Parasoft Logo

ISO 26262 Software Compliance: Achieving Functional Safety in the Automotive Industry

Introduction: Functional Safety In The Automotive Industry

Safety functions are increasingly being carried out by electrical, electronic, or programmable electronic systems. These systems are usually complex, making it impossible in practice to fully determine every failure mode or to test all possible behavior. Although it is difficult to predict the safety performance, testing is still essential. The challenge is to design the system in such a way as to prevent dangerous failures or to control them when they arise.

Safety is one of the key issues of today’s and tomorrow’s automobile development. New functionality—not only in the area of driver assistance, but also in vehicle dynamics control and active and passive safety systems—increasingly touches the domain of safety engineering. Future development and integration of these functionalities will further strengthen the need to have safe system development processes and to provide evidence that all reasonable safety objectives are satisfied.

With the trend of increasing complexity, software content, and mechatronic implementation, there are rising risks of systematic failures and random hardware failures. ISO/DIS 26262 includes guidance to reduce these risks to a tolerable level by providing feasible requirements and processes.

The purpose of this document is to detail how the use of Parasoft C/C++test can help automotive software development organizations achieve compliance with ISO/DIS 26262. It first introduces the ISO/DIS 26262 standard and its goals. Next, it describes Parasoft C/C++test: an integrated solution for automating best practices in software development and testing. Finally, it presents the areas of the ISO/DIS 26262 standard that can be fully or partially satisfied using Parasoft C/C++test.

About ISO/DIS 26262

ISO/DIS 26262 is the adaptation of IEC 61508 to comply with needs specific to the application sector of E/E systems within road vehicles. The Draft International Standard (DIS) is the latest version that is publicly available since June 2009. The International Standard (IS) is planned for June 2011.

ISO/DIS 26262:

  • Provides an automotive safety lifecycle (management, development, production, operation, service, decommissioning) and supports tailoring the necessary activities during these lifecycle phases.
  • Provides an automotive-specific risk-based approach for determining risk classes (Automotive Safety Integrity Levels, ASILs).
  • Uses ASILs for specifying the item’s necessary safety requirements for achieving an acceptable residual risk.
  • Provides requirements for validation and confirmation measures to ensure a sufficient and acceptable level of safety is being achieved.

ISO/DIS 26262 covers functional safety aspects of the entire development process (including such activities as requirements specification, design, implementation, integration, verification, validation, and configuration).

Part 6 of the standard document specifically addresses the product development at the software level. This involves requirements for the initiation of product development at the software level, specification of software safety requirements, software architectural design, software unit design and implementation, software unit testing, software integration and testing, and verification of software safety requirements.

Methods defined by the ISO/DIS 26262 standard should be selected depending on the ASIL, i.e. the higher the ASIL, the more demanding the methods that need to be applied.

The use of software tools simplifies or automates activities and tasks required for the development of a safety-related item or element by ISO/DIS 26262. Part 8, section 11 of the standard document describes the process of qualification of the software tools. The qualification of software tools is to provide evidence of software tool suitability for use when developing a safety-related item or element, such that confidence can be achieved in the correct execution of activities and tasks required by ISO/DIS 26262…