A novel multi-point trajectory generator for robotic manipulators based on piecewise motion profile and series-parallel analytical strategy

A novel time-optimal multi-point trajectory generator (TMTG) based on piecewise motion profile and series-parallel analytical strategy is proposed for robotic manipulators to improve the motion accuracy and efficiency. The multi-point trajectory is composed of various subtrajectories to eliminate overshoot and undershoot according to the constrained velocity direction at the desired points. The piecewise motion profile is acted as a fundamental subtrajectory model for a jerkcontinuous subtrajectory. A series-parallel analytical strategy provides a closed-form solution for the time-optimal multi-point trajectories. The series analytical strategy for a single-joint trajectory generates the time-optimal trajectory and the upper velocities of the desired points. The parallel analytical strategy for multi-joint subtrajectories synchronizes the joint movements to enhance the multi-joint motion accuracy. The simulations and experiments conducted on a manipulator validate that TMTG outperforms state-of-the-art approaches in terms of accuracy and efficiency for a multi-joint manipulator. The absolute position errors of all joint by TMTG at the end of motion are within 0.007 degrees. Therefore, TMTG is a functional solution for manipulators to construct time-optimal multi-point trajectories.

Automated summary

A novel time-optimal multi-point trajectory generator (TMTG) is proposed to improve the motion accuracy and efficiency of robotic manipulators. The TMTG utilizes a piecewise motion profile and a series-parallel analytical strategy to generate optimal trajectories. It eliminates overshoot and undershoot by composing the trajectory of various subtrajectories according to constrained velocity direction. The simulations and experiments demonstrate that TMTG outperforms existing approaches in terms of accuracy and efficiency for multi-joint manipulators, with absolute position errors within 0.007 degrees at the end of motion.