Choi, Dong-Eun Lee, Woosub Hong, Seong Hun Kang, Sung-Chul Lee, Hyeongcheol Cho, Chang-Hyun 2024-01-20T08:30:43Z 2024-01-20T08:30:43Z 2021-09-02 2014-12 2234-7593 https://pubs.kist.re.kr/handle/201004/126078 This study presents a passively variable threshold torque Spring-Clutch (PVSC). When human beings and robots work together as in the service robot example, physical safety of the former should be guaranteed. A passive mechanism is usually preferred because of its high reliability and fast response to collision. The PVSC comprises the Spring-Clutch mechanism (in that a spring and cam are utilized for generating threshold torque), and an adjuster (an additional cam and lever mechanism to adjust the threshold torque). It functions as a rigid joint between the input and output. However, when the applied torque exceeds the threshold value, the PVSC joint is fully released and becomes freely rotatable to guarantee safety during contact. The threshold torque is passively adjusted according to the gravitational torque and, therefore, a constant releasing torque is maintained for all joint rotation angles. The threshold torque of the PVSC increases (or decreases) in response to the variation in the deflection of the spring (achieved by using the adjuster) according to the rotation angle (or gravitational torque). Experiments were performed and the PVSC was implemented in the second joint of the SS-Arm IV. English KOREAN SOC PRECISION ENG FRIENDLY ROBOT DESIGN ACTUATION APPROACH ACTIVE COMPLIANCE STIFFNESS Design of safe joint with variable threshold torque Article 10.1007/s12541-014-0621-5 1 INTERNATIONAL JOURNAL OF PRECISION ENGINEERING AND MANUFACTURING, v.15, no.12, pp.2507 - 2512 INTERNATIONAL JOURNAL OF PRECISION ENGINEERING AND MANUFACTURING 15 12 2507 2512 scie scopus kci ART001930734 000346166800004 2-s2.0-84916899708 Engineering, Manufacturing Engineering, Mechanical Engineering Article FRIENDLY ROBOT DESIGN ACTUATION APPROACH ACTIVE COMPLIANCE STIFFNESS Cam Passive mechanism Safe joint Spring clutch