This paper describes the dynamic characteristics of a binocular six-component force-moment sensor with force components Fx, Fy and Fz, each having 200 N capacity, and moment components Mx, My and Mz, each having 20 N m capacity. We have evaluated the dynamic characteristics of the force-moment sensor by using a shaker system and a multichannel dynamic analyser system. It reveals that the sensitivity decreases as the frequency increases and that the sensor shows almost 90° symmetry due to its geometry.

This paper describes the dynamic characteristics of a three-component force-moment sensor with the transverse forces Fx and Fy each having 200 N capacity and a twisting moment Mz of 10 N m capacity. We have evaluated the dynamic characteristics of the force-moment sensor by using a shaker system and a multi-channel dynamic analyser system. It reveals that the sensitivity decreases as the frequency increases and that the sensor has a 90° symmetry due to its geometry.

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This paper describes the development of a three-component force/moment sensor with plate-beams which may be used for measuring the forces F x, Fy and the moment Mz simultaneously in industry. In order to make the three-component force/moment sensor, the following procedures are performed. (1) Derivation of equations to predict the bending strains on the surfaces of the plate-beams under the forces or the moments. (2) Determination of the sizes of the sensing elements of the force/moment sensor using the derived equations.(3) Finite Element Method (FEM) analysis for confirming the strains from the theory. ( 4) Selection of the attachment locations of the strain gauges of each sensor. (5) Fabrication of the three-component force/moment sensor. ( 6) Characteristic test of the three-component force/moment sensor. The rated strains calculated from the derived equations agree well with the results from the FEM analysis and the experiments. The interference errors of each sensor are less than 1.7%.

When a build-up system is placed into a deadweight force-standard machine, the signals from the force transducers contain oscillation components that reflect the dynamic behaviour of the force machine. The deadweight force-standard machine of 100 kN at the Korea Research Institute of Standards and Science (KRISS) causes oscillations with component frequencies of about 0.28 Hz. These are strongly related to the pendulum motion of the deadweights. This paper describes the behaviour of the deadweights in detail. The oscillation frequency, as well as the trajectory of the pendulum motion, is investigated. Some signal-processing methods that are designed to estimate the dynamic behaviour of the deadweights, by using the force signals from the build-up system, are proposed. The relative uncertainty due to the motion of the deadweight is estimated. This paper also deals with a modification of the deadweight force machine that is designed to reduce its pendulum motion significantly.

This paper describes the dynamic behaviour of a dead-weight force-standard machine at the Korea Research Institute of Standards and Science (KRISS). When a build-up system is set into a dead-weight machine, the signals from the force transducers in the build-up system consist of a dc component and oscillating signal components. The dominant oscillating components are due to pendulum motions of the dead weights and bounce-mode oscillation. The oscillation frequencies are about 0.19-0.23 Hz for the pendulum motions and 0.67-1.42 Hz for the bounce-mode oscillation. The frequencies decrease as the weights loaded are increased. The time-averaging technique is the simplest method for reducing the ac components. However, it has some limitations in that the averaging time must be re-adjusted according to the loading conditions. Other methods of reducing the ac components are therefore required. We introduced an infinite-impulse-response (IIR) low-pass filter, which reduced the oscillating components dramatically for all loading conditions. The results obtained by using IIR filtering were compared with those of time averaging and shown to be better.