Open-loop pressure estimation for hydraulic control unit of vehicle electronic stability control system

A vehicle electronic stability control(ESC) hardware-in-loop(HiL) test bed and an ESC test car were established to form a platform for ESC system research and development.A hydraulic model was built for the ESC hydraulic control unit(HCU) and its parameters were calibrated according to the hydraulic characteristics acquired by tests on the ESC HiL test bed.Based on the acquired hydraulic characteristics of HCU,the open-loop estimation of the wheel cylinder pressure was performed.On the basis of this estimation,a closed-loop pressure estimation algorithm was downloaded to the ESC test car platform to do the ESC test.The test results showed that the proposed pressure estimation algorithm can provide accurate and reliable wheel cylinder pressure estimation values during braking force distribution for the vehicle with ESC system.