A dashcam G-sensor is an essential safety feature that helps lock and protect video footage when sudden impacts or collisions are detected. Most dash cameras come equipped with this function to ensure real-time video recording is preserved after a crash, preventing it from being overwritten.

What Is a G-Sensor?

A G-sensor is a gravity sensor that detects changes in acceleration force. This force occurs during acceleration processes, such as swaying, falling, rising, or other types of movement. These changes are transformed into electrical signals by the G-sensor, and through microprocessor calculation and analysis, various programmed functions can be performed.

For example:

• MP3 players can change tracks based on the user’s shaking direction.
• Lenovo ThinkPad series notebooks have a built-in G-sensor that protects the hard drive when sudden acceleration (e.g., falling) is detected.

The G-sensor is an intelligent system used to detect the current state of the hard disk. During an accidental fall, the hard disk senses acceleration, and the magnetic head automatically returns to its original position, separating from the disk to prevent damage during read/write operations.

Today, many industries utilize G-sensor technology, including dash cameras, mobile phones, and security systems.

What Does the G-Sensor Do for a Dashcam?

The gravity sensing function in a dash camera is also known as the gravity sensing image recording protection system. It records gravity-sensing information and evaluates environmental offset — up/down, left/right, and front/rear.

When the dashcam is connected to the vehicle and a collision causes vibration, the G-sensor triggers the camera to automatically lock the video. This ensures the video will not be overwritten and preserves important evidence.

What Is the Working Principle of Gravity Sensing?

To enable gravity sensing, the dashcam must contain a built-in G-sensor chip and related components. The system generally includes:

• Three sensors
• A processor
• A controller

In this setup:

• The G-sensor detects acceleration and environmental changes.
• The processor analyzes the data.
• If acceleration exceeds a threshold, the controller commands video protection or triggers an alarm.

This process completes in under 200 milliseconds. Once normal acceleration resumes, the dashcam continues regular operation.

Example:

In a collision, movement like shaking or falling is converted into electric signals by the sensor. The processor analyzes the acceleration and records video from both before and after the incident. The protected file remains safe from automatic deletion or overwriting.

What Is the Role of the G-Sensor in a Dashcam?

The G-sensor records vehicle movement along the XYZ axes:

• X-axis: Left and right changes during acceleration
• Y-axis: Front and back changes
• Z-axis: Up and down changes

Knowing the collision direction, the dashcam can forcibly record the 10 seconds before and 20 seconds after the impact, preserving the entire event. This video cannot be overwritten and serves as vital evidence.

High-quality dash cameras should include gravity sensing for:

• A better user experience
• Accurate emergency recording
• Real-time restoration of accident scenes

Upon sensing emergency braking or a crash, the dashcam records and saves the key video segments automatically — protecting them from loop overwrite. This recreates the accident scene and clarifies responsibility.

Conclusion

The gravity sensing function is essential for recording unexpected events and restoring the first scene of an incident. When buying a dashcam, ensure it has gravity sensing.

As a professional driving recorder manufacturer, Jimi IoT has over 15 years of experience and offers multiple dash camera models with G-sensors.
📩 For more information, contact us at info@jimiiot.com.