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This report describes the calibration of accelerometers. The theory for the calibration is based on acceleration as a vector quantity, and the sensitivity derived by the theory is defined as a matrix. The experiment was conducted using a three-dimensional vibration generator and three one-channel laser interferometers. The accelerometer used in the experiment is a three-axis type. Comparison with the conventional calibration method places an importance on the transverse sensitivities, because their influence on the acceleration measurement is impossible to disregard. The relation between the transverse sensitivities derived by the matrix concept and the conventional transverse sensitivities defined by ISO-5347 Part 11 is stated. Importance of the dimension of the motion space created by the vibration generator is stated in terms of the calibration.

This paper proposes a novel fabrication technique of TiNi shape memory alloy (SMA) film and verifies the validity by showing the actual fabrication process and the final results. Special attention is paid to the characterization of differential scanning calorimetry (DSC). An essential part of the fabrication process is the co-sputtering from separate pure Ti and Ni targets. Co-sputtering is carried out using a multi-target sputtering system where RF power for each target can be controlled independently. As-sputtered film is vacuum-annealed. The phase transformation behavior of the fabricated film is investigated by DSC and temperature-controlled X-ray diffractometry (XRD). Finally, shape recovery behavior is observed. The proposed novel fabrication technique is validated by these results.

This report presents a novel method for characterizing accelerometers under medium and high accelerations ranging from 2 × 10 2 to 1 × 10 6 m s −2 . The reflection of longitudinal elastic waves in a thin circular bar is used for the excitation of a test accelerometer that is attached to the end of the bar. A newly designed laser interferometer can determine the input acceleration accurately. By improving the resolution of the interferometer, the lower acceleration limit of this method can be extended from 2000 m s −2 , the previous limit, to 200 m s −2 . The effectiveness of the method is confirmed through an experiment in which a piezoelectric-type accelerometer is characterized.

This paper presents a new method of estimating the dynamic characteristics of a shock accelerometer using elastic wave propagation in a metal bar. The output from the accelerometer attached to a Davis bar is compared with the theoretical acceleration calculated using the relationship derived from the one-dimensional wave equation of motion in elastic media. The experiment was carried out using the 2 m long stainless steel bar, a solenoid valve air gun, a transient recorder, and a personal computer for signal processing. Details are given of the experimental equipment, the comparison of the accelerometer output with the differentiation of the strain gauge signal, the comparison of the integration of the acceleration signal with the strain gauge signal, and the response curve of the accelerometer calculated using the fast Fourier transform.