Design of a two degree of freedom robotic finger

Abstract

The design of mechanical hands has been investigated at many universities. Most of the hands produced by their research have large actuator packs which are usually heavy and located remotely from the hand. They are also complex to control A number of robotic hand designs are reviewed and their shortcomings are discussed briefly. A feasibility study in 1993 at the University of Canterbury on a mechanically linked finger was used as the starting point for the design of a new finger - the Canterbury finger. Several combinations of electric drive motors, gearboxes, lead screws and mechanical linkages were examined before the final configuration was selected. The result is a human sized finger and hand capable of exerting a reasonable force at the finger tip, and able to curl through 180° in two distinct motions. While the dexterity typical of tendon operated fingers is retained, the new design avoids the elasticity and friction problems of tendon operated hands. A single mechanically linked two degree-of-freedom (DOF) finger was designed, built and tested. The design and performance criteria were met, and the working finger provided insight into areas for improvement and future development. This thesis includes manufacturing drawings, test results, and basic control software for the Canterbury finger.