Novel Soft-Rigid Hybrid Robotics Approach Enabled via Multilayered Bellow-type Soft Pneumatic Actuator

Soft robotics is an emerging field characterized by compliant and adaptable structures, presents unique challenges and opportunities for technological advancements. The thesis provided herein aimed to explore various soft robotic actuators and address critical limitations by proposing a novel Soft-Rigid Hybrid (SRH) approach. The study encompassed ideation, conceptualization, investigation, and the sharing of a multi-staged development of SRH robotics approach. Following an extensive literature review and analysis of various soft actuators, multilayered bellow-shaped soft pneumatic actuators (MBSPAs) were selected as a basis for investigation, for their for their potential compatibility with the SRH approach. The first stage of development involved a thorough examination of the working principles and fabrication methods for layered soft pneumatic actuators, leading to the creation of the Thermoplastic Polyurethane Multilayered Bellow-shaped Soft Pneumatic Actuator (TPU-MBSPA). The TPU-MBSPA demonstrated highly efficient displacement motion, with key design variables and fabrication details documented in the thesis and submitted as a journal article to contribute to the expanding field of soft robotics. To further advance our understanding of the TPU-MBSPA and facilitate numerical simulations, extensive material characterization was conducted. Uniaxial tensile tests and additional investigations were employed to validate simplifications, isotropicity, and temperature independence. A numerical simulation model, based on experimentally obtained material data, accurately predicted the expansion performance of the TPU-MBSPA. Additional exploration of an alternative application as a displacement sensor showcased the versatility and potential applications of the TPU-MBSPA beyond its primary function. With the TPU-MBSPA as the foundation, the study progressed to address limitations in the state-of-the-art soft grippers by introducing SRH Revolute Joint Actuator (SRH-RJA) and SRH Prismatic Joint Actuator (SRH-PJA). Detailed philosophies, designs, and constructions of these joint actuators were presented. Through iterative designs, the occurrence of radial bulging in SRH-RJA was mitigated using bio-inspired armadillo-casing and embedded casing methods, leading to significant improvements in force output. The choice of materials for the rigid components was justified based on practicality. The novelty, efficiency, and superiority of the proposed joint actuators were