Design of Deformable Joystick with Isotropic Stiffness Utilizing High Elongation Strain Sensor

Abstract

In this paper, a new type of joystick with isotropic stiffness is presented. Due to the deformable design where high elongation is expected, a typical strain sensor is unsuitable. Therefore, a new type of high elongation strain sensor with high sensitivity developed in BioMEMS Lab is first evaluated as a strain sensor and then used for deformation estimation for a simple deformable body. Then, a joystick design with isotropic stiffness was designed, simulated, and tested using flexible silicone rubber. The design, while showing good isotropic stiffness performance in simulation did not do so during the experiments, partly due to a number of estimations and limitations placed in the finite element model. This research shows the feasibility of using a combination of a deformable body for isotropic stiffness and high elongation sensors for deformation estimation. Further research is needed in regards to deformation estimation algorithms and refinements in the finite element model for more refined deformable joystick designs.