Variable Recruitment in Bundles of Miniature Pneumatic Artificial Muscles and Space Qualified Pneumatic Artificial Muscles

The natural compliance and force generation properties of pneumatic artificial muscles (PAMs) allow them to operate like human muscles in anthropomorphic robotic manipulators. Traditionally, manipulators use a single PAM or multiple PAMs actuated in unison in place of a human muscle. However, these manipulators experience efficiency losses when operated outside their target performance ranges. The unidirectional actuation behavior of a miniature PAM bundle and bidirectional actuation behavior of an antagonistic pair of miniature PAM bundles are characterized and modeled. The results are used to motivate the application of a variable recruitment control strategy to a parallel bundle of miniature PAMs as an attempt to mimic the selective recruitment of motor units in a human muscle to improve the operating efficiency of the actuator. Additionally, the fabrication and quasi-static testing results for PAMs assembled from candidate space qualified bladder and braided sleeve materials for use in space robotics are assessed.

SUR Hand: A Soft Underactuated Robotic Hand

Soft robots are robots made mostly or completely of soft, deformable, or compliant materials. As humanoid robotic technology takes on a wider range of applications, it has become apparent that they could replace humans in dangerous environments. Current attempts to create robotic hands for these environments are very difficult and costly to manufacture. Therefore, a robotic hand made with simplistic architecture and cheap fabrication techniques is needed. The goal of this thesis is to detail the design, fabrication, modeling, and testing of the SUR Hand. The SUR Hand is a soft, underactuated robotic hand designed to be cheaper and easier to manufacture than conventional hands. Yet, it maintains much of their dexterity and precision. This thesis will detail the design process for the soft pneumatic fingers, compliant palm, and flexible wrist. It will also discuss a semi-empirical model for finger design and the creation and validation of grasping models.