Controle Coordenado de Movimento de um Sistema Robótico Redundante para Manufatura Aditiva com Arame e Arco

Abstract

This paper considers the trajectory tracking control of a robotic system for Wire Arc Additive Manufacturing (WAAM) of complex geometry parts. The considered (redundant) robotic system is composed by a robotic manipulator and a positioning table. In order to use the system redundancy, a task-priority based kinematic control scheme to control a manipulator and a positioning table coordinately is proposed. The manipulator and positioning table are considered as a single kinematic chain, defining the primary task as the trajectory tracking of the welding torch defined in the positioning table deposition frame and setting a secondary task to align the welding torch with a desired direction defined in the inertial frame (e.g., gravity direction). A complete Lyapunov stability analysis is performed considering unmodelled dynamics in the kinematic control loop. The effectiveness of the proposed method is shown experimentally on a WAAM robotic system composed of a six-axis industrial manipulator, a two-axis positioning table and a Cold Metal Transfer (CMT) power source.