Modelagem, fabricação e validação de perfis geométricos em atuadores pneumáticos macios impressos para aplicação em dispositivos assistivos

Abstract

Soft robotics has increasingly been adopted for rehabilitation and assistive devices due to its compliance, safe physical interaction, and adaptability to human anatomy. This thesis proposes the development of Pneumatic Network (PneuNet) actuators fa- bricated in TPU 95A by fused deposition modeling (FDM) and evaluates their applicabi- lity to assistive devices by integrating hyperelastic modeling, finite element simulations, and experimental validation. Six geometries were investigated by combining three late- ral chamber profiles (triangular, circular, and rectangular) with two longitudinal profiles (straight and concave). The geometries were first screened via numerical simulations using an Ogden hyperelastic model, and after selecting the best-performing design (flat walls and rectangular profile), the chosen actuator was re-evaluated for TPU 95A using the Yeoh model to estimate bending response and stress under internal pressurization. The selected geometry was then manufactured and experimentally validated in terms of deformation and tip force using video-based analysis and load-cell measurements. The simulations reproduced the experimental trends, with mean errors of 3.8% for li- near displacement and 13% for bending angle, and tip forces on the order of 2.12 N at 200 kPa, despite the higher stiffness of TPU 95A. These results indicate that finite element modeling can support prototyping and that TPU 95A PneuNet actuators are feasible candidates for future low-cost assistive devices and active orthoses