Macro model analysis of a single mass 6-DOF Inertial Measurement Unit system
Résumé
In this paper, a preliminary analysis of a 6-axis micromachined Inertial Measurement Unit (IMU) structure is performed. We firstly give a review of current approaches found in literature for 6-axis IMU sensor technology. Then, we present and analyze the proposed single mass macro model structure. We mainly investigate the simultaneous detection of all possible six axis motion components with a single bloc based on SMSD approach. The angular velocity detection method is based on the Coriolis Effect which requires a certain translation applied to a suspended mass attached to a piezoelectric membrane. Two methods have been examined: first one is based on the Eigenfrequencies of the membrane, and second one is based on the inverse piezoelectric effect to actuate the membrane. So, electrodes deposited on the piezoelectric membrane are employed for sensing and actuating mechanisms based on direct/reverse piezoelectric effects. As a primary investigation, a modal analysis of the IMU macro model consisting of a piezoelectric Buzzer is presented. FEM simulations and measurement values show a good agreement. Applied stress on the membrane submitted to a linear acceleration is evaluated and improved designs, allowing 3 to 4 times higher stress values, are investigated.