The influence of 3D printing parameters on pellet-extruded hyperelastic polymers for cost-efficient soft gripping with encapsulated sensors

Abstract

Recent advances in pellet-extrusion Fused Filament Fabrication (FFF) allow the robust and repeatable 3D printing of materials exhibiting hyperelastic mechanical properties. This study links process parameters such as temperature and printing speed to the mechanical response of hyperelastic structures, as well as to their dimensional accuracy. Three materials of varied hardness, TPU 75 Shore A, TPV 63 Shore A and TPS 30 Shore A, are investigated experimentally for their strength and elasticity, with manufacturing defects further highlighted by analysis under a Scanning Electron Microscope (SEM). The cost-efficient nature of pellet-extrusion FFF lends itself to applications within soft robotic manipulation, with a case study on complian gripping included in this effort. Leveraging the versatility of FFF towards process pauses and subsequent post-processing, standard sensor components for measuring angle and force are mounted into cavities during and after the print, respectively. The encapsulated sensors validate numerical simulations on the gripper topology, qualifying the force response and object detection capability over 50 use-cycles.

Keywords: 3D printing, pellet extrusion, hyperelastic materials, soft gripping

DOI: 10.54941/ahfe1005161