Trajectory Tracking for Robotic Arms with Input Saturation and Only Position Measurements

TL;DR

This paper introduces a passivity-based control method for robotic arms that achieves trajectory tracking using only position data, with natural input saturation and no need for velocity observers, validated through experiments.

Contribution

The paper presents a novel control approach that handles input saturation and eliminates the need for velocity measurements or observers in robotic arms.

Findings

Effective trajectory tracking demonstrated on Philips Robot Arm

Controllers naturally saturated without additional mechanisms

Lyapunov-based analysis confirms convergence

Abstract

In this work, we propose a passivity-based control approach that addresses the trajectory tracking problem for a class of mechanical systems that comprises a broad range of robotic arms. The resulting controllers can be naturally saturated and do not require velocity measurements. Moreover, the proposed methodology does not require the implementation of observers, and the structure of the closed-loop system permits the identification of a Lyapunov function, which eases the convergence analysis. To corroborate the effectiveness of the methodology, we perform experiments with the Philips Experimental Robot Arm.