Simultaneous Detection of Displacement, Rotation Angle, and Contact Pressure Using Sandpaper Molded Elastomer Based Triple Electrode Sensor

Abstract

In this article, we report on a flexible sensor based on a sandpaper molded elastomer that simultaneously detects planar displacement, rotation angle, and vertical contact pressure. When displacement, rotation, and contact pressure are applied, the contact area between the translating top elastomer electrode and the stationary three bottom electrodes change characteristically depending on the movement, making it possible to distinguish between them. The sandpaper molded undulating surface of the elastomer reduces friction at the contact allowing the sensor not to affect the movement during measurement. The sensor showed a 0.25 mm−1 displacement sensitivity with a ±33 μm accuracy, a 0.027 degree−1 of rotation sensitivity with ~0.95 degree accuracy, and a 4.96 kP−1 of pressure sensitivity. For possible application to joint movement detection, we demonstrated that our sensor effectively detected the up-and-down motion of a human forefinger and the bending and straightening motion of a human arm.

Synergy of porous and air-gap structures for pressure sensing arrays with high sensitivity and wide detection range towards machine learning-assisted gait analysis

“…Another method to improve the performance of pressure sensors is to design reasonable microstructure, which can be divided into internal microstructures and external microstructures. The internal microstructures of the sensors include porous structures [27], crack structures [28], hollow structures [29] and so on, and the external microstructures include micropillars [30], microridges [31], micropyramids [32], folds [33], hemisphere [34] and so on. For example, Zhuang et al [35] took advantage of the characteristics of micropores formed between grains during selective laser sintering processing to introduce microporous structures into thermoplastic polyurethane (TPU)/carbon nanotube (CNT) sensing elements, and prepared a flexible pressure sensor with three-dimensional porous conductive structure.…”

Multimodal Capacitive and Piezoresistive Sensor for Simultaneous Measurement of Multiple Forces

“…Stretchable and wearable sensors are attracting immense attention because of their great potential in human health monitoring and robotics. − Recently there have been significant advances in flexible sensors capable of either very high sensitivity − or high stretchability mimicking human skin, , with a few showing both high sensitivity and stretchability. − However, most tactile sensor systems reported to date are generally for a single loading mode and cannot distinguish multidirectional loads as human skin can, such as normal and shear forces. , Directional and highly sensitive tactile sensors are needed for robotic and dexterous manipulation to detect slippage during grasping tasks − and to provide important information on the shape and surface texture of the object and the friction between the skin and the object. For these applications, it is critical to spatiotemporally determine the magnitudes and directions of contact forces so as to resolve the spatial distribution of normal and tangential (shear) stresses during contact.…”

Two-Dimensional Micro-/Nanoradian Angle Generator with High Resolution and Repeatability Based on Piezo-Driven Double-Axis Flexure Hinge and Three Capacitive Sensors

“…The angle is one of the most important basic geometrical quantities in the field of precision engineering [ 1 , 2 , 3 , 4 ]. Various microangle measurement instruments, such as the angle encoder [ 5 , 6 , 7 ], autocollimator [ 8 , 9 ], and angle interferometer [ 10 ], are commonly used in scientific research and industrial metrology to provide accurate angle reference values within the feedback loop of manufacturing and testing processes.…”