Effects of Limb Morphology on Transient Locomotion in Quadruped Robots

Abstract

The natural world hosts a few mammals that display both a high degree of agility and speed. However these animals have complex leg morphologies. Robot designers are thus faced with the dilemma of which morphology to employ when designing the next generation of agile legged robots. Thus this letter presents a novel investigation into the effects of limb morphology of quadrupeds during rapid transient maneuvers such as acceleration and deceleration. Three leg configurations inspired by nature (O-, X-Type and All-Ankle) as well as All-Knee configurations are compared. Extensive large scale Monte Carlo simulations utilizing contact-implicit trajectory optimization methods were employed on 100 randomly generated robots of varying sizes to determine the optimal configuration for the task of rapid transient locomotion. After extensive analysis, the investigation revealed that an X-Type leg configuration outperformed all other configurations. Ultimately, these results will provide insight for the mechanical design of future agile quadruped robots.