Around View Monitor (AVM)

The Around View Monitor (AVM), also known as a 360-degree surround-view camera system, is a parking assistance technology that uses ultra-wide-angle cameras mounted around the vehicle's exterior to capture real-time surroundings. These feeds are stitched together via computer vision algorithms to generate a seamless 360-degree top-down bird's-eye view, helping drivers eliminate blind spots. Serving as an evolution of the conventional reverse camera, AVM offers a cost-effective solution for full situational awareness.

Operating Principle

At the core of the AVM system are multi-camera coordination and real-time image stitching.

Hardware Setup: The system typically comprises four (or more) ultra-wide-angle fisheye cameras mounted on the front grille, beneath the wing mirrors, and near the rear number plate light, ensuring complete coverage around the vehicle's perimeter.

Image Stitching Process: Once each camera captures wide-angle footage of its respective sector, the image processor sequentially executes: distortion correction (rectifying the fisheye "barrel distortion" into a natural perspective), perspective transformation (projecting side angles into an overhead top-down view), and seamless stitching (merging the four video feeds via image fusion algorithms into a unified 360-degree bird's-eye view). Technical literature notes that precise multi-camera calibration and depth synthesis algorithms ensure a natural, artefact-free panoramic image.

Core Functions

2D/3D Perspective Switching: Basic AVM setups display a 2D top-down view, whereas advanced systems offer interactive 3D rendering, allowing drivers to pan and rotate the virtual camera angle via the touchscreen to check clearances around obstacles.

Dynamic Guiding Trajectories: As the driver turns the steering wheel, the on-screen dynamic parking guidelines curve in real time to show the projected reversing path, helping the driver judge steering inputs accurately.

Narrow Passage Assist and Moving-Off Blind Spot View: When navigating tight alleys, width-restricted gaps, or moving out of a parking bay, AVM can be manually engaged to check wheel-to-kerb clearance or verify that no low-lying hazards, such as children crouching near the front quarters, are present.

Extended Features

Transparent Chassis (Underfloor View): By buffering historical camera footage as the vehicle moves forward, the system renders a visual "see-through" effect of the underbody on the infotainment display. While helpful for inspecting road surface conditions and low obstacles, it is a digitally reconstructed image rather than real-time X-ray vision.

Turn Indicator Auto-Activation: When engaging the signal indicator to make a turn or when closing in on obstacles at low speeds, certain models will automatically project a magnified side-view feed on the centre screen.

Industry Landscape and Limitations

AVM is rapidly transitioning from a premium optional extra into standard equipment across mainstream models. Key Tier-1 suppliers include Valeo, Bosch, and HiRain Technologies, with their OEM solutions widely adopted by brands such as SAIC, GAC, BYD, and Geely.

System Limitations:

• Optical Distortion and Blind Spots: Minor distortion remains along the stitched seams of fisheye lenses. Furthermore, low-lying obstacles situated below the camera's direct line of sight and close to the bodywork (such as short bollards, low kerbs, or small pets) may not be detected and could "disappear" from the display.

• Dependence on Lighting and Lens Cleanliness: Display clarity drops significantly in poor lighting conditions at night or when camera lenses are obscured by dirt, rainwater, and road grime.

• Auxiliary Driver Aid Only: AVM is purely a parking assist feature; discrepancies may exist between on-screen distances and actual physical clearances. Drivers must always cross-check their surroundings using the side mirrors and rear-view mirror, retaining full responsibility for driving safety.