Dynamics and control of a differential drive robot with wheel slip: application to coordination of multiple robots Shyamprasad Konduri Graduate Research Assistant, Student Member of ASME Department of Mechanical Engineering Texas A and M University College Station, Texas 77843 Email: konduri@tamu.edu Edison Orlando Cobos Torres Graduate Research Assistant, Student Member of ASME Department of Mechanical Engineering Texas A and M University College Station, Texas 77843 Email: orlando.cobos@tamu.edu Prabhakar R. Pagilla ∗ Professor, Fellow of ASME Department of Mechanical Engineering Texas A and M University College Station, Texas 77843 Email: ppagilla@tamu.edu ABSTRACT In differential drive robots wheel slip severely affects the ability to track a desired motion trajectory, and the problem is exacerbated when differential drive robots are used in applications involving coordination of multiple robots. This problem is investigated and based on the wheel-ground traction forces a simple slip avoidance control strategy is discussed. Differential drive robots with two driven wheels and one or more ball-type caster wheels are considered. The traction forces between the wheels and the ground surface are determined by assuming rigid wheel, rigid ground interaction. These traction forces are used to determine the maximum value of the input wheel torque that can be applied on the wheel before it slips. To avoid wheel slip, this limiting torque value is used to set a saturation limit for the input torque computed by a trajectory tracking controller. Stability of the closed loop system ∗ Address all correspondence related to ASME style format and figures to this author. Pagilla DS-15-1628 1 Journal of Dynamic Systems, Measurement and Control. Received December 08, 2015; Accepted manuscript posted September 22, 2016. doi:10.1115/1.4034779 Copyright (c) 2016 by ASME Accepted Manuscript Not Copyedited Downloaded From: http://dynamicsystems.asmedigitalcollection.asme.org/ on 10/14/2016 Terms of Use: http://www.asme.org/about-asme/terms-of-use