Force/Position Control of 3 DOF Delta Manipulator with Voice Coil Actuator

Abstract

Parallel manipulators are widely used in the industries for several applications. Due to its precision in motion as well as its robustness, parallel manipulators have proved its advantage over serial manipulators. In this paper, a 3DOF parallel manipulator is presented and force control of the manipulator is demonstrated. The proposed manipulator uses a direct drive voice coil arc actuators to achieve compliance required for human-robot interaction or soft mechanical manipulations. Its implementation in the proposed delta manipulator is discussed in the paper. The paper has discussed a unique method of controlling position as well as the force at the end-effector of the delta manipulator. The method used in making the manipulator compliant does not need an explicit force sensor and is convenient to implement. The method is inexpensive and works satisfactorily in a human interactive environment which is demonstrated through experiments discussed in the paper. The proposed design finds its application in robot-assisted assembly, surface finishing, cooperative manipulation, haptics etc.