What is the Principle of the Car Wiper Sensor?
2 Answers
Car wiper sensor principle: When the sensor detects rain falling on the windshield, it sends a command to the wiper to start working, thereby clearing the rainwater on the front windshield to ensure the driver's unobstructed vision. Additionally, it issues commands to automatically close the vehicle's electric windows and sunroof to prevent the interior from getting wet. The two widely used mainstream sensors are optical sensors and capacitive sensors. When the windshield becomes wet, the dielectric constant of the windshield changes differently depending on the amount of water in contact with it. Installing the sensor on the surface of the windshield or closely beneath its lower surface is beneficial for the sensor's operation, as this placement allows the sensor to achieve optimal sensitivity.
The principle of the rain sensor sounds pretty cool. I remember it mainly relies on a small sensor on the windshield. This thing is somewhat like an eye, capable of detecting changes in light; typically, it uses a combination of infrared light-emitting and receiving components installed on the inner side of the glass, scanning the outside. When it rains, raindrops falling on the glass scatter the light, and the sensor detects the reflection or changes in light intensity, then converts this information into an electrical signal sent to the car's computer system. Upon receiving the signal, the computer immediately decides whether to activate the wipers and adjust their speed, all based on algorithms that determine the amount of rainfall, eliminating the hassle of manual operation. I've seen this module during car repairs—it has a self-calibration feature to avoid misjudgments due to dust or light rain, which is quite smart. The principle is simple, but in practice, it requires considerations like optical interference prevention and waterproof design to ensure accurate activation of the wipers in complex driving conditions, enhancing driving convenience.
