Automobile Rain Sensor Design And Automatic Wiper Control System

With the development of automobile industry, the sales volume ofautomobile is keeping a sustainable growth in our country. But it also causesserious traffic jams. Our country is a rainy country, so it will cost a lot of timedriving in rain. Although every car has a wiper, the majority of them arerequired to manually control. It will distract drivers and make driving difficultand cause traffic accidents. Therefore, this paper conducts the research for theautomobile wiper control system. It uses the reflective infrared rain sensor tocontrol the wiper to work and make it achieve auto control.In this paper, the main work is as follows:1) It designs and builds the whole hardware system and circuit of thereflective infrared rain sensor, including the selection of MCU, infraredemission circuit, receiving circuit, silicon photocell amplifier circuit,sampling circuit, a differential amplifier circuit, a negative feedback circuit,communication circuit and power circuit etc. It describes the workingprinciple of the device of the detecting rain. It extracts effective signal inintensive background noise by using sampling integral method. It introduces anegative feedback in the rain detection circuit to form a closed-loop system. Itcan make rain sensor adapt the automobile front windshield with differentthickness. At the same time it can eliminate the interference of scratches anddust.2) The core control algorithm for the automatic wiper control device is aneural network algorithm. The droplet size and frequency which are detectedby the reflective infrared rain sensor are two input value of neural network.And the wiper movement speed and movement frequency are the two outputvalue of neural network. In order to establish a complete automatic wipercontrol rules, it must determine the connection weights between each layer ofnetwork nodes by using empirical data to train neural network.The final simulation results show that the reflective infrared rain sensor designed in the paper can detect rain on the windshield effectively, and it cancontrol the wiper to work automatically.