Design and Development of Robot Hand System

Research on robot hand design is being carried out to accommodate a variety of tasks such as grasping and manipulation of objects in the field of industrial applications, service robots and rehabilitation robots. Problem statement: To design and develop a microcontroller-based four fingered robotic hand with a simple and minimal control strategy to pick and place application with object detection by simple IR sensor logic. Approach: The methodology is based on anthropomorphic design with three fingers and an opposing thumb. Each finger has three links and three double revolute joints. Each finger is actuated by a single opposing pair of tendons. The robot hand system is interfaced to microcontroller with software control by means of 14 independent commands for the motion of joints: close and open for fore finger, middle finger, ring finger and thumb finger and wrist up and down, base clockwise and counter clockwise, pick and place and home position. The tendoning system and wireless feedback logic provide the hand with the ability to confirm to object topology and therefore providing the advantage of using a simple control structure. Results: Reliable grasping and releasing is achieved with simple control mechanisms and IR sensors/push-button switches. The hand can pick a variety of objects with different surface characteristics and shapes without having to reconstruct its surface description. Picking of the object is successfully completed as long as the object is within the workspace of the hand and placed the object at the desired position within the workspace by relevant software control using keyboard commands. Conclusion: Hardware and software development of microcontroller-based four-fingered robotic hand is addressed. Details of hand control software for mainly pick and place applications are presented. Results of the experimental work for pick and place application of different objects is enumerated.