Quadruped mobile manipulators combine dexterous manipulation with omnidirectional mobility, but coordinating the motion of the robot body with the manipulator remains challenging, particularly when the manipulator end-effector is guided independently by a human operator or an autonomous system. This thesis presents a framework for controlling a quadruped mobile robot based on reactive end-effector tracking, in which velocity commands are generated in the local frame of the mobile robot. The proposed approach requires neither global localization nor motion planning and interfaces with the locomotion system only through forward, lateral, and yaw velocity commands. Three motion-allocation methods are investigated: a nonholonomic-priority method adapted from tracking methods developed for nonholonomic wheeled mobile platforms; a mixed-priority method that combines lateral motion and body rotation according to the end-effector position; and a holonomic-priority method centered around a prefered end-effector position. The framework is implemented in a simulation environment on a Unitree B2 quadruped equipped with a Unitree Z1 manipulator. Experimental evaluation demonstrates the feasibility of reactive arm–base coordination and reveals the trade-offs between maintaining the robot's orientation relative to the end-effector motion, minimizing the angular error between the robot orientation and the end-effector orientation, and maintaining symmetry of travelled distance.
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