Design of Feedback Loop for Ultra-sensitive Nano-g Resolution MEMS Tunneling Accelerometer

Abstract

The tunneling accelerometer often used for attitude control of micro and nano satellite can be operated both in open loop circuit as well as close loop circuit. Closed-loop operation improves the overall sensor linearity, dynamic range, and bandwidth. The interface circuitry in a closed-loop device reads the sensor signal and uses feedback to maintain the proof mass in a null position in a stable manner. In this paper we present a design and modeling of a PID (Proportional Integral Derivative) Controller for the feedback control of an ultra-sensitive MEMS (Microelectromechanical System) Tunneling Accelerometer to operate in constant current mode which will reduce the system response time, the fatigue of the accelerometer and increase the system stability.

Keywords: Tunneling accelerometer, MEMS, PID controller, force balance technique