New cars come outfitted with advanced driver assistance systems (ADAS). These advanced safety systems use sensors to gather information about vehicle surroundings. Sensors collect data that provides safety warnings. ADAS can even use sensor data to know when to take temporary control over a vehicle’s braking or steering, all in the name of driver safety. As with all sensors, vehicle ADAS sensors are only as accurate as they are calibrated to be. Enter ADAS calibration, a fast-growing need in the automotive industry.
In this article, we will define ADAS calibration, provide an in-depth rundown on the subject, and give four common examples of sensors that need it.
ADAS calibration (and recalibration) is the precise physical alignment, testing, and electronic aiming of sensors that collect data to inform your vehicle’s advanced driver assistance systems (ADAS), like forward collision warning (FCW), lane departure warning (LDW), automatic emergency braking (AEB), and several others.
Recalibration tells sensors where to look. It also shows sensors their position in relation to the vehicle. Most ADAS sensors require precise aiming. As AAA explains, “… a sensor on the car that is out of alignment by a fraction of an inch or even one degree will be aimed at an area significantly off axis 50 or more feet down the road.” Likewise, according to IIHS Advisory 43, a change as little as .6 degrees would cut the reaction time of AEB in half.
In a brand new vehicle, ADAS sensors are professionally set in their factory standard positions. All sensors point in the same, precise place. But, throughout a vehicle’s life, things happen that cause sensors to come out of alignment — collisions, minor fender benders, and adjacent repairs or parts replacement. For example, vehicles with a windshield-mounted forward ADAS camera will require calibration after windshield replacement.
Unfortunately, ADAS sensors don’t all have self-diagnostic capabilities to tell the driver when they are out of calibration. Automotive professionals need to know and follow OEM standards regarding ADAS calibration, so that a vehicle’s ADAS systems properly function.
Types of ADAS Calibration
ADAS-equipped vehicles require static calibration, dynamic calibration, or both — it depends on a vehicle’s ADAS systems and OEM recommendations.
Static ADAS Calibration
The majority of vehicles start with static calibration. Static ADAS calibration takes place in a controlled environment while the car is stationary. ADAS static calibration uses special tools in a specially rendered environment to precisely set sensor angles. For proper static calibration, technicians need:
- Minimum of a 30’ x 50’ open space
- A leveled/finished floor
- Uniform, neutral color on walls and floor
- Uniform and adjustable lighting
- Unobstructed space around the vehicle
- No reflective surfaces
- No reflections on the windshield
- No direct sunlight
Static ADAS Calibration Equipment
Several pieces of calibration equipment are also needed to perform ADAS static calibrations, including the following:
- An ADAS scan tool — most OEMs require a diagnostic tool to access and initiate electronic scan and calibration procedures.
- An alignment rack — while all static ADAS calibrations require a flat, level surface, some OEMs go above, requiring the use of an alignment rack.
- ADAS calibration tool — tool requirements vary by OEM, but they all have the purpose of holding up targets a precise, calculated, and measured distance from the vehicle, and are able to stay in place and hold targets in place.
- Aiming targets — Some vehicles use one target, while others use multiple targets. Many targets look like enlarged black and white patterns, while radar aiming targets can be metal pyramid shapes, reflective metal plates, or an electronic Doppler box.
- Measuring tapes — or laser measuring devices are a must. Precise measurements are taken from the ADAS tool to the targets and more.
Note: Depending on a vehicle’s age, make, and model, some static calibration procedures for forward-facing sensors will require manual adjustments. However, final adjustments occur during calibration and will be performed by the ADAS module itself, electronically.
Dynamic ADAS Calibration
Some vehicles require just a dynamic calibration. On the other hand, many require static calibration and include dynamic calibration as the final step in the ADAS calibration process. Dynamic calibration requires driving the vehicle at certain speeds and conditions, while connected to an ADAS scan tool — but it’s far from a test drive. While the dynamic calibration process varies by OEM, specific parameters are needed. Examples include driving on clearly marked roads, following one or more vehicles, avoiding curved roads, and driving at designated speeds.
Note: Dynamic calibration may require two technicians. One ADAS tech safely drives the vehicle while the other operates the scan tool.
4 Examples of ADAS Sensors to Calibrate
Modern vehicles include a variety of ADAS sensors, though not all of them need calibration. To help understand, here are some of the most prevalent ADAS sensors that most often need calibration.
