Trajectory generation and tracking control methods for a multipletransfer robots system

摘要

This paper proposes trajectory generation and tracking controlmethods for the advanced transportation system METROS (Multiple TransferRobots System). The methods enable several transfer robots to transfermaterials cooperatively in an automated factory. The material'sreference trajectory guaranteeing smooth motions of robots isrepresented by simple combinations of line trajectories with constantvelocity profiles and transition ones with 8th order polynomials. Inorder to transfer the material stably along the reference trajectory, acooperative control architecture which consists of a master robot andslave ones is introduced. The master robot determines a behavior of thematerial for the specified reference trajectory, and thereafterdistributes the forces required to realize the desired behavior to theslaves. Each slave robot generates its own trajectory and controls thespeed and steering so as to exert the force commanded by the masterrobot. An impedance model is defined to determine the behavior of thematerial so that the material can behave as a desiredmass-spring-dashpot system. The simulation results justify both theproposed methods