Does anyone know where i could find more information about the underlying path planning algorithms behind the movej and movel functions? I would like to understand how the function calculates all the required joint positions, velocity and accelerations required to reach the given waypoints. Is it simply a minimum jerk trajectory calculation for movej and a linear path planing algorithm for movel or is there something more going on?
I don’t know the specifics for the UR so this might not be helpful.
In general, the easiest/naive implementation of a moveJ command is to run inverse kinematics to compute the joint values at the destination, and then command each joint independently to move as fast as possible to the destination pose, therefore the trajectory ends up being almost a linear interpolation in joint space.
for moveL the naive implementation is to move all joints such that the tool position stays on the line connecting the starting point to the end point, running inverse kinematics 100 times a second or more to compute the next small steps for all joints to make.