>>> implemented it.
>>>
>>>
>>>
>>> Imagine a point mass, with a point vertical force located above it. At
>>> 50% collective, vertical force equals weight. Cyclic tilts that vertical
>>> force fore/aft, left/right. Displacing the cyclic yields a slight loss
>>> (sine of angle) loss of lift, requiring slightly more collective.
>>>
>>>
>>>
>>> The painful part comes when you try to fly it with a joystick. When you
>>> release the joystick, the cyclic returns back to neutral, the aircraft will
>>> slow to a hover. You basically need a joystick that has a trim lever, or
>>> allows you to reestablish the trim point.
>>>
>>>
>>>
>>> Enough to get your brain cells excited?
>>>
>>>
>>>
>>> Bill
>>>
>>>
>>>
>>> *From:* Simon Julie Morley via Jsbsim-devel [
>>> mailto:jsb...@li...
>>> <jsb...@li...>]
>>> *Sent:* Sunday, October 25, 2020 1:41 PM
>>> *To:* Development issues <Jsb...@li...>
>>> *Cc:* Simon Julie Morley <sim...@go...>
>>> *Subject:* [Jsbsim-devel] Helicopter
>>>
>>>
>>>
>>> Anyone here ever done one ?
>>>
>>>
>>>
>>> Want to talk about it, share knowledge ?
>>>
>>>
>>>
>>> Simon
>>>
>>>
>>>
>>>
>>>
>>>
>>>
>>> _______________________________________________
>>> Jsbsim-devel mailing list
>>> Jsb...@li...
>>> https://lists.sourceforge.net/lists/listinfo/jsbsim-devel
>>> _______________________________________________
>>> The JSBSim Flight Dynamics Model project
>>> http://www.JSBSim.org
>>> _______________________________________________
>>>
>>> _______________________________________________
>>> Jsbsim-devel mailing list
>>> Jsb...@li...
>>> https://lists.sourceforge.net/lists/listinfo/jsbsim-devel
>>> _______________________________________________
>>> The JSBSim Flight Dynamics Model project
>>> http://www.JSBSim.org
>>> _______________________________________________
>>>
>>>

Thomas,

You might already know or be interested in knowing that Titan are using
your bk117 in their sim

"    <author> Thomas Kreitler </author>
    <email> t.kreitler at web 056 de </email>
    <filecreationdate>2010-10-07</filecreationdate>
    <version>$Revision: 1.5 $</version>
    <description> Models a Bell209/AH1S helicopter. </description>
"
regards

Simon

On Wed, 4 Nov 2020 at 22:01, Simon Julie Morley <
sim...@go...> wrote:

