Bullet CCD (Continuous Collision Detection) used in Motion

[dalibor]

Hi everybody,

I have few questions about using of Bullet Physics Engine in Motion Planning. So I hope that somebody has already used it in this way and know more than I do.

1.) How to perform CCD (Continuous Collision Detection) for moving object (btRigidBody) -> I just need to get the answer if the movement of the object is Continuously Collision Free along given path (trajectory) + get some Report (is/isn’t collision free, nearest obstacle along the path, …) as a result. After some reading I think that this can’t be accomplished just by using btCollisionWorld, so there must be used btDiscreteDynamicsWorld (I’ve noticed of btContinuousDynamicsWorld, but it seems not to be completed yet). But it would be nicer if btCollisionWorld would be sufficient.

2.) How perform CCD (Continuous Collision Detection) for moving robotic arm (some device with joints, constraints) -> Finally I will need to check if the robotic arm’s movement between two configurations (states) is Continuously Collision Free. This robotic arm has articulated and translation joints. I understand that if I want to simulate some device I need to use btContinuousDynamicsWorld and Constraints, but I don’t know how to get the answer of Collision check in the shortest time possible instead of running real-time simulation.

3.) How to set my custom movement interpolation method (steering method) for my device (robotic arm) -> I need to have the Continuous Collision Detection performed along the specific trajectory, which could be described by my custom interpolation between two configurations’ points.

I appreciate any help or good hint. And if anybody knows something more complex then Bullet User Manual, please write it here. I would like to learn more (learning from code is sometimes too slow)

Dalibor

[dalibor]

I need to do some decision tomorrow based on knowledge if Bullet can be used as Continuous Collision Checker for Motion Planning. So I really appreciate any hint or opinion.

Can be Bullet Engine used as Continuous Collision Checker for Motion Planning??

If I simplify the question, I need to know the answer at first question above:

1.) How to perform CCD (Continuous Collision Detection) for moving object (btRigidBody) -> I just need to get the answer if the movement of the object is Continuously Collision Free along given path (trajectory) + get some Report (is/isn’t collision free, nearest obstacle along the path, …) as a result. After some reading I think that this can’t be accomplished just by using btCollisionWorld, so there must be used btDiscreteDynamicsWorld (I’ve noticed of btContinuousDynamicsWorld, but it seems not to be completed yet). But it would be nicer if btCollisionWorld would be sufficient.

Any information welcomes,

Dalibor