Development of Single-Axis Wheel Speed Sensor HiL Test Bench for Vehicle Velocity Control

The precise measurement and processing of dynamic vehicle data lays the foundation for modern active safety systems and driver assistance systems for automobiles and two-wheelers. For the determination of the longitudinal vehicle dynamics, sensing the wheel speed is one elementary measured quantity. This paper proposes a Hardware in the Loop (HiL) test bench that is used for the development and evaluation of a velocity measurement, consisting of two redundant magneto-resistive sensor elements and an encoder disk. This is intended to precisely determine the vehicle velocity on the rear axle (single axis) of scooters with an engine displacement of 50 cubic centimeters. Therefore, a stepper motor powers the encoder disk on which two sensors are placed. An Electronic Control Unit (ECU) manages the measurement, the motor control, the Human Machine Interface (HMI) and the real-time communication through a serial interface to the computer, running the simulation. To represent the virtual test vehicle, the mathematical model is integrated into Matlab Simulink. The test bench was developed under the criteria of low cost, small size and different operating modes.