How soft does a robot need to be? Design analysis and optimization of compliant robots for controlled tasks

Thesis tree

Compared to traditional robots, soft and compliant robotic designs are well-suited for manipulating objects and interacting with the environment because they reduce the need for accuracy and precision in motion. My thesis work contributes to the field of soft robotics by tackling the question of how to intelligently integrate compliance into robot design as well as how to fabricate and control soft robots for many tasks. I demonstrate how programmatic design, enabled by my advances in soft fabrication, modeling, and control techniques, can provide novel soft robotic manipulation and locomotion systems.

My thesis advances soft fabrication through the development of casting and printing techniques, novel actuator morphologies, and embedded actuation modalities. Models developed for soft robots enable object identi cation through deformation and dexterous manipulation under contact. Control algorithms developed for soft robots realize open-loop locomotion control, closed-loop manipulation, and grasp planning. An automatic design procedure concatenates actuator morphologies together and generates a soft robotic manipulator with heterogeneous material distribution and customized geometries optimized for a desired manipulation task.

These techniques are combined in designs that include a soft robotic fi sh, a soft robotic hand, a soft juggling robot, and a soft robotic arm. I use modular soft designs to create robotic fish for underwater locomotion and proprioceptive hand designs and manipulator arms for object manipulation. I develop a cyclic pump systems for undulating soft actuators and an embedded system design process to create an autonomous soft fish robot that receives remote acoustic commands to explore oceanic life. A proprioceptive soft robotic hand grasps a wide range of objects and performs haptic object identi cation by conforming to their shapes. Dynamic object manipulation with a soft surface is enabled through modeling soft contacts and by applying model-based control. Closed-loop controlled manipulator arms perform autonomous grasps, move in confi ned spaces and perform manipulation under contact.