An adaptive nonlinear estimator for the MEMS capacitive accelerometer based on adaptive input-output feedback linearization

This paper presents a new estimator for the conventional capacitive MEMS accelerometer. This scheme is realized by adding an adaptive nonlinear observer to a conventional PID closed loop system. This estimator is used for online estimation of the parameter variations for MEMS accelerometers and gives the capability of self testing to the system. We outline the design of an online estimator for a capacitive MEMS accelerometer to detect changes in spring stiffness (k) and damping factor (b).