In soft robotics, gripper technology based on granular jamming offers the capability to adapt flexibly to objects of diverse shapes and material properties. Specifically, small-scale jamming grippers can address tasks challenging for conventional grippers either by enhancing gripping performance or by extending functionality when combined with rigid grippers. This study investigated effects of membrane morphology, thickness, and material on performances of small-scale jamming grippers to identify optimal design parameters. Experiments were conducted with three membrane morphologies, two thickness levels, and two material types. Results indicated that a concentric-pocket membrane morphology, a membrane thickness of 1.5 mm, and a soft material such as Dragon Skin 10 achieved a superior holding force of 430.7 gf. These findings indicate that softer materials can improve the membrane's ability to conform to objects, while increasing thickness can minimize deformation due to tensile forces, thereby enhancing gripping stability. Furthermore, experiments demonstrated that this configuration could enable the gripper to safely grasp objects of various shapes and perform additional tasks, such as rotating valves and handles, with effectiveness.

In this paper, Finite Element Analysis (FEA) for gear heat treatment using simultaneous dual frequency (SDF) induction heating is conducted. To do this, thermal-electromagnetic coupled FE model is built. A two dimensional FE model of gear and heater is introduced to reduce computation time. For more time-efficient analysis, harmonic analysis for electromagnetic model is adopted and transient analysis model, for heat transfer model. Through the coupled analysis, it can be found that the proposed FE model can solve for SDF induction heating of gear and heat treatment parameters can also be determined.