Development of a Bio-inspired Soft Robotic Gripper based on Tensegrity Structures
Yixiang Liu, Qing Bi, Yibin Li
Abstract
The bones, muscles, tendons and connective tissues form a continuous tension network throughout human body. This heterogeneous mixture presents the characteristics of tensegrity, providing the body with structurally integrity, stability and flexibility. Inspired by this, this paper proposes a novel soft robotic gripper based on tensegrity structures. Firstly, the design and working principle of the tensegrity-based robotic gripper is introduced, which is composed of a series of discrete rigid segments connected with tensegrity joints by means of tensional cables. Then, the kinematics of the robotic gripper is analyzed using force density method to obtain the relationship between the pose of the gripper and the tension of cables. Finally experiments on the developed prototype demonstrates that the robotic gripper is able to grasp various objects of different sizes, shapes, and materials. Additional desirable properties are derived from using tensegrity structures in the robotic gripper: light weight, high compliance, inherent safety, low cost, and waterproof and dustproof performance. It is suggested that tensegrity structures have great potential to be an effective alternative to the development of soft robotic grippers.