Application of Ultrasonic Radar in Automobiles Analysis of Main Vision Sensors in ADAS Systems

According to estimates, the market size of ultrasonic radar will reach RMB 4.2 billion, RMB 8.7 billion and RMB 19.2 billion in 2019, 2020 and 2025 respectively, with a compound growth rate of about 38% from 2016 to 2025.

4. Camera: ADAS system main visual sensor

The vehicle camera is the main visual sensor of the ADAS system and one of the most mature vehicle sensors. After the lens captures the image, the photosensitive component circuit and control component in the camera process the image and convert it into a digital signal that can be processed by the computer, thereby realizing the perception of the road conditions around the vehicle. The camera is mainly used in ADAS functions such as 360 panoramic imaging, forward collision warning, lane departure warning and pedestrian detection.

ADAS system is equipped with more than 6 cameras. The installation position of the camera varies according to the needs of different ADAS functions. It is mainly divided into front view, rear view, side view and built-in. When realizing automatic driving, the full set of ADAS functions will install more than 6 cameras. The unit price of the front view camera is about 1,500 yuan due to the need for complex algorithms and chips, and the unit price of the rear view, side view and built-in cameras is about 200 yuan. The popular application of ADAS has brought huge market space for vehicle-mounted camera sensors.

▲Camera installation location and features

In the short term, monocular cameras will be the mainstream technology route. The forward-looking camera ADAS system can be divided into two technical routes: equipped with a monocular camera and equipped with a binocular camera. Compared with monocular cameras, binocular cameras have more powerful functions and more accurate measurements, but the cost is relatively high, so they are mostly installed in high-end cars. Due to the constraints of comprehensive factors such as cost, manufacturing process, reliability, and accuracy, the binocular camera solution is difficult to promote in the market. The low-cost and reliable solution of the monocular camera, combined with other sensors, can fully meet the functions of L1, L2, and some L3 scenarios. Therefore, in the current market environment, the monocular camera solution will still be the mainstream.

Cameras are mainly used as auxiliary sensors for radar. Although cameras have high resolution and can detect the texture and color of objects, their visual effects are poor in backlighting or complex light and shadow conditions, and they are easily affected by bad weather. Therefore, the image information obtained by cameras will be mainly used in a few areas such as traffic sign recognition, as a supplement to lidar and millimeter-wave radar.

The camera industry chain can be roughly divided into three parts: upstream component production, midstream module packaging and integration, and downstream product application.

1) Upstream components mainly include CMOS sensors, lens groups, DSP, etc. CMOS sensors and DSP in the upstream market are mainly monopolized by foreign companies such as Sony, Samsung, TI, and ON Semiconductor. Domestic companies have advantages in lens group production, among which independent brands such as Sunny Optical have high competitiveness;

2) Midstream packaging integration includes module packaging and system integration. The module packaging and integration process is complex, and the market is monopolized by foreign companies. The main manufacturers include Panasonic, Sony, Valeo and other companies.

3) Downstream products are used in vehicle manufacturers and 4S stores.

The automotive camera industry has high requirements for manufacturing processes and a long certification cycle. Compared with mobile phone cameras, automotive cameras face more severe working conditions and need to meet multiple requirements such as high temperature resistance, shock resistance, anti-magnetic, and stability. In particular, the front-view cameras used in ADAS systems involve driving safety and must have very high reliability requirements, so the manufacturing process requirements for automotive cameras are very high. Before becoming a first-tier supplier to a vehicle manufacturer, a company needs to undergo a large number of different types of rigorous tests. Once it enters the supply system of a vehicle manufacturer, it will form a very high barrier, making it difficult to be replaced and the replacement cost is also very high. For example, it took Mobileye, a leading foreign visual sensor company, 8 years to enter the original equipment market from research and development.

According to estimates, the camera sensor market size is expected to reach 15 billion yuan in 2019, entering the L3 stage. The market size can reach 20.5 billion yuan and 31.5 billion yuan in 2020 and 2025, and the compound growth rate from 2016 to 2025 will reach about 17%.

04

Multi-sensor fusion is an inevitable trend

ADAS integrates a variety of sensors to drive the development of the sensor market. With the increase in the proportion of smart cars in the future, the ADAS market will accelerate its growth. According to research by Goldman Sachs Global Investment Research, the current global ADAS penetration rate is generally not high, with penetration rates in Europe, the United States and Japan only 8%-12%. According to calculations by Gasgoo Automotive Research Institute, the penetration rate of ADAS in my country is around 2%-5%; judging from the life cycle, ADAS has achieved a leap from the introduction period to the growth period. Overall, under the wave of smart driving and unmanned driving, the level of automotive electronics and intelligence continues to improve, and ADAS has a lot of room for growth. Environmental perception is the hardware foundation of ADAS, and the application of sensors is indispensable. The increase in ADAS penetration will lead to a substantial increase in the demand for vehicle-mounted sensors, and the market size of sensors will further expand in the future.

▲ADAS integrates multiple sensors

Environmental perception sensors are the eyes of cars, and millimeter-wave radars have outstanding comprehensive advantages. In the context of the intelligent era, environmental perception is particularly important. Different sensors have different principles and functions, and they play their own advantages in different scenarios, making it difficult for them to replace each other. Millimeter-wave radars have outstanding comprehensive advantages and are expected to become the main sensor for ADAS systems.

▲Comparison of the advantages and disadvantages of various sensors

▲Millimeter wave radar has outstanding comprehensive advantages

Single sensor has outstanding characteristics and cannot form complete information coverage. Multi-sensor fusion is an inevitable trend of future development. It also provides necessary technical reserves for the realization of Level 3-Level 5 autonomous driving solutions. At present, there are two main technical routes for autonomous driving environment perception: one is the multi-sensor fusion solution dominated by vision represented by Tesla, and the other is dominated by low-cost lidar, with typical representatives such as Google Waymo. Foreign mainstream car companies such as Tesla, Audi, and General Motors have released their multi-sensor plans for autonomous driving cars. Multi-sensor fusion is crucial to ensure the vehicle's global positioning and understanding of the surrounding environment.

In general, the sensors used by ADAS mainly include cameras, radars, lasers, and ultrasonic waves, which can detect light, heat, pressure, or other variables used to monitor the status of the vehicle. They are usually located in the front and rear bumpers, side mirrors, inside the steering column, or on the windshield of the vehicle. When each subsystem in ADAS is in operation, it is inseparable from the collection, processing, and judgment of information, and after the judgment is completed, the system gives instructions to the vehicle body to make the car perform different actions. In such a process, sensors such as radars and cameras, as well as processors such as MCUs or image processing ICs, have become the most important components used. On the road to L5 level autonomous driving, the maturity and perfection of the ADAS system is the basic guarantee.