> For those that are interested... The flight model patch can be found here
>
> https://github.com/FGMEMBERS-NONGPL/UH-1
>
> On Fri, 30 Oct 2020, 09:39 Simon Julie Morley, <
> sim...@go...> wrote:
>
>> Come on, it wasn't that hard a question
>>
>> On Tue, 27 Oct 2020 at 15:54, Simon Julie Morley <
>> sim...@go...> wrote:
>>
>>> I'm not a C++ coder I work on xml code.
>>>
>>> It's not a case of ignoring rotor functionality but more a case of after
>>> 10+ years of only working on propellers, (in fact the first time i touched
>>> a turbine was doing the avatar Scorpion gunship) I'm extremely familiar
>>> with how the to create propeller tables and how the  propeller code works.
>>>
>>> To answer the next question, without using any equations describe in
>>> your own words the requirements of, and how flapping is implemented in a
>>> real life helicopter and I'll explain how I do it with a prop.
>>>
>>> Simon
>>>
>>> On Tue, 27 Oct 2020 at 13:50, Sean McLeod <se...@se...> wrote:
>>>
>>>> Hi Simon
>>>>
>>>>
>>>>
>>>> Are you adding code to FGPropeller to implement some of the
>>>> functionality that is currently in FGRotor but not in FGPropeller currently?
>>>>
>>>>
>>>>
>>>> Are there some aspects of FGRotor’s functionality that you’re ignoring
>>>> because you don’t think they’re useful for your needs?
>>>>
>>>>
>>>>
>>>> What things did you notice in FGPropeller that FGRotor can’t currently
>>>> do? Could potentially be useful to add them to FGRotor for users of FGRotor.
>>>>
>>>>
>>>>
>>>> What’s quite useful is Thomas references the equations etc. that his
>>>> code is based on, e.g.
>>>>
>>>>
>>>>
>>>> // Flapping angles relative to control axes /SH79/ eqn(32)
>>>>
>>>> void FGRotor::calc_flapping_angles(double theta_0, const
>>>> FGColumnVector3 &pqr_fus_w)
>>>>
>>>>
>>>>
>>>>     <dt>/SH79/</dt><dd>Shaugnessy, J. D., Deaux, Thomas N., and Yenni,
>>>> Kenneth R.,
>>>>
>>>>               "Development and Validation of a Piloted Simulation of a
>>>>
>>>>               Helicopter and External Sling Load",  NASA TP-1285,
>>>> 1979.</dd>
>>>>
>>>>
>>>>
>>>> https://ntrs.nasa.gov/citations/19790005912
>>>>
>>>>
>>>>
>>>> I’m currently using FGotor for the helicopter models I’m working on so
>>>> I’d be interested to know what you see as the pros and cons of using
>>>> FGRotor versus FGPropeller.
>>>>
>>>>
>>>>
>>>> Cheers
>>>>
>>>>
>>>>
>>>> *From:* Simon Julie Morley via Jsbsim-devel <
>>>> jsb...@li...>
>>>> *Sent:* Monday, October 26, 2020 10:09 PM
>>>> *To:* Development issues <Jsb...@li...>
>>>> *Cc:* Simon Julie Morley <sim...@go...>
>>>> *Subject:* [Jsbsim-devel] Fwd: Helicopter
>>>>
>>>>
>>>>
>>>>
>>>>   yeh I have, and there's nothing in it I can't do with a propeller,
>>>> and actually there are things in the propeller code that the rotor can't
>>>> do.... so using rotor is a net less...
>>>>
>>>>
>>>>
>>>> Simon
>>>>
>>>>
>>>>
>>>> ---------- Forwarded message ---------
>>>> From: *Sean McLeod* <se...@se...>
>>>> Date: Mon, 26 Oct 2020 at 20:00
>>>> Subject: RE: [Jsbsim-devel] Helicopter
>>>> To: Simon Julie Morley <sim...@go...>
>>>>
>>>>
>>>>
>>>> Hi Simon
>>>>
>>>>
>>>>
>>>> Have you looked at the FGRotor code to see what helicopter specific
>>>> stuff it models that isn’t modeled by FGPropeller?
>>>>
>>>>
>>>>
>>>> Cheers
>>>>
>>>>
>>>>
>>>> *From:* Simon Julie Morley <sim...@go...>
>>>> *Sent:* Monday, October 26, 2020 5:19 PM
>>>> *To:* Sean McLeod <se...@se...>
>>>> *Subject:* Re: [Jsbsim-devel] Helicopter
>>>>
>>>>
>>>>
>>>> Hi Sean,
>>>>
>>>>
>>>>
>>>> I'm not sure about using prop resulting in a lesser quality or that
>>>> rotor offering greater functionality...
>>>>
>>>>
>>>>
>>>> I remain open minded to the possibilities
>>>>
>>>>
>>>>
>>>> Simon.
>>>>
>>>>
>>>>
>>>> On Mon, 26 Oct 2020, 13:08 Sean McLeod, <se...@se...> wrote:
>>>>
>>>> Hi Simon
>>>>
>>>>
>>>>
