Comparison of the advantages and disadvantages of the three main sensors for vehicle forward-anti-collision--samaeye
Public Time: 2018-06-05 11:50:23
What are the advantages and disadvantages of the three main mainstream sensing technologies: camera collision prevention, laser radar collision avoidance and millimeter wave radar collision avoidance system.
ADAS camera collision warning system
Camera image sensor (image processing, visual recognition) can obtain environment scene information, is the application of machine vision in vehicles, is the second largest source of environmental information for vehicles. In lane deviation, pedestrian identification, speed limit sign recognition has its own unique.
Advantages of ADAS camera collision warning system:
1. High resolution, accurate identification of obstacles, can capture the shape and details of objects, good at the complex driving environment analysis and processing;
2. It can recognize lane line (realizing lane deviation warning), stable performance and practical application verification;
3. the production cost is suitable for popularization and popularization ;is economical , practical , low in cost and complete in function ;
4. Identify traffic signs (speed limit signs; pedestrian detection).
ADAS camera collision warning system shortcomings:
1. Light needs to be replenished at night;
2. The horizon of rain and fog is shortened.
Lidar system
1. Multi-line lidar (the current lidar used for on-board testing can achieve 64 lines) multi-line (also called multi-layer, three-dimensional) lidar can obtain three-dimensional dimension information of environmental space. The target recognition of laser radar sensor depends on the number of scanning laser wire harness. It scans the environment in 2D or 3D through multi-wire harness, and determines the distance of object by the laser reflected from object. The more information the target is collected within a certain period of time. Lidar will be affected by dust, rain and fog weather, usually in cars multi-line lidar will be combined with other sensors to achieve obstacle avoidance.
The advantages of single line lidar are:
1) 360 degree scanning;
2) ranging sensitive 2D imaging with high accuracy and recognition of object shape;
3) wide coverage; long range; night work.
The disadvantages of single line lidar are:
1) large product specification;
2) the cost of 3D scanning lidar is high, and the longer the distance is, the higher the cost is.
3) can not detect the lane line; can not identify the traffic signs; affected by rain, snow, smog, dust and so on.
2. Single line lidar
The single line laser radar detects by emitting laser beams and returns the measured values expressed by polar coordinates according to the relative position of each point in the region with the scanner, that is, the distance and relative angle between the object and the scanning center of the scanner.
The detection range is very limited, only for ranging, generally not for environment sensing alone, or only for specific environmental situations. Single line lidar can not be used independently for vehicle front collision prevention. In our country, a small number of merchants use single line laser to realize AEBS, which has a great security hazard.
Advantages of single-line lidar:
1) low cost, sensitive ranging;
2) long detection range; night work.
The disadvantages of single-line lidar include:
1) large product specification;
2) higher cost of ranging with limited detection distance;
3) greater risk of blind area with narrow detection range;
4) poor anti-jamming ability, high false alarm rate, and only linear detection. Light beam can not be used normally after blocking, affected by rain, snow, smog, dust, and other bad weather, such as rain and snow smog, sandstorm and other bad weather can not be turned on;
5) can not detect the lane line; can not identify the traffic signs.
77GHz millimeter-wave radar
The millimeter wave radar sensor is a radar whose operating frequency is chosen in the frequency domain of 30-300 GHz (wavelength is 1-10 mm, that is, millimeter wave band). The 77GHz millimeter-wave radar has excellent advantages in multi-target detection, ranging and obstacle recognition.
1. The detection distance is 150-200 meters;
2. Strong anti-interference ability, strong ability to penetrate the clouds and fog, not affected by rain and smog weather, day and night, all weather stable work.
3. Strong anti-scintillation ability, sensitive speed measurement, accurate target recognition and high accuracy.
4. Small size, light weight, good concealment. The cost is moderate.
The disadvantages of 77GHz millimeter wave radar :
1 . Camera sensor auxiliary work is required for special environment ;
2 . Unable to identify traffic sign ;
3 . Recognition of fine objects is poor .
