SelfCollisionBarrier to avoid robotic arm hitting itself?

[MichaelRazum]

Hi there,

Given a urdf file with specified collision.

What would be the right approach, to avoid the robot hitting itself (or go through itself) ?
Is using SelfCollisionBarrier the right way to do it?

I also tried to modify the code in examples/arm_ur5.py and adding (line 52)

robot.collision_model.addAllCollisionPairs()
collision_barrier = SelfCollisionBarrier(
    n_collision_pairs=len(robot.collision_model.collisionPairs),
    gain=20.0,
    safe_displacement_gain=1.0,
    d_min=0.05,
)
barriers = [collision_barrier]
configuration = pink.Configuration(robot.model, robot.data, q_ref,
                                   collision_model=robot.collision_model,
                                   # Collision model is required for self_collision_barrier
                                   collision_data=robot.collision_data, )

I then added barriers to the solver. However, in this case, the process dies with exit code 139 (interrupted by signal 11: SIGSEGV). I suspect that the configuration is entirely wrong in the way I wrote it here.

Would be grateful for any hint!

[stephane-caron]

You can take a look at the self-collision examples in the examples/barriers directory. Those should be closer to what you are looking for here:

• kukas_self_collision.py: whole-body self-collision avoidance
• yumi_self_collision.py: self-collision avoidance with spheres

For a single-arm you can just skip the dual-arm duplication step at the beginning of these scripts.