[ Papers ]

Journal of the Korean Society of Manufacturing Technology Engineers - Vol. 27, No. 6, pp.517-523

ISSN: 2508-5093 (Print) 2508-5107 (Online)

Print publication date 15 Dec 2018

Received 03 Oct 2018 Revised 06 Nov 2018 Accepted 09 Nov 2018

DOI: https://doi.org/10.7735/ksmte.2018.27.6.517

단차에 대한 촉각 인지 역치 측정

정지연^a ; 조영학^b ; 황지홍^b^{, *}

Absolute Threshold in Tactile Sensing of Step by Fingertip

Jiyeon Jung^a ; Young Hak Cho^b ; Jihong Hwang^b^{, *}

aResearch Center for Die and Mould Technology, Seoul National University of Science and Technology 232 Gongneung-ro, Nowon-gu, Seoul 01811, Korea
bDepartment of Mechanical System Design Engineering, Seoul National University of Science and Technology, 232 Gongneung-ro, Nowon-gu, Seoul 01811, Korea

Correspondence to: ^*Tel.: +82-2-970-6396 Fax: +82-2-976-5173 E-mail address: hwangjh@seoultech.ac.kr (Jihong Hwang).

Abstract

The presence of steps on the surface of a product is a typical example of deteriorating product quality. Therefore, it is required to lower their heights to a level that a human cannot perceive. In this context, the present study focuses on experimentally measuring the minimum perceptible step height (absolute threshold). For this purpose, step samples with heights less than 3 μm were made from silicon wafers using a microelectromechanical systems (MEMS) fabrication technique with an accuracy under 10 nm. The experiment was performed using the method of constant stimuli. The participants were instructed to touch the samples using their index fingers, and then answer whether they perceived the steps or not. After analyzing the data statistically, it was concluded that the absolute threshold is about 1.35 μm when the finger moves in the direction parallel to the finger and about 2.04 μm in the direction perpendicular to the finger.

Keywords:

Step, Tactile sensing, Absolute threshold, Method of constant stimuli

Acknowledgments

이 연구는 서울과학기술대학교 교내 학술연구비 지원으로 수행되었습니다.

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