Getting to Know Sensors, Sensory Organs of Cars

Getting to Know Sensors, Sensory Organs of Cars

Cars are equipped with numerous sensors. However, it is difficult to notice how many and where these sensors are installed unless you pay attention. This is because sensors are hidden in various places to avoid harming the design of the vehicle. If you look closely at the round button-like shape of the vehicle's frame (mainly the corner of the bumper), inside the grill, or behind the side mirror, you can find various sensors.

Today, we prepared a story about sensors for those of you who are curious about what functions these sensors exist for and how they work.

Sensors are the ‘eyes of the car’. Various sensors installed throughout the vehicle act as the eyes and ears of the vehicle to collect information, and based on this, the electronic control unit, the brain of the vehicle, recognizes and judges the situation and issues driving, braking, and steering control commands.

The core of ADAS (Advanced Driver Assistance System), which is completed through sensors, and autonomous driving functions ultimately lies in preventing accidents, protecting occupant safety, and reducing driver fatigue. In order to identify obstacles in blind spots that the driver is not aware of and to take preemptive measures by identifying unforeseen situations before the driver, it is important for the sensors installed in the vehicle to operate accurately and to make appropriate judgments based on the information collected by the sensors. 

Each sensor installed in the car works organically with each other to complete its function. For example, Automatic Emergency Braking (AEB), which prevents collisions with obstacles, can be configured based on the front radar and front camera. Cameras and radars detect obstacles and transmit information, and if the driver does not take action or brakes late even when approaching the collision risk distance, the autonomous driving integrated controller issues a braking command to prevent a collision or minimize damage.

In addition, the smart cruise control, which automatically provides acceleration and deceleration, operates with front radar, camera, and navigation, and the Highway Driving Assist system operates with radar (keeps distance between vehicles) and camera (keeps in lane), respectively. does.

As such, automotive sensors are an important core technology in developing ADAS and autonomous driving functions, and it is a field in which mobility companies are focusing their efforts to develop technology. HL Clemove, a company specializing in autonomous driving, holds more than 2,200 patents related to autonomous driving based on its independent technology, and based on this, it supplies more than 20 million ADAS parts to about 13 companies around the world.

The sensors most familiar to us are probably cameras, ultrasonic sensors, and GPS. These sensors are installed to assist the driver, such as collision detection and parking assistance, and to ensure the safety of passengers.

Cameras, as we are familiar with, identify nearby objects through the light entering the lens. Because it can identify the shape of surrounding objects in detail, it is also used to assist radar that has difficulty identifying individual objects. The development of autonomous driving technology that recognizes the driving environment using only a camera is actively underway. However, there are disadvantages that there are restrictions on shooting in dark or bad weather conditions, and it is difficult to function properly when the lens is covered by backlight or dust.

Ultrasonic sensors can be said to be the most well-known sensors among the sensors installed in automobiles. It is mounted on the front, rear, and side of the vehicle to detect collisions or is used for parking steering assistance systems. This ultrasonic sensor is used in the parking assistance system, which emits a ‘beep’ warning when an obstacle approaches when reversing. However, compared to other vehicle sensors, ultrasonic sensors have a relatively short measuring range and are highly affected by the environment. Therefore, in autonomous driving systems, it is used to develop functions such as low-speed driving in narrow roads such as alleys or automatic parking.

Radar (Radio Detection And Ranging) is a sensor that identifies objects through electromagnetic waves. You can find out information such as distance, direction, and speed from nearby objects through signals that emit electromagnetic waves and return. It can detect from short, medium, and long distances, and can perform well regardless of the surrounding environment, such as weather or time of day. For this reason, automotive radar is considered a key component for autonomous driving as well as ADAS functions such as automatic emergency braking (AEB) and smart cruise control.

HL Clemove has established a full lineup of radars covering short and long distances, enabling radars to be installed on the front, side (corner) and interior of vehicles to ensure the safety of passengers both inside and outside the vehicle.

However, since radar has a relatively low ability to identify the specific shape of an object, the high-resolution detection ability to accurately identify individual objects is an important competitive advantage of radar.

A sensor that can compensate for the disadvantages of these radars is LIDAR (Light Detection And Ranging), which uses light instead of electromagnetic waves. It sends out a high-powered pulse laser and analyzes the information that is reflected from the object and recognizes the surrounding information in 3D. It has the same basic principle as radar, but the biggest advantage is that it can precisely measure the position, angle, and distance of an object as well as its specific shape.

It's not easy to find a vehicle equipped with Lidar yet. Lidar is in the limelight as an autonomous driving sensor, but it is more expensive than radar, so the cost burden is high and its performance deteriorates in bad weather.

However, many companies are working to commercialize lidar, and self-driving vehicles equipped with lidar are being released one after another, so it is expected that mass-produced vehicles equipped with lidar will be encountered on the road soon.

So far, we have looked at the various sensors installed in automobiles and what roles they play. It can be seen that each sensor complements each other's weaknesses and maximizes its strengths, organically composing the vehicle's system.

Vehicle sensors are a shield for our comfortable and safe movement. If you knew there were sensors in your car, but you didn't know where they were located or what they were doing, why don't you take a look at the sensors installed in your car before getting into the car?