Automotive: Onboard electronics put to the test with ISO 26262

Today, equipped with a host of electronic and computer systems—particularly those designed to assist drivers—cars offer a greater sense of safety. Tomorrow, autonomous vehicles will open up new possibilities for mobility. Voluntary standards, developed by industry professionals themselves, are keeping pace with this evolution.

The widespread adoption of electronics in the automotive industry has necessitated standardized operating procedures. In particular, to ensure functional safety embedded systems. It would have been unrealistic to expect this revolution to succeed without a common language shared among all stakeholders, across industries, and from one country to another! It was with this in mind that the ISO 26262 standard was created in 2011. It adapts the cross-sector IEC 61508 standard for the automotive industry, and today it is available in a brand-new version, dated December 2018.

ISO 26262: A Standard for Road Safety

Comprising twelve parts, ISO 26262 has transformed the landscape of E/E (electrical/electronic) function design in the automotive sector, as well as for motorcycles and trucks, which have been included in the standard’s scope since its revision in 2018. It provides a set of common methods for assessing the safety level of embedded hardware or software. Safety, as defined in the standard, is characterized by the absence of unacceptable risk resulting from system malfunction.

It is calculated based on four safety integrity levels (Automotive Safety Integrity Level), ranging from the least stringent (A) to the most stringent (D), and applies to the system, hardware, and software levels. The standard recommends conducting a safety assessment, carried out by experts who provide their opinion on the safety level achieved by the vehicle. This process must review all issues encountered and serve as a “arbitrator” of safety best practices among automakers.

ISO 26262: Common Protocols

The standard also introduces the concept of a "safety concept." This involves analyzing failures that could compromise safety and specifies measures to prevent them through a set of diagnostics and appropriate degraded modes. For example, in the event of a steering system failure that could lead to a run-off-road situation if left unaddressed, the system will be able to diagnose itself and decide to cut off power assistance. The driver then retains a mechanical connection between the steering wheel and the wheels. However, this requires the definition of standardized protocols.

It’s clear: without a common methodology, there’s no point in relying solely on technology to win users’ trust. Whether you’re Peugeot or Renault, “ensuring a vehicle’s safety requires defining a universal vocabulary and agreeing on a common methodological approach to assess risks, which can vary from one country to another depending on local conditions (infrastructure, weather, etc.),” explains Nicolas Becker, a safety expert for the PSA Group who helped draft the standard.

Toward a Viable Form of Artificial Intelligence

The voluntary ISO 26262 standard addresses failures and the transition to a safe mode. But what happens in the case of autonomous vehicles? Even in the absence of a failure, how can we ensure that artificial intelligence will make the right decision? Upon seeing a trompe-l’œil pedestrian painted on the road, should the system be programmed to trigger emergency braking? To establish these safety protocols, a complementary standard is currently being developed: ISO 21448. Scheduled for release in 2022, it focuses on the safety of driving scenarios, taking into account the vehicle’s environment and potential imperfections in sensors and algorithms.