A Cable-Driven Robotic Arm (CDRA) possesses a number of advantages over the conventional articulated robotic arms, such as lightweight mechanical structure, high payload, fault tolerance, and most importantly, safe manipulation in the human environment. As such, a mobile manipulator that consists of a mobile base and a CDRA can be a promising assistive robot for the aging or disabled people to perform necessary tasks in their daily life. For such applications, a CDRA is a dexterous manipulator that consists of a number of cable-driven joint modules. In this chapter, a modular design concept is employed in order to simplify design, analysis, and control of CDRA to a manageable level. In particular, a 2-DOF cable-driven joint module is proposed as the basic building block of a CDRA. The critical design analysis issues pertaining to the kinematics analysis, tension analysis, and workspace-based design optimization of the 2-DOF cable-driven joint module are discussed. As a modular CDRA can be constructed into various configurations, a configuration-independent kinematic modeling approach based on the Product-of-Exponentials (POE) formula is proposed. The effectiveness of the proposed design analysis algorithms are demonstrated through simulation examples.
Development of a Direct-Drive Servovalve Using a Giant Magnetostrictive Material.
