Re: simuv2 bug update

Christos Dimitrakakis wrote:
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> |     // Wheel susp.x is not the wheel movement, look at SimSuspCheckIn,
> | it becomes there scaled with
> |     // susp->spring.bellcrank, so we invert this here.
> |     //tdble prexwheel = wheel->susp.x / wheel->susp.spring.bellcrank;
> |
> |     // unreliable value tdble new_susp_x= prexwheel - wheel->rel_vel *
> | SimDeltaTime;
> |
> |
>
>
> Why are you commenting this out? This is not an 'unreliable value'. This
> is used to let the wheel move properly - otherwise the wheel's mass is
> not taken into account.
>
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The code i have presented is not a real fix, but a work-around for the 
problems i was having with the new simuv2. I have tested with this
code. Race results seem to be identical and i can't detect any 
difference in the way the cars drive when i drive the cars. The only
detectable difference between the original code and my "fixed" code is 
that the problem i was having with levitating cars is resolved. As I 
stated in an earlier post,  i  would like to have a real solution to 
this problem that doesn't degrade the accuracy of the simulation.

I think it would be  useful  to  reproduce  the  original  problem.  Try
throwing together a car with the xml file i provided in my first post.
(I can send you the entire car if you want.) Now start a race with the 
car and hit pause right away. You should see the car positioned slightly 
above the track. Look at the of value of new_susp_x in the debugger. I'm 
betting you will see that the value is way off. Now turn
pause off and wait for the race state to change to race. You should see 
the car drop down on the track. Look at the value of new_susp_x. Now the 
value should be correct.

I would like to provide you with a real fix for this problem. Although i 
am a software engineer by profession, i have no experience with physics 
simulations , so i am clueless when i look at physics engine code.

If there is anything you can think of that i can do to help resolve the
problem, i will be happy to help.

Brian

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