Stiffness analysis of double tendon underactuated fingers

Underactuated mechanisms are commonly used in robotic hands and grippers to improve their ability to adapt to the shape of an object. These underactuated mechanisms can be characterized by their global stiffness as measured by their actuator. Using this with self-adaptive fingers, it is possible to elaborate equations highlighting the relationship between the stiffness measurements and the contact locations. In this paper, a complete stiffness analysis of a general double tendon underactuated finger is performed with the aim of establishing the contact locations without any tactile sensors.