Admittance Control-based Floating Base Reaction Mitigation for Limbed Climbing Robots

TL;DR

This paper introduces a novel admittance control scheme for legged climbing robots that reduces reaction forces and joint torques, enhancing stability and safety during complex terrain navigation and manipulation tasks.

Contribution

The paper presents a new position-based impedance control approach tailored for reaction force mitigation in climbing robots, validated through simulation studies.

Findings

Significant reduction in reaction forces during simulated disturbances

Decreased joint torque with the proposed control scheme

Improved stability in microgravity and steep terrain scenarios

Abstract

Reaction force-aware control is essential for legged climbing robots to ensure a safer and more stable operation. This becomes particularly crucial when navigating steep terrain or operating in microgravity environments, where excessive reaction forces may result in the loss of foot contact with the ground, leading to potential falls or floating over in microgravity. Furthermore, such robots are often tasked with manipulation activities, exposing them to external forces in addition to those generated during locomotion. To effectively handle such disturbances while maintaining precise motion trajectory tracking, we propose a novel control scheme based on position-based impedance control, also known as admittance control. We validated this control method through simulation-based case studies by intentionally introducing continuous and impact interference forces to simulate scenarios such as object manipulation or obstacle collisions. The results demonstrated a significant reduction in both the reaction force and joint torque when employing the proposed method.