savi-users — for any users of the SaVi satellite simulation software

[savi-users] SaVi student project was Re: Urgent Help Request

[Lloyd W <llo...@ya...>]

To bring this old query below to a happy conclusion, Ahmad & Ahmad & co.'s project results , using SaVi, are now on Github.

https://github.com/AhmadAtwi10/Satellite-Constellation-

It seems that they found SaVi useful, and did okay.

Lloyd Wood 
SaVi http://savi.sf.net/

> On 31 Jan 2024, at 06:28, Ahmad Harakeh via savi-users <sav...@li...> wrote:
> 
> Hello,
> 
> Hope this email finds you well,
> 
> I have a joint project about LEO Satellite routing optimization and I am working on SaVi simulator and we have to calculate some metrics such as the RTT and link utilization for transmitted packets between two LEO satellites from different cities like Paris and San Fransisco, but till now I didn't realize all the feature that help doing these metrics even after downloading the last release SaVi 1.6.0 (April 2023).
> So kindly if you may please help and guide me to install the latest release with all packages and features installed and how to calculate such metrics.
> 
> I will be grateful and much appreciated for your help and consideration.

[savi-users] Getting Mini-SaVi to run: SaVi with network traffic

[<llo...@us...>]

SaVi is now also a constellation network simulator!

Putting SaVi together with mini-net to do network simulation of an intersatellite mesh was described in:

Zhu Tang et al., Mini-Savi: Realistic Satellite Network Simulation Platform Based on Open-Source Tools, Proceedings of the Fourth International Conference on Frontiers of Computers and Communication Engineering (FCCE), Xiamen, China, January 2023.

https://www.researchgate.net/publication/373789005_Mini-Savi_Realistic_Satellite_Network_Simulation_Platform_Based_on_Open-Source_Tools 
http://dx.doi.org/10.1109/FCCE58525.2023.00013

the code used (a customised SaVi 1.5.1 talking to network simulation) was put on github a year later, in March 2024, and, a year later again in April 2025, I've finally just noticed that that public code exists.

So far, I've been able to build and run Mini-Savi. There are a couple of modified Iridium scripts that hand over topology from SaVi to a python mini-net that runs frrr (isisd and zebra routing code).

My comprehensive, detailed, and easy-to-follow installation instructions are at:

https://github.com/zhutang/mini-savi/issues/1 

I hope this proves to be interesting and useful.

Noted on SaVi's papers page, along with the still-private intersatellite link modifications:
http://savi.sf.net/papers/

Recent SaVi betas have added some map lines and Tcl 9.0 compatibility
http://savi.sf.net/beta/

best

Lloyd Wood 
SaVi satellite constellation visualization 
http://savi.sf.net/ 

[savi-users] New SaVi development drop - Tcl/Tk 9.0 and Mac OS X compatibility

[<llo...@us...>]

http://savi.sf.net/beta

I've just put support for Tcl/Tk 9.0 and better support for Mac OS X
into SaVi development. This adds to the new simulation scripts, Mars
simulation, and coverage map options that are already in development. 

(The Tk supplied with current Mac OS X is broken, so you do need to
 install your own version of Tcl/Tk before building SaVi.
 Menus are not currently in the menubar, but are at the top of
 windows just like other platforms; that needs a little more thought.
 But at least they're not blue!)

And a belated happy new year to you all.

Lloyd Wood
llo...@us...

[savi-users] Mars, baby!

[<llo...@us...>]

https://savi.sourceforge.io/beta/

The latest development drop of SaVi allows you to select Mars in the Simulation constants. If you turn off the Earth map and set the blue decay to red, you can almost imagine you're there... drawing appropriate landmaps is a future problem.

The Clarke three-satellite stationary script works at the right height, through drift (which is different to Earth's) is not simulated that accurately.

A nice article on how drifting happens at Mars stationary:
https://www.planetary.org/articles/stationkeeping-in-mars-orbit

This is very much an experimental feature.

Suggestions on other bodies worth adding welcomed.

Lloyd Wood
llo...@us...

[savi-users] new SaVi beta drop

[<llo...@us...>]

https://savi.sourceforge.io/beta/


The latest beta drop of SaVi includes support for drawing the equator and tropics of Cancer and Capricorn in the Coverage View.


This turned out to be rather more effort than I'd expected for just drawing a couple of lines...


Lloyd Wood
llo...@us...

[savi-users] New SaVi development drop

[<llo...@us...>]

https://savi.sourceforge.io/beta/

the 27 August snapshot adds simulations of:

Tianqin, a gravity-wave sensor constellation.

Reflect Orbital, a sun-synchronous plane extending day into night.

