RS9000, a novel MEMS accelerometer family for Mil/Aerospace and safety critical applications

Abstract

Mid accuracy navigation and control systems require gyros and accelerometer to predict the position of a moving object in free space. Accelerometers are used to perform initial levelling and correct the gyro drift on the move. Typically, accelerometer with a range of ±10g with overall bias stability better than 2 mg and scale factor composite repeatability of better than 1000 ppm is required for the AHRS application. Current solutions in the market are mainly based on either vibrating quartz structures or traditional precision mechanics. These solutions suffer from high cost and fragility. MEMS is an inherently rugged technology and has great potential to bring forth novel solutions on the harsh environment and safety critical applications and enable new solutions due to its size, ruggedness and potential cost benefits. We report a new technological platform termed IRIS™ and a new accelerometer product based on that is called RS9000 family. RS9000 is interfaced with an open-loop electronic circuit and is comprised of a novel MEMS element designed specifically for high bias stability. RS9010 is a ±10g accelerometer with in run bias stability of better than 120µg, long term composite bias repeatability of better than 1.5mg, scale factor repeatability of 400ppm and vibration rectification of better than 65µg/g2. To our knowledge, this is the highest accuracy reported for a MEMS sensor operating in open-loop.