DESIGN AND DEVELOPMENT OF A 5 DOF SERIAL MANIPULATION

Abstract

The primary objective of designing the hand exoskeleton is to include a controllable degree of freedom (Degree of Freedom) of the finger joints with minimum number of actuation modes. This paper describes the design and development of a multi Degree of Freedom handexoskeleton based on the rehabilitation criteria of an amputee to achieve different hand gestures on the passive amputee hand. The problems regarding designing the hand exoskeleton are the interlinked constraints which primarily includes the cost, weight and complexity parameters. There are many designs in this particular field which were focused on these parameters. This design contains 3 Degree of Freedom, 5 fingered links with the inclusion of thumb and a separate flexion and extension of the wrist joint. The rotation between each of the joint is carried through rigid connecting rods with only 1 degree of freedom which converts the translation motion into rotary motion. The force applied to the end effectors is through lead screw mechanism which is attached to the MCP joint and the connecting rods transmit the power to the end effectors. The direction of motion of these independent finger links is controlled by the rotation of motor and a current feedback sensor which helps in perfect gripping of the object. This hand exoskeleton can work for the assistive humanoid robotics for the physiotherapy sessions and also to provide different hand gestures including the pinch and power gripping. After several sessions with the physiotherapist, a chart will be formulated with the data collected from the amount of disability travelled to the hand and all the necessary physiotherapy gestures required for the exercise and improving the hand and by adding different classes the therapy sessions can be carried out in the home providing the patient to take the “doctor” with home.