Nothing fancy, but different use cases than the rest of the constellations that are simulated.

best,

Lloyd Wood
llo...@us...

Re: [savi-users] Urgent Help Request

[<llo...@ya...>]

And my mail client and the mailing list mangled the "smart" url link in my last post... sigh. So, repeating it for posterity.

https://lloydwood.users.sourceforge.net/Personal/L.Wood/ns/packet-delay-script/ 
that shows path delay measurements - double those delays to get RTT. And that's the script I used with ns-2 tracefiles, following ch. 17 of the ns-2 manual.
there's also some confusion over what is in SaVi 1.6 - Lin Han's group has added to SaVi, and shown their modifications in a number of papers and presentations. However, they have not made their code available to me or publically, so those features are not in SaVi 1.6.
https://savi.sourceforge.io/papers/index.html#isl 
Lloyd Wood http://savi.sf.net/ 

On Sat, 3 Feb 2024 at 1:08 AM lloyd.wood--- via savi-users <sav...@li...> wrote:

This reply didn't appear to make it to the list archive, so forwarding a copy.

Ahmad,
you need to read my research papers, where I did those calculations with ns-2.
This list will get you started.


My PhD thesis basically demonstrates what you are asked to do.
regards
Lloyd Wood llo...@ya...

On 31 Jan 2024, at 06:28, Ahmad Harakeh via savi-users <sav...@li...> wrote:

I have a joint project about LEO Satellite routing optimization and I am working on SaVi simulator and we have to calculate some metrics such as the RTT and link utilization for transmitted packets between two LEO satellites from different cities like Paris and San Fransisco, but till now I didn't realize all the feature that help doing these metrics even after downloading the last release SaVi 1.6.0 (April 2023).

Re: [savi-users] Urgent Help Request

[<llo...@ya...>]

This reply didn't appear to make it to the list archive, so forwarding a copy.

Ahmad,
you need to read my research papers, where I did those calculations with ns-2.
This list will get you started.
| 
| Lloyd Wood - introducing ns - packet delay awk scriptusers.sourceforge.net |  |

 |


My PhD thesis basically demonstrates what you are asked to do.
regards
Lloyd Wood llo...@ya...

On 31 Jan 2024, at 06:28, Ahmad Harakeh via savi-users <sav...@li...> wrote:



Hello,

Hope this email finds you well,

I have a joint project about LEO Satellite routing optimization and I am working on SaVi simulator and we have to calculate some metrics such as the RTT and link utilization for transmitted packets between two LEO satellites from different cities like Paris and San Fransisco, but till now I didn't realize all the feature that help doing these metrics even after downloading the last release SaVi 1.6.0 (April 2023).
So kindly if you may please help and guide me to install the latest release with all packages and features installed and how to calculate such metrics.

[savi-users] Urgent Help Request

[Ahmad H. <ahm...@gm...>]

Hello,

Hope this email finds you well,

I have a joint project about LEO Satellite routing optimization and I am working on SaVi simulator and we have to calculate some metrics such as the RTT and link utilization for transmitted packets between two LEO satellites from different cities like Paris and San Fransisco, but till now I didn't realize all the feature that help doing these metrics even after downloading the last release SaVi 1.6.0 (April 2023).
So kindly if you may please help and guide me to install the latest release with all packages and features installed and how to calculate such metrics.

I will be grateful and much appreciated for your help and consideration.

Best Regards,
Ahmad Al Harakeh

[savi-users] SaVi 1.6.0 released

[<llo...@us...>]

SaVi is software for simulation and visualization of satellite orbits, especially
satellite constellations such as O3b, Starlink and Project Kuiper.

The SaVi 1.6.0 release (30 April 2023) integrates with v1.2 of the satellite plot
scripts for better presentation of SaVi coverage maps, adds a reworked hierarchical
menu structure with submenus, adds simulations of Audacy, Karousel, Project Kuiper,
Laser Light/HALO, RADARSAT, Starlink, Telesat, Theia and Viasat LEO constellations,
adds simulations of Singh's geosynchronous 4-satellite constellations as described
in Nature Communications, increases maximum number of coverage colors to 29 for
megaconstellations with a direct popup menu, adds menu options for coverage map size,
adds -small-map and -all-maps options, associates fisheye, sunlight and geostationary
satellite behaviour with simulation constants, and suppports wider downloading of
TLEs using lynx
Enjoy!
Lloyd Woodlhttp://savi.sf.net/

[savi-users] SaVi and Geomview showing intersatellite links

[<llo...@us...>]

I stumbled across a video suggesting a variant of SaVi has been modified to simulate intersatellite links -- functionality which doesn't yet exist in mainstream SaVi releases.


