The Research And Development Of Torque And Angle Integrated Detection Sensor For The Automobile EPS

Electric power steering (EPS) system is a kind of motor driven steering technology. It has the advantage of simple structure, easy installation and maintenance, low consumption, well environmental protection and control nicely. It is more important that EPS can adjust the assistance force according to vehicle speed and ensure the drive obtaining enough road information. EPS system is the future of automobile steering technology. It accords with the desire of automobile technology electronization. The steering wheel sensor is one of the key component of the EPS system, and the performance of the sensor is very important to the EPS. The steering torque and angle are the vital parameters of the vehicle especially which equipped with EPS. It is the inevitable trend of integrating the torque and angle into a solo-sensor in the development of vehicle technology. And the integrated sensor will greatly promote the development of EPS. Therefore, to design and manufacture a kind of integrated sensor measure structure which is consistent with the EPS system needs is very necessary.Based on the learning from domestic and foreign research literature, this dissertation puts forward a integrated sensor detection scheme which includes angle measurement by a set of gear meshing method and torque detection by torsion shaft indirect measurement. Then follow the scheme, the integrated sensor’s structure and minimum hardware circuit system based on Freescale MC9S08DZ60MCU are designed. In order to actualize the sensor detection function, the sensor software program is designed on the basis of detection algorithm analysis. Finally, the R&D EPS torque and angle integrated sensor performance is validated by some related experiments, including angle contrast test, driving motor test and the hardware in the loop test which carried out on the electric power steering test-bed. It is validated that whether the self-designed EPS torque and angle integrated sensor can meet the basic functional requirements of EPS equipment by analyzing the test data and charts.