Bullet Vehicle implementation problem

RJNelson68
Posts: 73
Joined: Tue Oct 06, 2009 3:19 pm

Bullet Vehicle implementation problem

Post by RJNelson68 »

Hi I am working on an implementation of Bullet into the Torque Game Engine Advanced version 1.81. Primarily what I am working on is vehicles but I am seeing a few problems that do not seem to make sense to me. The problems I am seeing is that the suspension is not extending or holding the chassis up from the terrain. Additionally, wheels set to steer rapidly spin back and forth until provided some input. I have already managed to export the variables from the wheelInfo and rayInfo that show it is indeed detecting the terrain and should be doing something, but it is not.

I hosted a couple of videos on Vimeo to show what I am seeing. I hope someone can give me a couple of pointers on how to approach this or were the problem might be. Thank you for any help you can give me.

http://www.vimeo.com/6992045

http://www.vimeo.com/6992136
RJNelson68
Posts: 73
Joined: Tue Oct 06, 2009 3:19 pm

Re: Bullet Vehicle implementation problem

Post by RJNelson68 »

Disregard the rotating wheels issue, it turns out it was an implementation problem between TGEA and Bullet. I solved that one. However, I am still not sure what is causing the rigid suspension.
kester
Posts: 27
Joined: Mon Dec 01, 2008 5:08 am

Re: Bullet Vehicle implementation problem

Post by kester »

What have you set the suspension parameters m_suspensionRestLength1, m_maxSuspensionTravelCm, m_suspensionStiffness, m_wheelsDampingCompression, m_wheelsDampingRelaxation, and the chassis mass to?

Start by increasing the first three - this should provide more force to keep the chassis off the ground.
RJNelson68
Posts: 73
Joined: Tue Oct 06, 2009 3:19 pm

Re: Bullet Vehicle implementation problem

Post by RJNelson68 »

Thanks Kester it turned out I didn't notice the transition between centimeters for one portion and meters in another for adding the settings. The suspension is fine now, but I am seeing some other things I didn't mention before because I thought it was just the suspension causing the problems. That is my vehicle tends to slip around a lot and cannot be driven even though I know I have the same friction settings as the demo. Additionally, I have noticed the suspension does not elongate when the vehicle wheels are not making surface contact. The suspension just remains at its resting point. I am having another problem with the steering settings as well, but I beleive that might be my implementation causing that. Here is a quick video showing what I mean.

http://www.vimeo.com/7013286
rrck
Posts: 26
Joined: Mon Sep 21, 2009 7:30 am

Re: Bullet Vehicle implementation problem

Post by rrck »

Just a guess. Do your world axis are similar to default vehicle axis, Y possitive is Up?
rrck
Posts: 26
Joined: Mon Sep 21, 2009 7:30 am

Re: Bullet Vehicle implementation problem

Post by rrck »

Sorry I was wrong. By default in vehicle X - is right, Y is forward an Z is up.
RJNelson68
Posts: 73
Joined: Tue Oct 06, 2009 3:19 pm

Re: Bullet Vehicle implementation problem

Post by RJNelson68 »

Yes that is correct. I used the settings from the demo to cover that difference.Even tried switching them to the other to see if it would make a difference. It did, but not a good one.
RJNelson68
Posts: 73
Joined: Tue Oct 06, 2009 3:19 pm

Re: Bullet Vehicle implementation problem

Post by RJNelson68 »

I found my mistake, I was changing directions for the wheels on each side.