Testing Can Help to Ensure Effectiveness and Safety
The National Highway Traffic Safety Administration (NHTSA) estimates that 94% of traffic accidents are caused by driver error and the leading cause of these is recognition mistakes.1 Advanced driver-assistance systems (ADAS) can help decrease accidents, injuries, and fatalities by reducing these errors using electronic technologies. In fact, ADAS is one of the fastest-growing sectors in the automotive industry, with expectations that the ADAS market will see a compound annual growth rate (CAGR) of 11.6% by 2027.2
ADAS are designed to increase the safety of vehicles by assisting motorists with driving and parking functions. They use automated technology, such as sensors, cameras, software, lighting, and audio components to detect obstacles and errors, then respond accordingly. ADAS technologies can range from passive to active, alerting drivers to problems, implementing safeguards, and/or taking control of the vehicle.
Passive systems simply give an alert but require the driver to act. Examples might be systems that make noises or vibrate when an object, such as another vehicle or pedestrian, is sensed in a blind spot or as the car drifts into another lane without a turn signal activated. With the warning, the driver needs to take corrective action. On the other hand, active ADAS not only sense the danger, but also automatically activate the required corrective action, such as emergency braking when an obstruction is sensed.
While the systems today are becoming more sophisticated and widely adopted, the general concept of ADAS is not new. The roots of ADAS go back nearly 70 years to anti-lock braking systems (ABS), and today include blind spot information systems, 360-degree cameras, adaptive cruise control, lane departure warnings, traction control, night vision, adaptive lights, collision warning, parking assistance and more. As technology quickly evolves and the industry increasingly moves toward autonomous vehicles, the possibilities for ADAS seem limitless.
ADAS Testing is Essential to Overall Safety
Yet, as ADAS technology is incorporated into vehicles at such an astonishing pace, it is essential to properly evaluate the systems through testing programs that can provide valuable information in developing the advanced technology.
Testing ADAS systems involves exposing a vehicle to situations that trigger the system to intervene, then measuring the outcome to assess system performance. An example of this might be using a mannequin to simulate a pedestrian to test whether the ADAS triggers emergency braking or using simulated cars to determine if collision warning or parking assistance systems are functioning as intended. The testing is monitored, and variables are controlled to ensure the consistent, repeatable application of each test method. Additionally, factors such as weather, dirt, or less optimal road conditions (i.e., lane line deterioration or potholes) can be added to the testing to ensure that the ADAS system goes beyond requirements and provides more robust, usable results.
The methods used to assess and evaluate ADAS come from a variety of sources. For example, the Insurance Institute for Highway Safety (IIHS) includes guidance for automatic emergency braking (AEB) and for AEBs and pedestrians. The European New Car Assessment Programme (NCAP) offers guidance on car-to-car AEB, vulnerable road user AEB, lane support systems, and speed assistance systems. In the U.S., the NHTSA has several guidelines in development covering active parking assistance, blind-spot detection and intervention, intersection and opposing traffic safety assistance, pedestrian AEB, rear automatic braking, traffic jam assists, and heavy vehicle forward collisions warning (FCW). While the NHTSA guidelines have not been finalized, manufacturers and their testing partners can use the draft guidance for product development and assessment.
ADAS system testing provides valuable data that can be used for a variety of needs: validation to OEM standards and requirements, benchmarking to establish design baselines, R&D information, and data for ratings from organizations or programs like IIHS or NCAP. These insights can be quite significant for this increasingly used technology. For example, testing during the R&D and validation phase can help to reduce system redesigns and even the number of formal qualification tests required. Benchmark testing can assess the performance of systems being offered by many manufacturers to set performance requirements and goals. And for programs like NCAP or IIHS, preliminary testing can reduce formal testing and speed up compliance and time to market. The testing can vary from basic (monitoring velocity, direction, location, and response) to intermediate (basic with the addition of audio/video recording) to advanced (adds the capture of the vehicle bus messages for a complete understanding of vehicle behavior and intended response).
The Benefits of Multiple Test Settings
ADAS testing requires facilities and equipment capable of exposing the vehicle to the scenarios that trigger the engagement of those systems. Assessments can be done in the lab, on the road, and/or on proving grounds. Each setting offers its own benefits and drawbacks, and often a combination of these test locations provides the best results.
Here are some of the benefits of each assessment approach:
- Laboratory testing allows for rigorous testing in a highly controlled environment. Engineers can evaluate products for safety, interoperability, functionality, connectivity, overall performance, and controlled environmental exposure to elements such as ultraviolet (UV) light, dust, water intrusion, and more.
- On-road testing uses real-world conditions (including unexpected and random situations) to subject systems to elements like weather, geography, light, infrastructure, obstacles, human activity, and more. Road tests can assess ADAS over an extended period, providing a realistic view of lifespan and functionality.
