INVERSE KINEMATICS OF BINARY MANIPULATORS USING A CONTINUUM MODEL

Binary actuators have only two discrete states, both of which are stab le without feedback. As a result, manipulators with binary actuators h ave a finite number of states. The major benefits of binary actuation are that extensive feedback control is not required, reliability and t ask repeatability are very high, and two-slate actuators are generally very inexpensive, resulting in low cost robotic mechanisms. These man ipulators have great potential for use in both the manufacturing and s ervice sectors, where the cost of high performance robotic manipulator s is often difficult to justify. The most difficult challenge with a b inary manipulator is to achieve relatively continuous end-effector tra jectories given the discrete nature of binary actuation. Since the num ber of configurations attainable by binary manipulators grows exponent ially in the number of actuated degrees of freedom, calculation of inv erse kinematics by direct enumeration of joint states and calculation of forward kinematics is not feasible in the highly actuated case. Thi s paper presents an efficient method for performing binary manipulator inverse kinematics and trajectory planning based on having the binary manipulator shape adhere closely to a time-varying curve. In this way the configuration of the arm does not exhibit drastic changes as the end effector follows a discrete trajectory.