Advancements in the auto industry are always a popular topic of conversation. From fuel efficiency to infotainment, cars are seen as transportation, entertainment, and status symbols all over the world. Embedded technologies are driving key initiatives in the industry:

• Green – Environmentally friendly and fuel efficient.
• Smart – Greater visibility, alters using sensor, actuator, and camera technologies
• Safe – Collision safety features to reduce injury and road fatalities.

Focusing on the “smart” initiative, advanced driver assistance systems (ADAS) are expected to advance from assisted driving today to highly automated driving in 2020 to autonomous driving by the year 2025 (Figure 1). If this vision is realized, in ten short years, autonomous driving will be a reality – though Tesla claims it’ll have autonomous driving in its cars by summer 2015!

ADAS are the stepping stones toward autonomous driving. An interconnected network of cameras, video analysis, sensors, and global positioning systems provide the building blocks upon which the auto of the future will be built.

Automotive standards

The European New Car Assessment Programme (Euro NCAP) is a driving force in the assessment and advancement of these key initiatives in the auto industry. Euro NCAP performs crash tests as well as test protocols for validating active safety systems through simulation. These test simulations are used to assess the five-star rating system assigned to various makes and models.

Environmental regulations are becoming tougher and higher safety standards are being applied. In order to address these challenges, auto developers and their suppliers need access to the right embedded tools and simulation environments in order to achieve the desired ratings.

Simulation to real-world test

I got the opportunity to talk with Mahendra Muli, Director of Marketing and New Business Development at dSPACE, about Euro NCAP and the challenges involved with the testing required to ensure functional safety.

Mahendra describes ADAS and active safety systems development as a pipelined process shown in Figure 2.

Open-loop testing provides an environment where engine controller unit (ECU) algorithms can be developed and validated within a realistic context. Closed loop simulation is used in the early development stages to provide a higher quality production candidate. Simulation should also be able to occur in real-time or faster than real-time.

These models can then be used to perform early integration testing. Integration tests can be run with virtual ECUs at this point and the tests can be prepared and validated for use within the hardware-in-the-loop (HIL) testing.

Once the software-in-the-loop (SIL) testing is complete, the same tools, models, layouts, and tests can be utilized within the HIL testing. At this point the ECU tests can also be automated.

The process and simulation environment provides for testing of actuators, radar sensors, and camera sensors involved in things like lane departure warning, emergency braking, and pedestrian detection. Mahenda cited test cases dSPACE has been involved in using their ControlDesk, MotionDesk, and AutomationDesk simulation environment suite for testing lane departure warning (LDW) systems and autonomous emergency braking (AEB).

Euro NCAP test scenarios

The Euro NCAP test scenarios for autonomous emergency braking involve approaching a stationary target in city and urban environments, approaching a slower target, and approaching a braking target. Each scenario involves a vehicle speed between 50-80 km/h with distance to target calculations and operation that provides controlled braking to eliminate or minimize impact.

There are also similar test scenarios for AEB involving pedestrian or vulnerable road users (VRU) like bicycles or motorcycles. Mahendra mentioned that these test scenarios are not finalized and may be subject to change by Euro NCAP. Mahendra mentioned that the dSPACE simulation environment provides a library with Euro NCAP test scenarios that allow the user to execute the tests and generate score results. The same test framework can be used for model, software, and hardware testing.

Improving vehicle safety and functionality

ADAS and active safety systems are gaining importance and new challenges are emerging to ensure functional safety of these systems. Virtual test drives and early simulation and testing are becoming a critical factor in providing better modeling, higher quality algorithms, and faster development of advanced driver assistance systems for the automobile.

Reference

Mahendra Muli, Active Safety Symposium 2014, Automated Testing of Active Safety Systems According to Euro NCAP Test Methods.