Development of force-balance accelerometer with high accuracy for precision motion measurement

Abstract

A precision force balancing accelerometer for inertial navigation applications is developed. The low-sensitivity threshold and high thermal stability are considered as design parameters. In order to guarantee a low-sensitivity threshold while maintaining robustness against shock, push-pull type long flexures are used in this paper. To improve thermal stability, this paper discusses the use of electromagnets as a magnetic field source and develops the silicon case together with the temperature compensator. The silicon pendulum assembly and the modified inductance type pick-up is also developed to reduce assembling procedure. After assembling the accelerometer, static tests are carried out. Static tests show a sensitivity threshold of 4.6 x 10(-5) g and a maximum measurement range of +/-24 g. The push-pull type long flexures reduce spring constant considerably.