Optimal Paint Gun Orientation in Spray Paint Applications—Experimental Results

In this paper, we present the experimental results of a new spray paint algorithm presented in previous publications. Both theory and simulations indicate that the proposed method allows a robotic manipulator to paint a given surface using substantially lower joint torques than with conventional approaches. In this paper, we confirm this by implementing the algorithm on an ABB robot and we find that the joint torques needed to follow the trajectory are substantially lower than for the conventional approach. The approach presented is based on the observation that a small error in the orientation of the end effector does not affect the quality of the paint job. It is far more important to maintain constant velocity for the entire trajectory. We thus propose to allow a small error in the specification of the end-effector orientation, and we show how this allows us to obtain a higher constant speed throughout the trajectory. In addition, to improve the uniformity of the paint coating we are also able perform the paint job in less time.