How Does a Dash Cam Work?
2 Answers
An automotive dash cam is similar to the "black box" used in aircraft. Its working principle involves digitally recording and cyclically updating the road conditions in front of or around the vehicle. It can even record data such as in-car audio, vehicle acceleration, steering, and braking, which can be used to investigate traffic accident liability. Main functions: Protecting drivers' legal rights: In case of collisions with pedestrians crossing the road or cyclists/motorcyclists, drivers may face extortion attempts. A dash cam can provide valid evidence for the driver. Playback of surveillance footage: Accident liability becomes clear at a glance, enabling traffic police to handle accidents quickly and accurately. This allows for rapid scene clearance to restore traffic flow while preserving crucial evidence of the incident, contributing to a safer and smoother traffic environment.
I really enjoy studying automotive electronics, and the principle of dash cams is quite fascinating. It's like a small camera mounted on the windshield, capturing the view ahead through its lens and transmitting it to a sensor that converts it into digital signals. The processor then compresses the video—for example, using H.264 format to reduce file size—and stores it in real-time onto an SD card. Here’s the key: recording operates in a loop mode, continuously overwriting old footage. However, the built-in G-sensor detects collisions or sudden braking and automatically locks that segment to prevent overwriting. This ensures critical evidence is preserved in case of an accident. Some high-end models even include GPS to log location and speed, adding an extra layer of safety. Installation is simple—just plug into the cigarette lighter for power—but choosing a higher-quality model with better resolution ensures clear details even at night. Regular maintenance, like periodically cleaning the SD card, can extend its lifespan.
