Design and Control of a Large Modular Robot Hexapod

Abstract

Legged robotic systems have made great strides in recent years, but unlike wheeled robots, limbed locomotion does not scale well. Long legs demand huge torques, driving up actuator size and onboard battery mass. This relationship results in massive structures that lack the safety, portability, and controllability of their smaller limbed counterparts. Innovative transmission design paired with unconventional controller paradigms are the keys to breaking this trend. The Titan 6 project endeavors to build a set of self-sufficient modular joints unified by a novel control architecture to create a spiderlike robot with two-meter legs that is robust, field-repairable, and an order of magnitude lighter than similarly sized systems. This thesis explores how we transformed desired behaviors into a set of workable design constraints, discusses our prototypes in the context of the project and the field, describes how our controller leverages compliance to improve stability, and delves into the electromechanical designs for these modular actuators that enable Titan 6 to be both light and strong.