How to set goal_threshold to allow small motions

[rr-dave]

Problem description:

• Send motoman a trajectory where all final joint values are within 0.01 radians (the default goal threshold) of the start joint values.
• This could be a significant cartesian motion, eg s joint at 1.5m reach: 1.5 x sin(0.01) = 15mm
• The trajectory is not sent to the robot because of the check here https://github.com/ros-industrial/motoman/blob/433be15f6a27cb9a5715cc3887b1cd15ff33a8cb/motoman_driver/src/industrial_robot_client/joint_trajectory_action.cpp#L337

I've previously experimented with changing the goal threshold and seen values less than 0.001 seem to time out, I suspect due to the joint 4 discrepancies identified in #592. Do you have any suggestions for how to make short trajectories execute? I'm considering trying to make only the initial check use a much tighter tolerance and leave the checks in controllerStateCB as they are.

[rr-dave]

This may be a duplicate of https://github.com/ros-industrial/motoman/discussions/467