https://www.youtube.com/watch?v=M49yyJ0o5YU


This seems related to some work presented to the Internet Engineering Task Force at IETF 112 in November 2021.


https://datatracker.ietf.org/meeting/112/materials/slides-112-rtgwg-3-satelite-semantic-addressing-00


Related internet drafts:

https://datatracker.ietf.org/doc/draft-lhan-problems-requirements-satellite-net/

https://datatracker.ietf.org/doc/draft-lhan-satellite-semantic-addressing/

https://datatracker.ietf.org/doc/draft-lhan-satellite-instructive-routing/



This intersatellite link functionality would be a great addition to SaVi's capabilities, and could be combined with the modifications I've been slowly making (rendering, resizing, submenus...) to improve SaVi for a new release.

http://savi.sf.net/beta/


But, other than the existence of this video as proof of existence, I know nothing about the development of this SaVi variant. Information welcomed...


Lloyd Wood

llo...@us...


SaVi satellite constellation visualization http://savi.sf.net/

[savi-users] SaVi 1,.5.1a released

[<llo...@ya...>]

Happy New Year

SaVi 1.5.1a is just a quick repackage to add a gcc switch
so that SaVi compiles and links as before on gcc 10 and 11.

If you already have SaVi working, you don't need this.

New features continue to be added slowly in beta at
http://savi.sf.net/beta

Lloyd Wood
http://savi.sf.net/

[savi-users] new SaVi development drop

[<llo...@us...>]

http://savi.sf.net/beta

there's a new development drop of SaVi,
primarily to work around the demands
of the gcc 10 and 11 compilers so that
SaVi still compiles easily.

Other changes are listed in that webpage.

best to you in these uncertain times,

Lloyd Wood
http://savi.sf.net/

Re: [savi-users] geomview usage

[<llo...@us...>]

Jeff,

- there isn't a chase-cam feature in SaVi. It might be possible to program one
  by looking at the Geomview manual and how it sets cameras and viewports, but
  that strikes me as quite an involved piece of work, much matrix math etc.

- the Earth sphere rotation rate is set in Simulation Constants (the Edit menu in
  satellites list). Setting it to zero to keep it still in Geomview is a quick hack
  with side-effects -- e.g. geostationary satellites will now clearly precess eastward
  around the Earth, though it's less notable for LEO-only stuff. That's how the
  animation on
  http://www.geom.uiuc.edu/~worfolk/SaVi/simulation.html
  was created.
  Having a camera rotate around and with the Earth at the same angular velocity
  (or sit behind a hidden geo satellite) would be possible, but a lot of work, just
  like the first point above. 

- the fisheye supports a single location, which is shown in purple in the coverage
  window (select 'Plot location on map') If that coverage is texturemapped to Geomview
  you see the purple cross in Geomview. The fisheye code may be amenable to being
  wrapped into an object to spawn multiple fisheye views and crosses. It's in the
  BUGS wishlist.

  The SaVi beta has a much wider range of selectable fisheye locations, btw.

Lloyd Wood
http://savi.sf.net/






On Tuesday, 15 December 2020, 11:32:50 GMT+11, Jeff Rogers <dv...@di...> wrote: 





Hi all,

Thanks for the great tool.  A few questions, mostly with geomview:

- is there a way to have a "chase-cam" in geom view, i.e., a way for the 
camera to keep one satellite centered while the world rotates beneath it?

- is there a way in geomview to keep the central body (the earth) steady 
and rotate the orbits around it?

- I can adjust fisheye view location list in tcl/fisheye.tcl ; is there 
a way to have multiple ground locations shown at a time? And can ground 
locations be shown in geomview?


Cheers!

-J

[savi-users] geomview usage

[Jeff R. <dv...@di...>]

Hi all,

Thanks for the great tool.  A few questions, mostly with geomview:

- is there a way to have a "chase-cam" in geom view, i.e., a way for the 
camera to keep one satellite centered while the world rotates beneath it?

- is there a way in geomview to keep the central body (the earth) steady 
and rotate the orbits around it?

- I can adjust fisheye view location list in tcl/fisheye.tcl ; is there 
a way to have multiple ground locations shown at a time? And can ground 
locations be shown in geomview?


Cheers!

-J

Re: [savi-users] New SaVi beta snapshot

[<llo...@ya...>]

Well, 'some other developments' was an understatement, and it's not just
ViaSat's system that has changed. There's a good summary of filings:


https://www.linkedin.com/pulse/new-fcc-processing-round-prompts-license-requests-frhr-von-der-ropp/? 



New FCC processing round prompts license requests for 81,195 NGSO satellites


So a number of scripts are no longer up to date with where filings are at.
Telesat's is likely the most easily tweakable.


