Design and manufacturing of a miniature pneumatic actuator for a bat robot

Abstract

There have been many pneumatic actuator designs created over the past several years. One such design consists of multiple, completely separated air cells that when pressurized, expand and push off one another causing the actuator to bend. With this chamber design, the actuator requires a small change in volume to deform, effectively leading to improved reliability and increased actuation speed. Other design characteristics such as cross section geometry, inner/outer wall thickness ratio, distance between cells, cell height, and material selection can be modified to optimize the actuator’s performance. Incorporating this design into the bat robot allowed for greater soft robotic ear deformation, however it is too large for this application. To see if it was possible to reduce the size of the actuator while maintaining its functionality, several adjustments were iteratively made to previously described mold designs. Manufacturing remained a two-step process, but removable side walls and a filter-ventilation system were added to allow for the silicone, used to cast the actuator, to fully cure. Ultimately, the actuator produced maintained its expected functionality and was produced at a smaller scale than originally thought possible.