Re: [simspark-devel] Fwd:[Sserver-three-d] Error with FRP in server 0.5.7

[Hedayat V. <hed...@ai...>]

Hi
Yes, some times (for example when an agent is initialized and before 
doing anything!) there are 3 contact points with zero force! I've added 
checking for zero force in FRP.

About the agent cycle, would you please check it again? It might be 
related to the rounding error mentioned by Yuan. I've added the same fix 
for SimControlThread.

Finally, thanks a lot for the new Nao robot.

Good luck,
Hedayat

/*"Feng Xue" <hen...@ma...>*/ wrote on 03/29/2008 03:34:39 PM:
> Hi all,
>
>      The same problem happens on me too. Maybe it is a "divide 0" problem, I
> guesss.
>
>      By the way, when using multi-thread, the agent cycle is 0.04s. 
>      And I found another ode error. Yuan said it is because that if one of the
> thread trys to call ode function when another thread is doing the physics update,
> ode will fail. Typically, it happens when both of the beam command and joint speed
> command are valid in a cycle.  
>
>   
>> From: C B <kam...@ya...>
>> Reply-To: 
>> To: sse...@li...
>> Subject: [Sserver-three-d] Error with FRP in server 0.5.7
>> Date:Sat, 29 Mar 2008 05:37:12 -0500 (CDT)
>>
>>
>> Hello,
>> I am testing our agent in the new server 0.5.7 and
>> sometimes I get a wrong message in the FRP, like:
>>
>> (FRP(n lf)(c nan nan nan)(f 0.00 0.00 0.00))
>>
>> I was not receiving this message in 0.5.6.
>> Previous messages to that message are valid messages.
>>
>> Also, it seems like there is some kind of "noise"
>> in FRP, for example I am receiving this for some
>> sequential simulation steps:
>>
>> (FRP(n rf)(c -0.08 -0.10 -0.05)(f 0.28 0.42 12.27))
>> (FRP(n lf)(c 0.08 -0.10 -0.05)(f -0.28 0.41 12.27))
>>
>> (FRP(n rf)(c 0.08 0.10 -0.05)(f -0.30 -0.41 12.20))
>> (FRP(n lf)(c -0.08 0.10 -0.05)(f 0.29 -0.42 12.19))
>>
>> (FRP(n rf)(c -0.08 -0.10 -0.05)(f 0.28 0.42 12.28))
>> (FRP(n lf)(c 0.08 -0.10 -0.05)(f -0.26 0.42 12.35))
>>
>> As you can see, the sign of some numbers varies from
>> message to message, both on the point and the force.
>>
>> Best regards,
>> Carlos Bustamante
>> Borregos3D
>>     
>