Guidelines for cogwheel design optimized for back-bias speed sensor applications

Wheel speed sensors are commonly used in automotive applications where knowledge of the precise rotational velocity of the wheels is required to determine the vehicle speed or to obtain subtle information about tire pressure, road conditions or to steer modern driver assistance systems like the Electronic Stability Program. The conventional back-bias speed sensor solution requires the design of a proper target wheel that gives an optimal signal for specific, respective applications and magnetic sensors. In this work, typical geometric and material parameters of the cogwheel are identified and their influences on the speed signal are analyzed in detail. Data is acquired by finite element simulations that give an excellent understanding of how the speed signal behaves with a variation of the critical model parameters. The performed studies aim to provide guidelines for cogwheel manufacturers and for system engineers on how such wheels can be optimized for diverse applications.