Design of a Multi-Directional Hybrid-Locomotion Modular Robot With Feedforward Stability Control

Abstract

This paper presents the design of a modular robot capable of multi-directional mobility to aid reconfiguration on uneven terrain. Modular reconfigurable robotic systems consist of a large number of self-sufficient modules that can dock and reconfigure to scale locomotion and manipulation capabilities. However, on uneven terrains, reconfigurable robots face challenges due to the requirement of precise alignment between modules during the docking procedure. First, a survey of current modular reconfigurable robots is presented, analyzing their strengths and shortcomings in reconfiguration and mobility. A novel design is formulated that features a hybrid combination of wheels and tracks, symmetrically assembled about the front and right planes, providing multi-directional mobility and modularity. The robot can move over uneven terrain via tracks, move at higher speeds via wheels placed orthogonally to the tracks, and move in the vertical direction via a vertical translation mechanism in order to aid in multi-robot docking. Both the wheels and tracks possess yaw mobility via differential drive. The design’s compact size and hybrid multi-directional mobility system make the robot highly mobile on uneven terrain. Presented in this paper are the mechanical and electrical design and a feedforward dynamic stability controller, the performance of which is validated using a simulated case study.