Measurement and Analysis of End Jitter of Six-Axis Industrial Robots.

In this manuscript, the force hammer excitation method was employed to measure and analyze the intrinsic frequency of the six-axis industrial robot. The end jitter of the robot under different working conditions was tested with the help of the end jitter testing platform, and the trajectory that minimized the end jitter amplitude was obtained by comparing the end displacement of different trajectories at the same speed. Furthermore, in order to investigate the impact of each single joint rotation on end jitter, the end jitter caused by independent rotation of each joint was measured, and it was found that the rotation of joint 2 and joint 3 caused larger jitter than others for the tested robot. Finally, the single-joint rotation self-power spectrum was used to derive the dominant frequency in the low frequency range during single-joint rotation and the relationship between end jitter and robot resonance was analyzed.