What is the Principle of the Tire Pressure Monitoring System?
2 Answers
There are two principles of automotive tire pressure monitoring: 1. Direct Tire Pressure Monitoring: Direct tire pressure monitoring devices use pressure sensors installed in each tire to directly measure the tire's air pressure. A wireless transmitter sends the pressure information from inside the tire to a central receiver module, which then displays the data for each tire's pressure. When the tire pressure is too low or there is a leak, the system automatically alerts the driver. 2. Indirect Tire Pressure Monitoring: Indirect tire pressure monitoring works by detecting when the air pressure in a tire decreases, causing the vehicle's weight to make that tire's rolling radius smaller, which in turn makes it rotate faster than the other wheels. By comparing the differences in rotational speed between the tires, the system monitors the tire pressure. Indirect tire pressure alert systems essentially rely on calculating the tire's rolling radius to monitor air pressure.
The Tire Pressure Monitoring System, abbreviated as TPMS, primarily relies on sensors to monitor tire pressure. Modern vehicles mostly use direct TPMS, where a small sensor is installed on each wheel to measure air pressure and temperature in real-time and wirelessly transmit the data to the vehicle's onboard computer. If the pressure drops, the computer illuminates a warning light on the dashboard to alert you. Another type, indirect TPMS, doesn't use sensors but relies on the ABS system: when a tire loses air, its diameter decreases, causing it to rotate slightly faster; the system detects this by comparing wheel speed differences to infer issues. This system is crucial as it helps prevent tire blowouts and enhances driving safety. Many vehicles come with it as standard equipment, making daily driving more worry-free by allowing timely action when pressure is low, thus avoiding excessive tire wear or increased fuel consumption.
