Abstract
As interest in nursing-care robots continues to grow, not only safety and reliability but also low acoustic noise and energy-saving performance are expected. In this paper, we describe our prototype of a robotic arm. The prototype is a link mechanism using magnetic particle brakes at each joint in place of servo motors. The magnetic particle brakes are proportional torque devices controlled by varying the excitation current. The link mechanism can hold up a target object and passively support a positioning action. The dynamics of the prototype are analyzed first, and then the self-weight compensation and the resistance torque display to support the positioning action are realized by appropriate actuation of the magnetic particle brakes.
