Exploding Robot

[zweifel]

Hi guys,

From time to time, my robot explodes or seems to roll unrealistically fast. The joints are in Torque/force mode with Max force set to 100. I tested with both bullet and ode, ode seems more drastic.

This post is related to exploding physics:
viewtopic.php?f=9&t=2365

So should I try setting the hybrid operation? Or this is only true for IK modes?

Have not tried decreasing the max torque/force of the joints help either. Does it help?

[coppelia]

Hello,

can you post your scene? The explosion can have many different reasons.

Cheers

[zweifel]

I small video showing the problem, not sure if this answers your question.
If you want I can send you the scene.

https://www.youtube.com/watch?v=LYK2TWHI5Aw

[coppelia]

Yes, the best would be to post the scene. You modified the robot. What exactly did you modify?
A robot, specially a walking robot, can be difficult to correctly set-up, there are many values that need to be adjusted and sometimes tweaked depending on the physics engine.

Cheers

[zweifel]

All joints were set to torque/force mode and control loop was disabled.

original:

modified:



I could not resize the image using the forum bbcode, so below is the complete figure.
original:
http://oi57.tinypic.com/anj681.jpg
modified:
http://oi57.tinypic.com/ev8f1x.jpg

The scene file with the modified robot is here:
https://drive.google.com/file/d/0B6gzYl ... sp=sharing

[coppelia]

When I run your scene, nothing happens. It seems that there is no controller. How do you move the robot?
But other than that, it is stable.

Cheers

[zweifel]

I am using an external controller.
The movements will be optimized from scratch (evolved by a genetic algorithm).
However, the physics needs to be realistic enough for it to discover realistic behaviors. I tried a different robot and it seems that no explosion ocurred.
I will try decreasing the max torque and report the results.