Tactile Interaction Sensor with Millimeter Sensing Acuity.

Eunsuk Choi,Sunjin Kim,Onejae Sul,Hojun Seo,Seung-Beck Lee,Minjin Kwon,Hyeonjeong Sun,Jinsil Gong

doi:10.3390/s21134274

Eunsuk Choi, Sunjin Kim + Show 6 more

Open Access

https://doi.org/10.3390/s21134274

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Abstract

In this article we report on a 3 × 3 mm tactile interaction sensor that is able to simultaneously detect pressure level, pressure distribution, and shear force direction. The sensor consists of multiple mechanical switches under a conducting diaphragm. An external stimulus is measured by the deflection of the diaphragm and the arrangement of mechanical switches, resulting in low noise, high reliability, and high uniformity. Our sensor is able to detect tactile forces as small as ~50 mgf along with the direction of the shear force. It also distinguishes whether there is a normal pressure during slip motion. We also succeed in detecting the contact shape and the contact motion, demonstrating potential applications in robotics and remote input interfaces. Since our sensor has a simple structure and its function depends only on sensor dimensions, not on an active sensing material, in comparison with previous tactile sensors, our sensor shows high uniformity and reliability for an array-type integration.

Highlights

The tactile sense of human fingers plays an essential role in object manipulation and interaction with a contacting object
Various tactile sensors have been developed for robotics and biomedical applications that have the ability to detect pressure magnitude, pressure distribution, and slip, similar to the human tactile senses [3,4,5]
MEMS tactile sensors have been widely used in robotics and electronics owing to their high reliability; their fabrication process is complex and expensive

Summary

Introduction

The tactile sense of human fingers plays an essential role in object manipulation and interaction with a contacting object. Various tactile sensors have been developed for robotics and biomedical applications that have the ability to detect pressure magnitude, pressure distribution, and slip, similar to the human tactile senses [3,4,5]. The tactile sensors with high sensitivity are based on nanomaterials, for example, carbon nanotubes or graphene as active sensing materials [24,25,26]. These nanomaterials showed high resistance change ratios on external stimulus; they lack applicability due to issues of non-uniformity and non-reproducibility [27]. To increase shear transfer characteristics, we used a PDMS layer with low modulus and an SU-8 ridge structure with high modulus [32]

Device Fabrication Fabrication Process

Shape and Motion Detection

Discussion

Conclusions