WMR Kinematic Control Using Underactuated Mechanisms for Goal Direction and Evasion
Jorge U. Reyes-Muñoz, Edgar A. Martínez‐García, Ricardo Rodríguez Jorge, Rafael Torres-Córdoba · InTech eBooks · 2017
This work presents the mechanical design and the kinematic navigation control system for a tricycle-wheeled robot (one drive-steer and two lateral fixed passive) with two underactuated mechanisms: a global compass and local evasive compass. The proposed goal-reference mechanism is inspired by the ancient Chinese south-seeking chariot (c. 200–265 CE) used as a navigation compass. The passive lateral wheels transmit an absolute angle from its differential speeds to automatically steer the front wheel. An obstacle-evasive compass mechanism is commutated for steering control when detecting nearby obstacles. The absolute and local compass mechanisms commutate each other to control to the robot’s steering wheel to reach a goal while avoiding collisions. A kinematic control law is described in terms of the robot’s geometric constraints and is combined with a set of first-order partial derivatives that allows interaction between the global and local steering mechanisms. Animated simulations and numerical computations about the robot’s mechanisms and trajectories in multi-obstacle scenarios validate the proposed kinematic control system and its feasibility.