Steering angle sensors are pretty self-explanatory. They tell what direction the steering wheel is being turned. Setting your steering angle sensor is key to getting an accurate zero-point calibration. Some systems self-calibrate, some require re-calibration using a scan tool, and some require additional procedures. Typical calibration requirements include setting the wheels straight forward and using a scan tool to zero out the steering angle.
ADAS systems that use input from steering angle sensors:
- Adaptive headlights (Curve-adaptive headlights)
- Blind spot detection
- Lane departure warning (LDW)
- Lane keeping assist (LKA)
Calibration of steering angle sensors is typically needed after:
- Wheel alignment
- Steering/suspension repair
- Structural repair
- Airbag deployment
Mostly found mounted to the inside of a car’s windshield, near the rearview mirror, front-facing ADAS cameras detect cars, pedestrians, and obstructions in your vehicle’s forward view. Most OEMs use one forward-facing camera, while others, like Subaru, use two for better depth perception. Front-facing camera sensors gauge distance to forward objects, detect and watch lane markings, identify traffic signs (though some systems use a dedicated camera), and sense light levels.
ADAS systems that often use data from front-facing camera sensors include:
- Adaptive cruise control (ACC)
- Automatic emergency braking (AEB)
- Automatic high beams
- Lane departure warning (LDW)
- Lane keeping assist
Calibration of front-facing camera sensors is needed after:
- Airbag deployment
- Windshield replacement
- Vehicle alignment
- Change in suspension
- Many collision repair events, especially repair work involving more than cosmetic panel distortion
Forward Radar Sensors
Forward radar sensors are often located in a vehicle’s front bumper or grille. These sensors monitor the distance to forward objects and control the following distance. Some vehicles have a front radar system, some use cameras, and some use both, offering a system with an additional check and balance.
Calibration of forward radar sensors can be static, dynamic, or both. Static calibration includes aiming at metal reflector sheets or metal pyramid-shaped targets. It also requires a shop free of other reflective surfaces.
ADAS systems that often use forward radar sensor data:
Forward ADAS radar calibration is needed after certain circumstances:
- Removal of the front bumper or grille
- Front end structural repairs
Rear Radar Sensors
Located in a vehicle’s rear corners, behind the bumper cover, rear radar sensors, also need calibration. These shorter-range sensors are able to monitor the distance to approaching objects from the vehicle’s rear and sides.
Just like forward radars, the calibration of rear ADAS radar sensors is static, dynamic, or both. Depending on the OEM model, and model year, there are many different procedures for calibrating rear radar sensors, all requiring a software tool, measuring devices, and other equipment. To perform static calibration, a calibration mat, corner reflector, or laser tool may be needed.
ADAS systems that use rear radar sensors:
- Blind spot warning (BSW)
- Rear cross traffic alert (RCTA)
- Rear automatic emergency braking (Rear AEB)
Rear radar sensors need calibration when:
- Sensor or sensor bracket is replaced
- Damage to mounting locations
- Rear bumper removed or replaced
- Structural body repairs at the rear of the vehicle
1. ADAS calibration is vehicle-specific. Each make and model requires different OEM calibration preparations and instructions.
2. Not all ADAS sensors are even meant to be calibrated. Sonar/ultrasonic parking sensors, for example, don’t always require calibration. However, because they are embedded in the bumper, you may be required to replace a damaged bumper with OEM parts. This can mean pricier repairs for consumers.
3. ADAS calibration takes time. The average calibration time is 1.7 hours, with 6 hours max and 1 hour minimum, according to a 2018 IIHS investigation.
4. Many vehicles require both a pre-scan prior to repairs and a post-repair diagnostic scan.
5. Some OEMs, like Nissan, require an alignment rack for their ADAS calibration procedures. This means that mobile ADAS calibration services won’t work for Nissan vehicles.
ADAS calibration is a complex, time-consuming process. But, it’s necessary to keep a vehicle’s advanced safety systems protecting lives, as engineered. Car ADAS Solutions is at the forefront of the ADAS calibration industry. We are a training and consulting firm, specialized in the certification, implementation, and support of start-up ADAS Calibration Centers.
We provide a turn-key solution to opening your own ADAS Calibration Center.
We provide site design, technician certification, equipment, proprietary management system, quality control, and ongoing technical support. Are you interested in owning your own calibration center? Learn More.