PxD6Joint Drive Force

Gaming and Visualization Technologies APIs Physics Modeling (closed)
1

I have a simple drive on a pxD6Joint. I am using this as a revolute joint with the twist degree of freedom. And I want to know the force applied by the drive. How do I get that value? Lets say, that for actor0, actor1, constraints frames all have the same orientation but different location with the twist along the x axis. I tried doing a joint->getConstraint()->getForce(force, torque). But that does not appear to include the force generated by the drive. So lets say, I project the torque onto the actor1’s xaxis, the value is always zero. But the drive is clearly exerting a non-zero torque as my mechanism is moving as expected.

Is there any way I can extract this piece of information?

2

Hi

The problem appears to be that only the joint forces for locked axes are reported. Any limits or drives do not report the applied force. I haven’t been able to establish yet what the reason is for this.

If you search the codebase for the code that sets the following flag:

DY_SC_FLAG_OUTPUT_FORCE

you should see that this depends on Px1DConstraintFlag::eOUTPUT_FORCE.

You should be able to get the forces reported for all constraints by ensuring that either DY_SC_FLAG_OUTPUT_FORCE is raised on the flags in the constraint rows or that Px1DConstraintFlag::eOUTPUT_FORCE is raised for all rows by the joint shaders.

Please let me know if this resolves your issue.