***


Given that some FCC deadlines are due shortly, there may
be some other developments with other competitors soon.


Lloyd Wood 
http://savi.sf.net/

[savi-users] New SaVi beta snapshot

[<llo...@ya...>]

https://savi.sourceforge.io/beta/


A new beta of SaVi is available. This one adds a simulation
of ViaSat's modified MEO filing, where they went from MEO
to LEO and from 20 satellites to 288 satellites - a rosette,
so not the same as the Boeing 288-satellite Teledesic design.


There is some commentary on this on a ViaSat earning call
today:
https://www.fool.com/earnings/call-transcripts/2020/05/26/viasat-inc-vsat-q4-2020-earnings-call-transcript.aspx


Given that some FCC deadlines are due shortly, there may
be some other developments with other competitors soon.



Lloyd Wood 
http://savi.sf.net/

[savi-users] New SaVi beta snapshot

[<llo...@ya...>]

https://savi.sourceforge.io/beta/


A new beta of SaVi is available. This one tidied up the submenus. 


Surprisingly, I'm not getting as much done on SaVi during lockdown 
as I had hoped. Such are the vagaries of life.



Lloyd Wood 
http://savi.sf.net/

[savi-users] Latest SaVi beta

[<llo...@ya...>]

https://savi.sourceforge.io/beta/


savi-dev-2020-02-02


The latest SaVi beta includes a first attempt at simulating
the 'efficient' four-satellite Singh constellations published
in this month's Nature Communications. Rather hard to tell
if I have the simulations correct based on the figures that
were published in that paper... they're down the Constellations
menu in the 'Other' section.


I'm thinking about the eventual release of SaVi 1.6.0.
Still to do for that is supporting satellites of multiple
colours, which is needed for telling the difference between
overlapping orbital shells of megaconstellations. And
simulating all the shells of Starlink, which would be
subject to change at any point. And doing some tidyup
to maps and to the satellite plot scripts.


Any other suggestions would be welcome.



Lloyd Wood
http://savi.sf.net/

[savi-users] new SaVi beta tarball release

[<llo...@ya...>]

http://savi.sf.net/beta

A new SaVi development beta release is out.

This allows resizing the coverage map at whim,without that annoying 'what size do you want?'dialog.


Feedback is welcome.


Lloyd Wood 
http://savi.sf.net/

  

[savi-users] new SaVI beta tarball release

[<llo...@ya...>]

http://savi.sf.net/beta

A new SaVi development beta release is out.

This includes a simulation of the RADARSAT constellation,and adds a -verbose flag to restore the OOGL comments that areno longer sent to Geomview as unnecessary - useful fordebugging geomview interaction, with 
./savi -fake-geomview > oogl.log

(I'm debugging Geomview because adding colour choices toindividual satellites turns out to require some reworkingof how Geomview defines each satellite...)


Lloyd Wood 
http://savi.sf.net/

[savi-users] Latest SaVi beta - Audacy, Laser Light, Theia

[<llo...@ya...>]

https://savi.sourceforge.io/beta/hh


this latest 22 Sep SaVi tarball adds simulation scripts
for the Audacy, Laser Light (HALO) and Theia proposals.


Further suggestions for things to simulate,
likely based on descriptions in FCC filings,
appreciated.


Lloyd Wood

http://savi.sf.net/

[savi-users] New SaVi beta - updates Starlink

[<llo...@ya...>]

https://savi.sourceforge.io/beta/


I updated the Starlink simuulation to attempt to match their latest filing.

I don't know what they're doing, but then, it seems, neither do they.



Feedback is welcome.


Lloyd Wood

http://savi.sf.net/

[savi-users] New SaVi beta - adds Telesat simulation

[<llo...@ya...>]

https://savi.sourceforge.io/beta/
A new SaVi beta drop is available. Do give it a try.Feedback is welcome.

This adds a Telesat simulation. Their geometry doesnot seem well optimised, but is as close to thepatent application description as I think I can get it.
https://spacenews.com/spacex-says-more-starlink-orbits-will-speed-service-reduce-launch-needs/
SpaceX have recently filed with the FCC to changetheir constellation geometry - again - but I haven'tyet found that paperwork to modify the Starlink
simulation. "Why bother, it will only change again"is my thought...
best

Lloyd Woodhttp://savi.sf.net/

Re: [savi-users] An elliptical simulation puzzle - Karousel

[<llo...@ya...>]

http://savi.sf.net/beta
Another SaVi beta snapshot is now available, with a Karouselsimulation that matches their FCC filing and that looks right.

Thanks to Donald Kennedy for the needed hint.

Lloyd Wood 
http://savi.sf.net