Curve Tracking Control for Legged Locomotion in Horizontal Plane

TL;DR

This paper develops a hybrid feedback control law for legged robots to follow curved paths in the horizontal plane, adjusting leg placement and elasticity for stable, directed locomotion.

Contribution

It introduces a novel control law for the lateral leg spring model that enables curved path following and orientation stabilization in legged locomotion.

Findings

Achieves stable curved path following using feedback of curvature, bearing, and distance.

Defines constraints on leg parameters for feasible curves.

Derives an optimal control law for body orientation stabilization.

Abstract

We derive a hybrid feedback control law for the lateral leg spring (LLS) model so that the center of mass of a legged runner follows a curved path in horizontal plane. The control law enables the runner to change the placement and the elasticity of its legs to move in a desired direction. Stable motion along a curved path is achieved using curvature, bearing and relative distance between the runner and the curve as feedback. Constraints on leg parameters determine the class of curves that can be followed. We also derive an optimal control law that stabilizes the orientation of the runner's body relative to the velocity of the runner's center of mass.