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In this paper, we will present a torque and angle sensor for use in electrical power steering (EPS) systems. The developed sensor has torsion angle sensing capabilities between the input and output shafts linked by a torsion bar as well as multi-turn angle sensing of the steering wheel. The sensor is technically based on inductive position sensing for torque measurement and magnetic position sensing for additional multi-turn angle measurement. Digital output single edge nibble transmission (SENT) and pulse width modulation (PWM) are applied to strengthen noise performance in an automotive environment and enhance diagnostic capabilities. The torque channel consists of two electrically isolated sensors that can function independently. The angle channel also has five redundancies using angle information from inductive and magnetic channels during operation, even though there is only one reference signal for initialization.

This paper describes our development work for acceleration sensing modules for electronic stability program (ESP) applications. The accelerometer is fabricated using the unique sacrificial/bulk micromachining (SBM) process by us. The sensing modules are designed to measure low level accelerations accurately and be stable in an automotive environment. This paper describes the accelerometer design and fabrication, electronic circuits and PCB design, module assembly, and performances of the developed sensing module. The developed sensing module offers analog voltage output with ±1.5g dynamic range, 0.05% nonlinearity, >50Hz bandwidth and 1295mV/g scale factor. The module includes a CAN2.0A interface and yields good experimental performance when implemented on a CAN test server.