Later this year, I (or one of my colleagues) will be involved in a project that involves a KUKA robot which is mounted on a linear axis, so that it can slide back and forth. I have only seen this configuration in videos, so I am not sure how it is controlled from the robot program.
Can anyone here tell me how it works? I can see in the .dat file from our KUKA robot, that each taught position also contains data about the position of up to 6 external axes, E1-E6. I assume that the robot is moved on the linear axis by changing the value of E1 (for instance).
But does this mean that the robot never activates the linear axis unless specifically told to do so? I mean, if the robot is told to move to a point that is outside of its reach, will it automatically move along the linear axis in order to be able to reach?
If the robot is able to move along the axis on its own (i.e. without being told to do so), then it means that the inverse kinematics solver in the robot has to find an inverse kinematics solution for a 7-axis robot. There are infinitely many solutions to this problem. How does the solver choose one of the solutions? Is there some sort of weight function involved?
Also: Do the tcp-coordinates on the teach-pendant change when the robot is moved along the axis, or does the robot not know that it is moving, but only that it has an external axis?
And finally: If the tcp-coordinates on the teach-pendant change when the robot moves along the axis, then it means that the direction of the axis is known to the robot. How is the robot and the axis co-calibrated? Or is there only one way of mounting the robot on the axis, and therefore no need for calibration?
Thanks in advance!