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The monocular camera is located in front of the rearview mirror.
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ProPilot, an automatic driving technology developed by Nissan Motor Co Ltd, controls the steering, accelerator and brakes on a single lane of an expressway.

One of the characteristics of the ProPilot is that it uses only one monocular camera, lowering cost. The technology was employed for the Serena minivan to be released in late August 2016. Nissan plans to sell the Serena equipped with the technology at a price of ¥3 million (approx US$28,286) or lower.

Israel-based Mobileye NV developed the core technology that recognizes vehicles and pedestrians with a monocular camera. The ProPilot uses Mobileye's "EyeQ3" SoC (system on chip) designed for image recognition.

The EyeQ3 supports a camera pixel count of one million or more and has a detection range of 100m or more. This time, Nissan adopted a monocular camera whose horizontal and vertical angles of view are 52° and 40°, respectively.

Nissan also employed Mobileye's SoC for the automatic braking system that was first adopted for the X-Trail compact crossover SUV. However, the Soc is "EyeQ2," which is one generation older than the EyeQ3, and supports a pixel count of up to about 300,000, narrowing detection range and angle of view.

Nissan developed a technology to control a car based on the EyeQ3's recognition results. For example, it decided the timing of switching a preceding vehicle to follow when another vehicle is coming between the user's vehicle and the preceding vehicle.

From the initial stage of the development, Nissan was focusing on developing the ProPilot by using only a monocular camera. Many other companies that realized similar technologies used a milliwave radar device, etc in addition to a camera.

"When many sensors are used, they increase costs, making it difficult to spread the use of the system," the company said. "If it is not widely adopted, it is not possible to decrease the number of traffic accidents."

There is a limit in recognizing the surrounding environment only by using a camera. For example, it becomes difficult when there is a strong backlight or dense fog. In view of this, Nissan made efforts to develop a system for warning the driver when the surrounding environment cannot be accurately recognized by the camera and the system cannot continue to function.