There is currently a lot of talk around Advance Driver Assistance Systems (ADAS) in the car market. Car makers are trying to differentiate their vehicles to end customers by implementing more and more so called driving assistant features in the name of increased road safety – but, what are those car electronics assistants doing in detail? Where are they located? What is to be assisted? Where does ARM® come into play? What is the future of Autonomous driving?

The “Eyes” of a Car – Sensors …

Modern cars contain a lot of sensors, which are located on many positions on the outside surface of the car. These sensors can be thought of as the eyes of the car to get a continuous picture of the outer world. The graphic below illustrates where these sensors are, and which areas they are supervising.

Typically those sensors work in different physical dimensions like ultrasonic sound for the near field used for parking aid beepers, infrared light and cameras for the mid range to control wipers during rain or detect pedestrians. Radar is used for long distance control to stop the car for obstacles, such as a pedestrian jumps in your way or for keeping a safe distance with respect to the car in front. Sensors have some local intelligence to pre-process their detection tasks as long wiring cables limit a full bandwidth transport for information to a centralized processing unit in many cases. ARM Cortex®-M cores address areas like ultrasonic parking detection, whereas ARM Cortex-A cores are used for high performance requirements in Field Programmable Gate Arrays (FPGA) for camera systems.

Finally all information delivered by the sensors is processed in a centralized high performance computing cluster ECU (data fusion). ARM addresses this performance requirement levels with its 64-bit ARM Cortex-A50 processor family cores.

The Fundamentals of ADAS …

ADAS systems which will help drivers on various driving conditions, are currently assistance and helping functions only – leaving final decision making to the car driver. The driver is still the topmost ranking decision maker. The driver must have ability to override the electronic assistance in all conditions to prevent failures. The driver is legally responsible for his driving (e.g. you still can use the breaks to get to a full stop even if cruise-control wants to accelerate). You might want to still be able to accelerate if the on-board radar confuses a traffic sign with a pedestrian.

This leads us to the most important thing – don’t smile, it’s vital – there has to be an active driving person in the car while moving. Sorry, no sending the car to a drive-in baker shop in the morning, no nap while driving to the mother-in-law yet, no Knight Rider & K.I.T.T. today …

Mainly this is required by the “Convention on Road Traffic Agreement” signed by many international states at an UN-conference in Vienna/Austria on the 8th of November1968 and currently being deposited at United Nations General Secretary archive. Therefore, almost every autonomous prototype car driving on public roads is granted an exceptional permission from local authorities today.

The fundamental of ADAS is that, in some emergency conditions car electronics aids already can do better than the average commuter – but, are electronics and related software reliable and safe enough to be trusted? Currently this is not the case for all driving conditions. ARM addresses this shortcoming  with  the ARM Cortex-R cores which are designed to address safety related applications for ADAS systems. Current ARM developments even go beyond that level by introducing ARMv8-R architecture features like virtualization to support different operating system flavors on one core. ARM Cortex-R already provides a reliable and centralized brain-of-hardware for silicon inside an ECU-box in the car today.

The Route …

Car makers have decided to go towards a route-of-building-trust to ADAS functionality by introducing car ADAS in a step-by-step approach. They are increasing their own experience levels for a while now and are currently focused on intermediate assistant functions like highway-driving assistance or traffic-jam guidance to get to full autonomous driving as the overall final goal.

Premium cars will be the first to enjoy such technology, with limited autonomous driving in production by ~2020.

Leave a comment