Is the car speedometer displaying average speed or instantaneous speed?
2 Answers
It displays instantaneous speed. Below is a detailed introduction to the vehicle speed sensor: 1. Working principle: The vehicle speed sensor consists of a permanent magnet, magnetic poles, coil, and gear ring. When the gear ring rotates in the magnetic field, the gap between the gear ring teeth and the electrode changes at a constant speed, causing the magnetic reluctance in the magnetic circuit to vary. The magnetic flux periodically increases and decreases, generating an induced voltage at both ends of the sensor coil that is proportional to the rate of change of the magnetic flux. This AC voltage signal is directly transmitted to the vehicle's control computer to ensure stable performance. 2. Installation location: It is generally installed inside the drive axle housing or transmission housing, with the sensor signal wire housed in a shielded casing.
After driving for so many years, I've realized that the speedometer displays instantaneous speed, not average speed. Every time you press the accelerator or brake, the needle or digits jump immediately, reflecting the vehicle's current speed. This relies entirely on sensors on the wheels that measure tire rotation in real-time, which the computer then converts into speed. In contrast, average speed is calculated by dividing total distance by driving time, something navigation apps show only at the end of a trip. The importance of the speedometer lies in its ability to instantly warn you if you're speeding, helping to prevent accidents. I remember once on the highway, the gauge suddenly showed 100 mph, prompting me to ease off the accelerator. It's also important to pay attention to the sensors during regular maintenance to prevent inaccurate readings.
