Steering Wheel Angle Sensor, Basic Function - GF42.45-P-2005A
Model All (4xWD, CAR)
Example illustration of steering wheel angle sensor
Overview
This document contains information on:
- General
- Function
General
The steering wheel angle sensor (1) detects the current position of the steering wheel.
Function
The angle measurement is based on two evaluations:
- Code disk measurement for exact angle determination to 360°
- Turn measurement for absolute angle determination to ± 720°
View of lens body
Code disk measurement
The light emitted by one of the LEDs (7) integrated in the lens body (5) is deflected and parallelized by the optical fiber (6). The light shines through the punched code disk (4) and the PDA (3) can take a very accurate picture.
The PDA (3) converts the projected image of the code disk (4) into a digital data stream and forwards it for processing.
Turn measurement
The turn indicator (2) projects a focused light beam onto the PDA (3). Due to a worm gear, the position of the light beam on the PDA (3) depends on which turn the steering is currently in.
The absolute angle of the steering wheel is determined by combining the code disk measurement and the turn measurement. The steering wheel angle is recorded with a resolution of 0.1° and a scanning rate of 100 Hz (scan duration of 10 ms). The steering wheel angle sensor (1) provides the steering column tube module control unit with a voltage signal that is proportional to the steering wheel angle.