Arm balancing experiments in the deadweight torque standard machine with adjustable lever-arm lengths.

Abstract

KRISS (Korea Research Institute of Standards and Science) has developed the 20 kN m-capacity deadweight torque standard machine that incorporates a double-arm design for the lever. Such a double-arm structure allows to separate two functions; supporting deadweight loads and determining effective lengths. One arm made of stainless steel supports the loads and the other made of INVAR determines the lever-arm length. Since the INVAR arm bears little loads, we could implement a translation mechanism in the INVAR torque arm to change its length in the range of approximately 6 mm. Using this unique feature of our machine, arm-balancing experiments have been conducted to investigate lever-arm length dependence on applied loads and determine the sensitivity of the air-bearing by intentionally unbalancing lengths on both sides to generate micro-torques under various loading conditions. In this paper, we present our plans of the experiments and discuss them. © 2018 Web Portal IOP. All rights reserved.