Collision check of a 6-DOF robotic arm

Question

Initially we started with 3-DOF. We checked collisions in the c-space and it worked well. With 6-DOF we're having problems. Any ideas about how to check collisions for a 6-DOF robotic arm?

--Edit I'm going to clarify my needs. I have a algorithm based on a hybrid architecture (PRM + Q learning) that plan trajectories. As some of you now, when building the roadmap using a PRM algorithm, you need to sample configurations (series of 6 angles for a 6R 6DOF robot in my case as we are working in the configuration space). You have to check if these configurations lead to a collision or not. If not you add them to the roadmap. My problem is with the part where i need to check if a configuration leads to a collision. At first, when we were testing for a 3R 3DOF robot, we had a brute-force method that worked pretty well but i'm not going into the details here unless some of you are interested. This method didn't work for a 6R robot for many reasons. What i need is a check-collision function that takes into account the kinematics of my robot and the environment in order to calculate if a configuration leads to a collision or not. Thanks in advance.

Answer 1

This is quite a vague question, but from what you provided I would suggest:

• Check how you are defining your C-Space. Do redundant configurations perform different collision checking?
• Take a look at the Flexible Collision Library - FCL . Maybe their framework guides you towards a proper arrangement of your overall joint system.
• Check the Open Motion Planning Library - OMPL . Combined with the FCL, you should be able to end up with a proper collision checking system for your arm.

Hope that helps.

Answer 2

solution

The arm should stop on Resistence(Torque increase) or detected Impact. Build the arm to be soft.

Alternative solution

Otherwise the Software can Check if the angle are close to the folddown position and stop moving further.