Soft Rotary Pneumatic Actuator
The Elastic Inflatable Actuators (EIAs) has several advantages such as the inherent compliance due to the body comprised of a soft materials such as silicone. Among them, the soft fiber reinforced actuator is based on the principle that the expansion of enclosure and constraint of fiber pattern lead to a desired operation. While lots of researches on the actuator has been attributed to linear and bending motions, however, there are only few researches on rotary, or torsional, motions.
we propose a new actuator that causes azimuthal deformation due to restriction of anisotropically distributed fiber element along the radial direction and expansion of the hyper elastic material. Structure design of the actuator and a fabrication process of the actuator are presented. Subsequently, FEM simulation and experiment are executed to measure rotation angles of the actuators corresponding to the applied pressure.
In the field of soft robots, jamming is being used in various fields. Looking at the use of previous jamming, jamming is a principle of obtaining the required stiffness by changing the stiffness of a joint, exoskeleton, or manipulator. There are many ways to use jamming, but it is not clear how to increase the efficiency of jamming. Therefore, research is needed to optimize the jamming effect.
The main goal of this study is to increase the stiffness by the jamming effect. In order to accomplish this study, we need to know about interactions between particles. The characteristics of particle interaction are analyzed through experiments. Furthermore, by studying the backbone mechanism, we optimize the stiffness by the jamming effect.
Series Elastic Actuator Using Scotch Yoke
Recently, Series Elastic Actuator(SEA) has been popularly used as a torque sensor thanks to its notable ability to calibrate the relation between torque and displacement. It has been applied to many robotic applications and used in a various industrial automation fields. However, most of the current SEAs have nonlinear torque-displacement characteristics which could not be easily alleviated. In order to be utilized as a feasible torque sensor, the wide linearity of a SEA in torque-displacement relationship is not an option. Also, adjustable compliance is needed to implement a mechanism with different stiffness, depending on the various cases where SEA can be applied.
We designed a Variable Stiffness Linear Series Elastic Actuator mechanism using the Scotch Yoke mechanisms which can achieve variable stiffness with a linear relationship between torque and displacement. Simulation of the designed model then verifies that the model can properly implement linearity and variable stiffness.