Collision detection and identification for a legged manipulator

TL;DR

This paper presents a collision detection and force estimation framework for quadrupedal robots, enhancing safety and accuracy through novel filtering and compensation techniques validated by extensive hardware experiments.

Contribution

It introduces a new collision detection pipeline that estimates collision time span and improves force magnitude accuracy by compensating for model inaccuracies and disturbances.

Findings

Accurate collision detection using band-pass filtering.

Enhanced force estimation through compensation methods.

Validated framework in diverse real-world scenarios.

Abstract

To safely deploy legged robots in the real world it is necessary to provide them with the ability to reliably detect unexpected contacts and accurately estimate the corresponding contact force. In this paper, we propose a collision detection and identification pipeline for a quadrupedal manipulator. We first introduce an approach to estimate the collision time span based on band-pass filtering and show that this information is key for obtaining accurate collision force estimates. We then improve the accuracy of the identified force magnitude by compensating for model inaccuracies, unmodeled loads, and any other potential source of quasi-static disturbances acting on the robot. We validate our framework with extensive hardware experiments in various scenarios, including trotting and additional unmodeled load on the robot.