LOW COST SILICON ACCELEROMETER

RESEARCH TO DESIGN AND DEVELOP A LOW COST INERTIAL GRADE SILICON ACCELEROMETER IS PROPOSED HERE. THE MAIN OBJECTIVE OF THE EFFORT IS TO SHOW THAT IT IS POSSIBLE TO BUILD AN ACCELEROMETER ON A SINGLE CRYSTAL SILICON CHIP, CAPABLE OF HANDLING MID-COURSE GUIDANCE REQUIREMENTS OF A MISSILE. A SILICON WAFER IS CHEMICALLY ETCHED THROUGH A MULTI-STAGE PROCESS TO YIELD TORSIONALLY FLEXIBLE HINGE FLEXURES SUPPORTING A PROOF MASS. THE ACCELEROMETER UTILIZES A CAPACITIVE PICK-OFF TO MEASURE THE DEFLECTION OF THE PROOF MASS. THE PICK-OFF SIGNAL IS AMPLIFIED AND FED TO RESTORING CONTROLLER WHICH DRIVES THE ELECTROSTATIC FORCER TO COUNTER THE INERTIAL FORCE ACTING ON THE PROOF MASS. THE SIGNAL DIFFERENTIAL VOLTAGE INPUT TO THE FORCER IS A DIRECT MEASURE OF THE APPLIED ACCELERATION. A DETAILED DESIGN ANALYSIS WILL BE PERFORMED BEFORE BUILDING AN ENGINEERING MODEL OF THE ACCELEROMETER.