>>>> I’m sure you can model a helicopter using FGPropeller etc. as a basis,
>>>> but I would imagine it would be a 1st order approximation since there
>>>> are a number of dynamics that FGPropeller doesn’t model compared to
>>>> FGRotor, so FGRotor would more easily allow for a higher fidelity model.
>>>>
>>>>
>>>>
>>>> Cheers
>>>>
>>>>
>>>>
>>>> *From:* Simon Julie Morley via Jsbsim-devel <
>>>> jsb...@li...>
>>>> *Sent:* Sunday, October 25, 2020 11:59 PM
>>>> *To:* Development issues <jsb...@li...>
>>>> *Cc:* Simon Julie Morley <sim...@go...>
>>>> *Subject:* Re: [Jsbsim-devel] Helicopter
>>>>
>>>>
>>>>
>>>> Hi Sean,
>>>>
>>>>
>>>>
>>>> To be honest I wanted to try and see if I could make a helicopter using
>>>> the prop code, because I couldn't see why not.
>>>>
>>>>
>>>>
>>>> On Sun, 25 Oct 2020 at 21:12, Sean McLeod <se...@se...> wrote:
>>>>
>>>> Hi Simon
>>>>
>>>>
>>>>
>>>> I’m just getting started again in terms of looking at JSBSim based
>>>> helicopter models.
>>>>
>>>>
>>>>
>>>> Thomas Kreitler improved the FGRotor model between 2010 – 2012.
>>>>
>>>>
>>>>
>>>>
>>>> https://github.com/JSBSim-Team/jsbsim/blob/4840a621dafe1ce64970990ddaec3e86a1c7e082/src/models/propulsion/FGRotor.cpp
>>>>
>>>>
>>>>
>>>> He also added a fairly detailed helicopter model for the AH1S:
>>>>
>>>>
>>>>
>>>>
>>>> https://github.com/JSBSim-Team/jsbsim/tree/4840a621dafe1ce64970990ddaec3e86a1c7e082/aircraft/ah1s
>>>>
>>>>
>>>>
>>>> In general there are very few JSBSim based helicopter models around
>>>> when I last looked.
>>>>
>>>>
>>>>
>>>> Cheers
>>>>
>>>>
>>>>
>>>> *From:* Bill Galbraith <bil...@gm...>
>>>> *Sent:* Sunday, October 25, 2020 8:08 PM
>>>> *To:* 'Development issues' <jsb...@li...>
>>>> *Subject:* Re: [Jsbsim-devel] Helicopter
>>>>
>>>>
>>>>
>>>> Simon,
>>>>
>>>>
>>>>
>>>> I had devoted some brain cells towards that idea a while ago, but never
>>>> implemented it.
>>>>
>>>>
>>>>
>>>> Imagine a point mass, with a point vertical force located above it. At
>>>> 50% collective, vertical force equals weight. Cyclic tilts that vertical
>>>> force fore/aft, left/right. Displacing the cyclic yields a slight loss
>>>> (sine of angle) loss of lift, requiring slightly more collective.
>>>>
>>>>
>>>>
>>>> The painful part comes when you try to fly it with a joystick. When you
>>>> release the joystick, the cyclic returns back to neutral, the aircraft will
>>>> slow to a hover. You basically need a joystick that has a trim lever, or
>>>> allows you to reestablish the trim point.
>>>>
>>>>
>>>>
>>>> Enough to get your brain cells excited?
>>>>
>>>>
>>>>
>>>> Bill
>>>>
>>>>
>>>>
>>>> *From:* Simon Julie Morley via Jsbsim-devel [
>>>> mailto:jsb...@li...
>>>> <jsb...@li...>]
>>>> *Sent:* Sunday, October 25, 2020 1:41 PM
>>>> *To:* Development issues <Jsb...@li...>
>>>> *Cc:* Simon Julie Morley <sim...@go...>
>>>> *Subject:* [Jsbsim-devel] Helicopter
>>>>
>>>>
>>>>
>>>> Anyone here ever done one ?
>>>>
>>>>
>>>>
>>>> Want to talk about it, share knowledge ?
>>>>
>>>>
>>>>
>>>> Simon
>>>>
>>>>
>>>>
>>>>
>>>>
>>>>
>>>>
>>>> _______________________________________________
>>>> Jsbsim-devel mailing list
>>>> Jsb...@li...
>>>> https://lists.sourceforge.net/lists/listinfo/jsbsim-devel
>>>> _______________________________________________
>>>> The JSBSim Flight Dynamics Model project
>>>> http://www.JSBSim.org
>>>> _______________________________________________
>>>>
>>>> _______________________________________________
>>>> Jsbsim-devel mailing list
>>>> Jsb...@li...
>>>> https://lists.sourceforge.net/lists/listinfo/jsbsim-devel
>>>> _______________________________________________
>>>> The JSBSim Flight Dynamics Model project
>>>> http://www.JSBSim.org
>>>> _______________________________________________
>>>>
>>>>

Thread: [Jsbsim-devel] Helicopter

An open source flight dynamics & control software library in C++

jsbsim-devel