Research And Implementation Of Adaptive Anti-pinch Control System For Car Windows

Modern cars basically realize the electric control of windows,which brings convenience to passengers,but also has potential safety risk.Due to the huge lifting force in the process of window closing,it is easy to cause the accident of pinch when the passengers do not pay attention to it.Therefore,the car is required to have the function of window anti pinch.At present,most of the mainstream anti pinch controllers use photoelectric or Hall sensors,but the sensor dependent anti pinch control module not only has the problems of high hardware cost,complex structure and inconvenient installation,but also its stability is easily affected by the external environment,such as temperature change,mechanical wear,road vibration,etc It may cause serious consequences of anti pinch misjudgment.In this paper,the defects of the current anti pinch controller are improved.In the hardware design,by extracting the current ripple signal of the window DC motor instead of the sensor,two methods are proposed to obtain the position and speed information of the window,which are FFT processing method of the current ripple signal and hardware conversion method of the current ripple to pulse wave.This paper also deeply studies the anti pinch control algorithm with environment adaptive function,establishes the motion model and motor model according to the transmission structure of the window,deduces the relationship equation between several observation variables,and separates the clamping force as the basis of anti pinch judgment.In addition,the parameter self-learning mode is set in the program of the anti pinch control system.The system updates the friction parameters caused by environmental changes through self-learning,so as to achieve the environmental adaptive function of the anti pinch system.Finally,the window anti pinch control system designed in this paper is installed on the door,which communicates with the body controller through LIN bus,and its performance is tested and analyzed in different environments.According to the experimental results,the anti pinch control system has the advantages of high anti pinch precision and strong adaptability to the environment,and has good practical value.