Small-Sized Deformable Shear Sensor Array for Direct Monitoring of Quantitative Shear Distribution

An array of shear sensors is essential in tactile sensation as well as the pressure sensors. Surprisingly, however, the shear sensor array is rarely investigated mainly due to the structural complexity to measure the horizontal forces from various directions and also due to the mechanical softness required for preventing the slip of an object. Here, an array of small shear sensors that can recognize both shear force and shear rotational angle is fabricated. All the device components are made of deformable materials to acquire the softness of the sensor. This work presents a novel design for the small-sized shear sensor array and the required material conditions for the design. By using an ion gel as the capacitive sensing material, the shear sensor array shows high sensitivity and excellent reliability under repeated shear forces. This work demonstrates playing computer game with the shear sensor and sensing the frictional force distribution, which is possible through the recognition of multiple shear stimuli and spatial shear distribution (force, rotational angle) when static/dynamic shear forces are simultaneously applied from various directions.