Sensor Reduction, Estimation, and Control of an Upper-Limb Exoskeleton

A multi-degree-of-freedom (multi-DOF) exoskeleton relies on an array of sensors to communicate its state (e.g., positions/orientations) and operator-exoskeleton contact interactions forces/torques) control system. Although sensor redundancy is common in biological systems cope with uncertainty partial failure sensors, man-made systems, increases the overall system's cost complexity. This study presents a reduction technique for force/torque (F/T) utilizing Kalman filter-based fusion system context admittance control. The methodology applied EXO-UL8 exoskeleton, which powered, redundant, dual-arm, upper-limb robotic (7 arm + 1 hand) DOFs incorporating three 6-axis F/T each arm. Motivated by improving wearability through minimizing human-exoskeleton interfaces, reduces spurious forces due joint misalignment; reducing cost, proposed strategy emulates controller's virtual dynamics only subset resulting physical human-robot interaction feeling same from operator's perspective. Experimental results indicate that power exchange actuation stresses joints, two are comparable those full three-sensor case (p <; 0.01). experiments verify EXO-UL8, support feasibility operating other fewer without sacrificing transparency interaction.