Quadrupedal Locomotion Control On Inclined Surfaces Using Collocation Method

TL;DR

This paper presents a novel control method for quadrupedal robots to walk on steep inclines up to 45 degrees by using a collocation approach with a reduced-order dynamic model, inspired by bird wing-assisted climbing.

Contribution

It introduces a collocation-based control strategy utilizing a reduced-order dynamic model to enable quadrupedal robots to traverse steep slopes efficiently.

Findings

Successfully demonstrated high-slope walking on 45-degree inclines.

Achieved rapid computation of optimal control actions.

Ensured ground contact forces comply with friction constraints.

Abstract

Inspired by Chukars wing-assisted incline running (WAIR), in this work, we employ a high-fidelity model of our Husky Carbon quadrupedal-legged robot to walk over steep slopes of up to 45 degrees. Chukars use the aerodynamic forces generated by their flapping wings to manipulate ground contact forces and traverse steep slopes and even overhangs. By exploiting the thrusters on Husky, we employed a collocation approach to rapidly resolving the joint and thruster actions. Our approach uses a polynomial approximation of the reduced-order dynamics of Husky, called HROM, to quickly and efficiently find optimal control actions that permit high-slope walking without violating friction cone conditions.