Automated design of underactuated monolithic soft robotics structures with multiple predefined end poses

Abstract

The increasing frequency of robot interactions with humans and complex environments motivates the design and control of soft robotic systems made of compliant structures. Additive manufacturing processes enable the creation of new robotic systems and mechanisms that gain their compliance extrinsically through their design, rather than simply their material. With the ability to rapidly and affordably manufacture such mechanisms, the interest in producing custom task-specific underactuated mechanisms has grown. These mechanisms may be useful for highly repetitive tasks or complex situations where the simplicity of control outweighs the versatility of a more traditional robotic system. In the course of this work, new underactuated monolithic soft robotic mechanisms are presented along with automated design processes. The structures can reach multiple arbitrary end effector poses and are controlled with as few actuators as possible. Two methods for the automated design of such structures via inverse kinematics and two concepts for the mechanical realization are presented. Several functional models were created to illustrate possible application scenarios and validate the mechanical concepts. A novel contact surface was also developed and shown to improve the accuracy performance of these structures. These automated design methods contribute toward the general accessibility and usability of multi-pose underactuated extrinsically soft mechanisms.