Safe, Passive Control for Mechanical Systems with Application to Physical Human-Robot Interactions

TL;DR

This paper introduces a new safe, passive control law for mechanical systems that ensures safety and passivity during human-robot interactions, allowing flexible control within safety constraints and demonstrated on a 6-DOF robot.

Contribution

A novel closed-form control method that guarantees safety and passivity in physical human-robot interactions, compatible with any nominal control law.

Findings

Effective safety enforcement during human-robot interaction

Control law maintains passivity under external perturbations

Demonstrated on a 6-DOF robot with successful results

Abstract

In this paper, we propose a novel safe, passive, and robust control law for mechanical systems. The proposed approach addresses safety from a physical human-robot interaction perspective, where a robot must not only stay inside a pre-defined region, but respect velocity constraints and ensure passivity with respect to external perturbations that may arise from a human or the environment. The proposed control is written in closed-form, behaves well even during singular configurations, and allows any nominal control law to be applied inside the operating region as long as the safety requirements (e.g., velocity) are adhered to. The proposed method is implemented on a 6-DOF robot to demonstrate its effectiveness during a physical human-robot interaction task.