Folding Angle Control of Inter-Connected Pouch Motors

Recently, planar pneumatic actuators, known as pouch motors, have gained attention in the fields of soft robotics and Human-Computer Interaction (HCI). However, achieving complex 3D shapes by pouch motors has been hindered by two challenges: (1) the slow operating speed of customized CNC machines, conventionally used for pouch fabrication and (2) the lack of control over the folding angle of individual pouches. To overcome these limitations, (1') we introduce the use of a laser cutter to fabricate pouch motors. This approach enhances the fabrication process, enabling faster production of the pouch motors. Additionally, (2') we propose laser-welding patterns that incorporate small barriers to control the folding angle of each pouch. By manipulating the welding patterns, we achieve nearly linear control over the folding angle of the pouches. In this paper, we present the design and fabrication process of laser-welded planar pneumatic actuators and showcase several design examples.