Does a Parking Sensor Use Ultrasonic or Electromagnetic Waves?
2 Answers
The principle of parking sensors is based on ultrasonic waves. Below is a detailed explanation of how parking sensors work: 1. The anti-collision alarm system used during car reversing, commonly known as parking sensors, operates on ultrasonic technology. 2. When the car is in reverse gear, the reversing gear shift device automatically activates the power supply of the ultrasonic parking sensor system, which then resets and enters the working state. 3. A pulse voltage is applied to the ultrasonic transmission and echo reception circuit through a four-to-one analog switch. 4. The emitted ultrasonic waves form reflected waves upon hitting an obstacle, with some of these reflected waves returning to act on the ultrasonic sensor. 5. Through the acoustic/electrical conversion of the ultrasonic sensor, the waves are transformed into weak electrical signals. 6. The system immediately responds to the interrupt and executes the external interrupt service routine.
I've always been interested in automotive technical details. The reversing radar uses ultrasonic waves, which are high-frequency sound waves, rather than electromagnetic waves. Ultrasonic sensors are installed on the rear bumper of the car, emitting sound pulses that reflect back when they hit an obstacle. The distance is calculated based on the time difference, and an audible alert or warning display is triggered. Ultrasonic waves are chosen for this purpose because they are highly accurate for short-distance detection, cost-effective, and easy to install, making them ideal for reversing scenarios. In contrast, electromagnetic waves like radar are used for long-distance applications, such as adaptive cruise control, where the equipment is more complex and expensive. Reversing radars typically detect objects within a few meters, and ultrasonic waves offer good interference resistance and fast response. However, rain or dirt covering the sensors may affect performance, but regular cleaning can resolve this. After years of development, ultrasonic technology in reversing radars has proven mature and reliable, helping countless drivers avoid minor collisions.
