Novel Dynamic Performance Evaluation Indices of Hybrid Industrial Robots

Hybrid industrial robots have gained extensive attention due to the theoretical advantages of both serial robots and parallel robots. However, the multiple closed-loop structure makes its dynamic characteristics more complicated and the performance prediction more difficult, which leads to the limit of application. Taking a typical spray-painting robot as an example, this paper investigates the dynamic performance evaluation of hybrid industrial robots. The kinematic and dynamic modeling are performed first, and then two novel evaluation indices are proposed to evaluate joint-coupling effect and accelerating ability quantitatively. The simulations are performed to illustrate the change of the performance in the reachable workspace and time domain. The simulation results show that hybrid industrial robots have a strong dynamic coupling effect between joints at some poses. Moreover, the non-negligible joint friction leads to the reduction of the expected accelerating ability of joints, which may not meet the requirement of high-performance tasks.