Visible to the public File preview

Automotive System Safety Engineering Practitioner Knowledge
Joseph D’Ambrosio
ISO 26262 Automotive Functional Safety Technical Expert (ISO/TC22/SC3/WG16 Member) Lab Group Manager GM Research Laboratories

Outline
 ISO 26262 Overview  ISO 26262 Competence Management  ISO 26262 Safe SW Development

What is ISO 26262?
 Adaptation of IEC 61508 to comply with the specific needs of E/E systems within road vehicles
 Specifies a functional safety life-cycle for automotive products

 

Applies to all activities during the safety lifecycle of safety-related systems comprised of electrical, electronic, and software components Is a standard, not a regulation
 Broad industry participation in its development  Indication of broad industry adoption  Expected Publication Date: Nov. 15

 Key concept: Automotive Safety Integrity Level (ASIL)
 Specify risk associated with a potential hazard  Specifies development requirements to achieve targeted integrity levels with respect to systematic and random hardware failures

Overview of ISO/DIS 26262

Source ISO/FDIS 26262

Outline
 ISO 26262 Overview  ISO 26262 Competence Management  ISO 26262 Safe SW Development

ISO 26262 Competence Management
 Part 2, 5.4.3.1 “The organization shall ensure that the persons involved in the execution of the safety lifecycle have a sufficient level of skills, competences and qualifications corresponding to their responsibilities.”

Source ISO/FDIS 26262

ISO 26262 Competence Management
 Part 2, 5.4.3.1 Note 1 – “One of the possible means to achieve a sufficient level of skills and competences in development is a training and qualification programme that considers the following knowledge areas:
● ● ● ● usual safety practices, concepts and designs; ISO 26262 and, if applicable, further safety standards; organization-specific rules for functional safety; functional safety processes instituted in the organization.”

Source ISO/FDIS 26262

ISO 26262 Competence Management
 Part 2, 5.4.3.1 Note 2 – “To evaluate the skills, competences and qualifications to carry out activities to comply with ISO 26262, the experience from previous professional activities can be considered, e.g.
● domain knowledge of the item; ● expertise on the environment of the item; ● management experience.”

Source ISO/FDIS 26262

ISO 26262 Lifecycle Steps
 Safety Management
● Process Management ● Design Confirmation Including Reviewers

 Safety-Critical Systems Development
● Systems Development & Testing ● SW Development & Testing ● HW Development & Testing

 Distributed Development Management …

“Usual System Safety Concept” from ISO 26262
 Hazard Analysis and Risk Assessment  Safety Concept Development
● Functional safety requirements ● Technical safety requirements

 Safety Analysis
● HW & SW FMEA, FTA, Modeling & Simulation Tools

 Diagnostic & Remediation Strategies
● Diagnostic Methods ● Microcontroller and circuit board concepts

 Verification & Validation
● HW / SW testing methods, including unit, integration, bench, vehicle

 Functional Safety Assessment / Safety Case

Outline
 ISO 26262 Overview  ISO 26262 Competence Management  ISO 26262 Safe SW Development

Software Development

Reference Phase Model for the Software Development

Source ISO/FDIS 26262

SW Development Work Products
 Safety plan (refined)  Software verification plan  Design and coding guidelines for modelling and programming languages  Software tool application guidelines  Software safety requirements specification  Hardware-software interface specification (refined)  Software verification plan (refined)  Software verification report  Software architectural design specification  Safety analysis report  Dependent failures analysis report  Software unit design specification  Software unit implementation  Software verification specification (refined)  Embedded software

Source ISO/FDIS 26262

SW Architecture Design Reorientation

Source ISO/FDIS 26262

SW Architecture Design

Source ISO/FDIS 26262

SW Architecture Design

Source ISO/FDIS 26262

Software Unit Design Representation

Source ISO/FDIS 26262

SW Unit Design Methods

Source ISO/FDIS 26262

Coding Guidelines

Source ISO/FDIS 26262

Example Software Unit Design Table

Source ISO/FDIS 26262