Optically Sensorized Elastomer Air Chamber for Proprioceptive Sensing of Soft Pneumatic Actuators

Soft robotics has proven the capability of robots interacting with their environments including humans by taking advantage of the property of high compliance in recent years. Soft pneumatic actuators are one of the most commonly used actuation systems in soft robotics. However, control of a highly compliant actuation system remains as a challenging issue due to its nonlinearity and hysteresis. Addressing this problem requires integration of a soft sensing mechanism with the actuator for proprioceptive feedback. A soft optical waveguide with a reflective metal coating is a promising sensing mechanism with high compliance and low hysteresis. In this letter, we propose design and fabrication of a soft pneumatic actuator integrated with an optical waveguide that can provide the proprioceptive information of the actuator. We describe the design and fabrication, and present experimental characterization results of the proposed system. We also provide applications of the proposed system.