Most advanced driver assistance systems (ADAS) now have impressive features, including:
- Automatic emergency braking.
- Parking assistance.
- Blind spot monitoring.
- Forward collision warnings.
- Adaptive cruise control.
- Traffic sign recognition.
- Lane detection and lane departure warnings.
These systems are capable of offering so many advanced safety features largely because they rely on multiple types of ADAS sensors, each of which has their own unique strengths and vulnerabilities and complement each other.
In this post, we’ll discuss the four key types of ADAS sensors mechanics and repair shops need to be familiar with, including the pros and cons of each, which features they support, and essential ADAS calibration needs.
Camera sensors
ADAS camera sensors use video and image sensors to detect objects and provide drivers with real-time images. These sensors are often used for ADAS features like parking assistance, collision avoidance, and lane departure warnings.
When it comes to different types of sensors in cars, camera sensors currently produce the most high resolution images and are highly effective at detecting 2D shapes and colors accurately. It’s important to note, however, that camera sensors may have reduced performance in poor weather or lighting conditions.
LiDAR sensors
LiDAR sensors send out laser pulses, which bounce off surrounding objects, and then measure how long it takes for those pulses to return. This allows the sensors to calculate precise distances between a driver’s vehicle and other objects.
LiDAR sensor technology is currently some of the most advanced out of ADAS sensors. It offers strong potential in supporting autonomous driving features, and currently supports ADAS features like object detection and avoidance, adaptive cruise control, blind spot detection, and lane detection.
These sensors are capable of creating high resolution detection even at a far range, and has outstanding 3D mapping capabilities.
Sonar sensors
Sonar sensors use sound waves for object detection, emitting sound waves and determining how long it takes for the sound to return. They’re most effective at detecting objects at close range, and are helpful for object detection even in tight spots; they aren’t as effective for object detection at a far range.
As a result, these sensors are typically used for features like backup detection and parking assistance.
Radar sensors
Radar sensors use radio waves to detect an object’s distance and location. They can be used to help assess another vehicle’s speed, supporting features like adaptive cruise control, forward collision warnings, lane departure warnings, and automatic braking.
These sensors function well regardless of weather or light conditions, though they may have more difficulty detecting objects effectively at a far range.
Radar vs sonar vs LiDAR sensors
Radar, sonar, and LiDAR sensors all work similarly: They emit radio, sound, or light waves respectively and assess how long it takes for the sound to return back. They’re all used for object detection, but they each have their own pros and cons that complement each other.
Radar sensors and sonar sensors, for example, function well regardless of weather or light conditions. LiDAR sensors perform well in all light conditions, but performance can be impacted by inclement weather like falling rain or snow.
LiDAR sensors, however, can deliver the highest resolution at range, resulting in accurate object detection, modeling, and 3D mapping, even at far range. Radar sensors and sonar sensors both may have difficulty accurately identifying some objects at far ranges, and sonar in particular is most useful for close object detection.
Sonar’s biggest advantages are its ability to strongly and accurately detect objects closeby, including in tight spaces, and to be low cost to produce and install. LiDAR in particular is much more expensive, though future developments may aim to reduce overall costs.
Radar sensors Function, Pros, and Cons
Function: Use radio waves to detect distance and object location
Pros: Strong performance despite weather or light conditions
Cons: Difficulty accurately identifying some objects at far range
LiDAR sensors Function, Pros, and Cons
Function: Uses light from a laser to calculate object distance
Pros: High resolution at range resulting in accurate object detection and modeling. Excellent 3D mapping
Cons: Potentially impacted performance in inclement weather, like active rain or snow fall
Sonar sensors Function, Pros, and Cons
Function: Uses sound waves for object detection
Pros: Low cost. Strong ability to detect close objects even in tight spaces
Cons: Short detection ranges. Potential difficulty accurately detecting small or soft objects
Calibration needs for ADAS sensors
ADAS sensors are highly effective at improving driver and passenger safety— but only when they’re calibrated correctly. If sensors aren’t calibrated correctly, they may produce inaccurate assessments that could result in ADAS actions that happen too early, too late, or not at all.
All ADAS sensors are highly sensitive and may need to be recalibrated after the following events:
- Motor vehicle accidents, even minor fender benders.
- Structural repairs to the vehicle.
- Sensor removal or replacement.
- Removal of bumpers or grilles.
- Airbag deployment.
- Changes or repairs to the vehicle’s level at the front or rear axle.
- Suspension repairs.
- Wheel alignment.
- Windshield replacement.
- Driver reports of inaccurate ADAS functioning.
Depending on the impacted sensors and the vehicle in question, mechanics may need to perform static or dynamic calibrations.
Static calibrations are performed on a stationary vehicle to assess sensor angles in a controlled environment. You must have a level floor, no reflective surfaces, and uniform lighting for accurate calibrations.
Dynamic calibrations, which are often performed second, must be performed while driving to ensure that the ADAS system correctly interprets real-world data. These calibrations should only be conducted with strong road visibility and in clear weather conditions, and may require clear road markings, certain speeds, or objects for detection.
ADAS Sensors and Calibrations
ADAS technology is evolving quickly, and it’s becoming much more common. Many car manufacturers are offering more safety features for lower-level trims, and some ADAS features like automatic braking are expected to be standard by the end of this year.
As a result, more customers will come to their mechanic needing ADAS calibrations. Revv can help.
Many mechanics have historically shied away from ADAS calibrations, as each vehicle and manufacturer is unique. This is leaving money on the table, however, and prevents these shops from offering essential services to clients.
Revv can help. Our AI-powered software can help you quickly identify which sensors need calibrations, what calibrations are needed, and provide the necessary OEM documentation to make all needed repairs for each individual VIN. You can provide improved support for each customer, and ensure that you’re identifying every potentially billable repair.
Save up to two hours for each calibration and earn more revenue. Book your demo to see how here.
