A Novel Lockable Spring-loaded Prismatic Spine to Support Agile Quadrupedal Locomotion

TL;DR

This paper presents a new lockable spring-loaded spine module for quadrupedal robots, enabling systematic study of compliance effects on locomotion and demonstrating benefits in impact absorption during landing.

Contribution

Introduction of a novel lockable spring-loaded spine module and a new quadruped platform for empirical and numerical analysis of spinal compliance effects.

Findings

Comparable jumping performance with rigid and compliant spines

Compliant spine absorbs impact energy during landing

Spine's locking mechanism is compact and effective

Abstract

This paper introduces a way to systematically investigate the effect of compliant prismatic spines in quadrupedal robot locomotion. We develop a novel spring-loaded lockable spine module, together with a new Spinal Compliance-Integrated Quadruped (SCIQ) platform for both empirical and numerical research. Individual spine tests reveal beneficial spinal characteristics like a degressive spring, and validate the efficacy of a proposed compact locking/unlocking mechanism for the spine. Benchmark vertical jumping and landing tests with our robot show comparable jumping performance between the rigid and compliant spines. An observed advantage of the compliant spine module is that it can alleviate more challenging landing conditions by absorbing impact energy and dissipating the remainder via feet slipping through much in cat-like stretching fashion.