High Precision Accelerometer with Integrated Thermal Sensor

Abstract

This paper investigates the design of a Vibrating Beam Accelerometer (VBA) with a resolution of 50 nano-g combined with an integrated thermal sensor. Despite quartz intrinsic thermal stability, the time delay between vibrating beam’s temperature and package’s temperature gives way to unwanted transient thermal behavior and thus bias instability. The aim of this study is to include a thermal sensor consisting in a torsional resonator directly at the center of the beam. Previous work demonstrated the feasibility of such integration on a tactical class accelerometer but also highlighted limitations like high motional resistance of the torsional resonator. Benefits of the in-situ temperature sensor are investigated thanks to finite element analysis of the accelerometer transient thermal behavior, which shall be compared to measurements on actual cells.

Keywords

• VBA
• in-situ thermal sensor
• transient thermal behavior
• finite element analysis