title: Contact Pressure Level Indication Using Stepped Output Tactile Sensors.
abstract: In this article, we report on a novel diaphragm-type tactile pressure sensor that produces stepwise output currents depending on varying low contact pressures. When contact pressures are applied to the stepped output tactile sensor (SOTS), the sensor's suspended diaphragm makes contact with the substrate, which completes a circuit by connecting resistive current paths. Then the contact area, and therefore the number of current paths, would determine the stepped output current produced. This mechanism allows SOTS to have high signal-to-noise ratio (>20 dB) in the 3-500 Hz frequency range at contact pressures below 15 kPa. Moreover, since the sensor's operation does not depend on a material's pressure-dependent electrical properties, the SOTS is able to demonstrate high reproducibility and reliability. By forming a 4 × 4 array of SOTS with a surface bump structure, we demonstrated shear sensing as well as surface (1 × 1 cm²) pressure mapping capabilities.
authors.affiliation: Department of Electronic Engineering, Hanyang University, 222 Wangsimni-ro, Seongdong-gu, Seoul 133-791, Korea. silver77@hanyang.ac.kr.
authors.forename: Eunsuk
authors.initials: E
authors.lastname: Choi
authors.affiliation: Institute of Nano Science and Technology, Hanyang University, 222 Wangsimni-ro, Seongdong-gu, Seoul 133-791, Korea. ojsul@hanyang.ac.kr.
authors.forename: Onejae
authors.initials: O
authors.lastname: Sul
authors.affiliation: Department of Electronic Engineering, Hanyang University, 222 Wangsimni-ro, Seongdong-gu, Seoul 133-791, Korea. jywhat@hanyang.ac.kr.
authors.forename: Juyoung
authors.initials: J
authors.lastname: Kim
authors.affiliation: Department of Electronic Engineering, Hanyang University, 222 Wangsimni-ro, Seongdong-gu, Seoul 133-791, Korea. skylab7@hanyang.ac.kr.
authors.forename: Kyumin
authors.initials: K
authors.lastname: Kim
authors.affiliation: Department of Electronic Engineering, Hanyang University, 222 Wangsimni-ro, Seongdong-gu, Seoul 133-791, Korea. kjskim383@hanyang.ac.kr.
authors.forename: Jong-Seok
authors.initials: JS
authors.lastname: Kim
authors.affiliation: Department of Electronic Engineering, Hanyang University, 222 Wangsimni-ro, Seongdong-gu, Seoul 133-791, Korea. dy.kwon87@gmail.com.
authors.forename: Dae-Yong
authors.initials: DY
authors.lastname: Kwon
authors.affiliation: Department of Electronic Engineering, Hanyang University, 222 Wangsimni-ro, Seongdong-gu, Seoul 133-791, Korea. bdchoi@hanyang.ac.kr.
authors.forename: Byong-Deok
authors.initials: BD
authors.lastname: Choi
authors.affiliation: Department of Electronic Engineering, Hanyang University, 222 Wangsimni-ro, Seongdong-gu, Seoul 133-791, Korea. sbl22@hanyang.ac.kr.|Institute of Nano Science and Technology, Hanyang University, 222 Wangsimni-ro, Seongdong-gu, Seoul 133-791, Korea. sbl22@hanyang.ac.kr.
authors.forename: Seung-Beck
authors.initials: SB
authors.lastname: Lee
keywords: spatially digitized electrode; stepped output characteristics; tactile sensor; tactile sensor array