车辆雨刷自动控制系统中相邻电容传感器设计

Proximity Capacitive Sensor Design in an Automatic Car Wiper Control System

提出一种应用于车辆雨刷自动控制系统的新型相邻电容传感器设计方案,能够在节省成本的同时达到高灵敏度和高鲁棒性。对已有的光电传感器技术,压电传感器技术与电容传感器技术分别进行分析比较。设计三种相邻电容传感器,通过在等参数同测量环境下,利用有限元剖分法对三种相邻电容传感器分别进行的电场分布仿真,并使用阻抗分析仪对测量边缘电容进行比较,确定最优设计。对最优传感器进行测量噪声分析,并提出解决办法。试验结果表明,花形电容传感器性能最佳且相邻电容传感器能够取代光电,压电传感器应用于车辆雨刷自动控制系统中。

A new design scheme of proximity capacitive sensor used for automatic car wiper control system is presented. It aims to develop a low-cost sensor with high sensitivity and robustness. The principles of sensing technique based on optical, piezoelectric and capacitive sensors are introduced respectively. Three types of proximity capacitive sensors are designed, and their performances are simulated by using COMSOL and Matlab under the same conditions. The key parameters of the sensor design are discussed and determined. An impedance analyzer is used to measure the fringe capacitance between each electrodes pair. At the last, the system noise occurring in measurement is discussed and the solving method is given. The experimental results indicate the validity and importance of the capacitance-based sensing technique which can be used in an automatic car wiper control system.