A family of nonlinear PID-like regulators for a class of torque-driven robot manipulators equipped with torque-constrained actuators

oleh: Adriana Salinas, Javier Moreno-Valenzuela, Rafael Kelly

Format: Article
Diterbitkan: SAGE Publishing 2016-02-01

Deskripsi

This article addresses the joint position control of torque-driven robot manipulators under actuators subject to torque saturation. Robots having viscous friction, but without gravity vector, are considered. By assuming a static model for the torque actuator (specifically, a model of nonlinear and non-differentiable hard saturation function), a family of nonlinear proportional–integral–derivative-like controllers is proposed. Lyapunov stability theory is used to establish conditions for local asymptotic stability of the closed-loop system. A notable feature of the proposed controller is that stability conditions do not depend on the saturation levels of the actuators. In addition, an experimental study complements the proposed theory.