ConTact Sensors: A Tactile Sensor Readily Integrable into Soft Robots

In this paper, we propose a soft robotics sensor that uses multiple modalities of sensing, fluid pressure and electrical resistance, of a single conductive fluid medium. Each modality responds differently to the same stimulus, allowing richer sensing than two distinct sensors would provide. We embody this concept into ConTact Sensor, a soft tactile sensor that can detect the force and contact length of the object compressing it. ConTact Sensor shares similar fabrication materials as most soft robotic designs, thus it can be combined with soft actuators or even embodied into a soft actuator itself. We detail the design, fabrication and characterization of ConTact Sensor and provide an example of integrating the sensor in a liquid-filled PneuNets actuator.