- Proving ground analysis evaluates products on the road, in a predictable, safe, controlled, and repeatable setting. This method ensures specific elements are included in the evaluation, such as direct sunlight, weather conditions, tunnels, on-ramps, and other potential obstacles. Testing can be configured to duplicate real-world environments and applications, depending on the design and capability of the proving ground.
A thorough test plan will integrate testing in multiple environments to provide robust, comprehensive data and actionable results. Some equipment and components will require lab assessments for items such as electrical safety, electromagnetic compatibility (EMC), performance, and other considerations. These same pieces of equipment and the overall system can then be sent to the proving ground for realistic, on-road assessments to see how they perform in action. Additional lab testing may then be required to help assess how the equipment has responded to those scenarios. For example, it may illustrate whether on-road usage impacts electrical safety or overall system functionality.
ADAS Testing Equipment Requirements
The equipment used to evaluate ADAS can vary both in type and number of testing systems and devices needed. For example, assessing how ADAS functions in a traffic jam will be more complex than assessing how it interacts with a pedestrian. More components will be needed to simulate the traffic jam, thus more equipment is used and more data collected. ADAS assessments will commonly include the use of several types of equipment, as follows:
- Inertial measurement systems capable of real-time kinematics, or RTK: These are used to assess things like speed, position, force, angular rate, and orientation. Because data needs to be pulled as the car is in motion and as systems are reacting, real-time kinematics are important for accuracy.
- Guided soft targets: Used to simulate other cars, guided soft targets are self-propelled platforms and aerodynamically stable. However, because they are soft targets, when they come into contact with a vehicle, they will break apart and not cause damage to the test car and on-board systems.
- Other soft targets: Used to simulate people (both adults and children) who are moving or static, as well as bicycles and other obstacles. They replicate the size, shape, and, when needed, the motion of the object to assist in evaluating the response to encountering these objects.
- Driving robots: Driving robots, such as steering robots, pedal robots, provide repeatable, accurate control of the vehicle and use RTK for speed and position corrections for accurate path following. The use of robots versus humans allows for multiple evaluations with less variability to factors like speed, control, path, angles, and impact.
- Controller Area Network (CAN) decoding/recording equipment: CAN equipment allows for communication, data gathering, and recording without a host computer. Commonly used for in-vehicle communications since the 1980s, it provides low-cost, lightweight networks for the communication of data and information.
- Additional rear-vehicle targets: Simulates items such as buildings, lighting, signs, and other obstacles a car may encounter in reverse.
- Various road and intersection types: Used to assess systems such as AEB, blind-spot detection, and testing for intersections and traffic jams. These include different surfaces and speeds to ensure more comprehensive data.
- Different test environments: Varying environments, such as parking lots, highways, traffic jams, cities, rural roads, and more, are important to assess various systems such as AEB, parking assistance, lane keep/centering, customized tests, and more.
A Comprehensive Test Plan is Essential
Given the variety of test settings and equipment that can be used, it is important to establish a comprehensive test plan before evaluations begin. Start the process with the end goal in mind: Why are you testing? What information do you need? Then proceed to identify the best way to get the information needed. This will determine where the testing needs to be done, when, what equipment and environmental conditions are required, what data is needed, and how the data will be collected and, ultimately, analyzed. Once a test plan is in place, the ADAS evaluation can begin.
ADAS testing begins with preliminary set up and practice days, which can be beneficial for reducing downtime and completing the tests in a time-efficient manner. At this stage, engineers can map test surfaces and create different routes to ensure that the necessary test environments, lane configurations, and test targets are accounted for.
This preliminary phase can also include other recommendations to ensure time-effective testing. This might include planning and scheduling remote software resources for immediate updates, pre-testing software subroutines, and ensuring maintenance tools and lifts are available to fix any mechanical issues. Validating test system set up, confirming test equipment like RTK systems function properly, and making sure proper technical support is on hand to troubleshoot any challenges is always a high priority to limit downtime once testing begins.
After this preliminary stage, testing can be completed. It may take a few days to gather all the necessary data, especially if the test plan includes a combination of lab evaluations and on-road/proving ground analysis. Test set up and completion could also take time, especially as simulations are conducted. As with any testing, it is important to be prepared for the reality that test runs, data collection, compilation, and analysis can be a lengthy process. In the end, though, the information provided is invaluable in ensuring the quality, performance, and safety of ADAS and the vehicles where they are present.
Conclusion
As the automotive industry seeks to find better ways to help ensure the safety of drivers, pedestrians, property, and vehicles, ADAS offers the technology and ability to reduce driver error and, as such, accidents. They also provide consumers with the benefits of convenience and safety. As the technology and use of these systems continue to advance at a high rate, ensuring their functionality and safety is critical. It is important to know the requirements in place for these systems, as well as the supplemental assessments that apply to ADAS.
Knowing what information is needed and how to find it, then partnering with experienced, knowledgeable engineers to prepare and execute a test plan, can help provide valuable information for R&D, benchmarking, marketing, regulatory purposes, and more. Safer ADAS can mean safer vehicles and safer transportation for everyone.
