# Robust Whole-Body Motion Control of Legged Robots

## TL;DR

This paper presents a robust whole-body motion control architecture for legged robots that ensures stability and performance despite model uncertainties and delays, verified on a quadruped robot.

## Contribution

It introduces a robust contact force control method combined with task space decomposition for improved stability and performance in legged robot control.

## Key findings

- Robust control guarantees stability despite model mismatches and delays.
- Task space decomposition reduces coupling effects between controllers.
- Experimental validation shows improved performance over standard inverse dynamics.

## Abstract

We introduce a robust control architecture for the whole-body motion control of torque controlled robots with arms and legs. The method is based on the robust control of contact forces in order to track a planned Center of Mass trajectory. Its appeal lies in the ability to guarantee robust stability and performance despite rigid body model mismatch, actuator dynamics, delays, contact surface stiffness, and unobserved ground profiles. Furthermore, we introduce a task space decomposition approach which removes the coupling effects between contact force controller and the other non-contact controllers. Finally, we verify our control performance on a quadruped robot and compare its performance to a standard inverse dynamics approach on hardware.