Task priority based dual-trajectory control for redundant mobile manipulators

This paper presents a novel control system for redundant mobile manipulators to track simultaneously separate mobile platform and end-effector trajectories. Two Joint-dependent control variables are introduced to the task vector. These two control variables are D and α, where D is the Euclidean distance between the end-effector´s, and the mobile platform´s frames origins, and α is the angle of the end-effector position vector relative to the mobile platform´s frame. A singularity-robust task-priority inverse with gradient projection method is used to find solutions of a dual-trajectory tracking while, at the same time, maximize the manipulability measure for the robotic arm. MATLAB Simulation is used to test and optimize the proposed control system. The results demonstrate the effectiveness of the control system in alternating the order of priority between the two trajectories and optimizing the arm manipulability measure.