Development of Trajectories Through the Kalman Algorithm and Application to an Industrial Robot in the Automotive Industry

Abstract

This paper presents a method for optimizing the trajectories of robotic arms having manipulators with six degrees of freedom (DOFs) and spherical wrists. The trajectories are optimized by maximizing the manipulator performance (manipulability). For this purpose, kinematics models of the robot arms are defined, such that they can be integrated into an algorithm based on the Kalman filter. This algorithm is implemented through the simulation of trajectories in a serial industrial robot, which is a robotic arm with six DOFs and a fitted welding tool with a material contribution. During the trajectory optimization for such a manipulator robot, the orientation of the welding gun (e.g., the position of the final effector) must be preserved to guarantee correct welding. Applications of this method to two trajectories in the automotive industry are presented, and remarkable improvements in the performance of the manipulator itself are observed. The results obtained demonstrate that the proposed algorithm is an appropriate method for optimizing trajectories because of its various advantages, such as ease of implementation and states of calculation based only on the previous states. Therefore, this method allows the trajectories to be optimized in the work environment of the robot once the kinematic parameters of a robotic manipulator arm are known.