Introduction to ISO 26262

ISO 26262 is an international standard for functional safety in the automotive industry. It provides guidelines and requirements for developing safety-critical automotive systems to ensure safe operation throughout lifecycle. The standard focuses on the development of electrical and electronic systems in road vehicles, aiming to minimize the risks associated with potential hazards caused by malfunctioning electronics.

As one can see from the chart below, there are 11 sections in ISO 26262 standard; each one will be explained in detail, and I will provide examples.

ISO 26262 defines a framework for various aspects of functional safety, and those include:?

1. Vocabulary: Set of terms and definitions to remove ambiguity in the management of functional safety
2. Management of Functional Safety: This involves processes and activities for managing safety requirements, risk assessment, and safety verification and validation.
3. Concept Phase: In this phase, system requirements are defined, and potential hazards are identified. The safety goals and integrity levels are established.
4. Product Development at the System Level: This phase includes the design and implementation of the system architecture to achieve the defined safety goals.
5. Product Development at the Hardware Level: Safety-related hardware components are designed, including sensors, processors, and other electronic components.
6. Product Development at the Software Level: Safety-related software components are developed, including software architecture, coding, and testing.
7. Production and Operation: Safety measures during production, operation, and maintenance of the vehicle are addressed to ensure that the safety goals are maintained.
8. Supporting Processes: Various supporting processes, such as configuration management, change management, and documentation, are outlined to ensure safety is maintained throughout the system's lifecycle.
9. ASIL (Automotive Safety Integrity Level): ISO 26262 introduces a classification system for the assessment of the inherent safety risk associated with a hazard. This classification system ranges from ASIL A (lowest risk) to ASIL D (highest risk).
10. Guidelines on ISO 26262
11. Guidelines on Application of ISO 26262 to Semiconductors

ISO 26262 is widely adopted in the automotive industry to ensure that electronic systems in vehicles are designed, developed, and maintained with a focus on safety. It aims to reduce the risk of accidents caused by electronic malfunctions and failures in modern vehicles.

?

1. Vocabulary

The Vocabulary section in ISO 26262 is a foundational part of the standard that defines key terms and concepts used throughout the document. It aims to establish a common understanding of terminology within the context of functional safety for road vehicles. By providing precise definitions, the Vocabulary section helps ensure clarity and consistency in the interpretation of the standard.

Examples of some of the key items of terminology as provided in the standard are the following:

2. Management of Functional Safety

The Management of Functional Safety is a critical aspect of the ISO 26262 standard. It involves the processes and activities that an organization needs to establish and maintain to ensure the development of safe and reliable automotive systems.?

Here's a more detailed breakdown of the Management of Functional Safety:

2.1 Overall Safety Management

Overall Safety Management is a concept that focuses on establishing and maintaining a systematic approach to managing functional safety throughout the entire lifecycle of a safety-critical automotive system. It encompasses various activities, responsibilities, and processes that organizations must implement to ensure that safety risks associated with the system are properly identified, assessed, and managed.

Here are the key aspects of Overall Safety Management within the ISO 26262 framework, along with examples to illustrate each aspect:

1.?????? Safety Culture and Organizational Structure:

Organizations must establish a safety culture that prioritizes safety as a fundamental value throughout all levels of the organization.

• Example: Regular safety training sessions for employees, where safety principles, best practices, and the importance of safety are emphasized.

2.?????? Safety Goals and Safety Requirements:

Organizations must define safety goals, derive safety requirements that guide the development process, and ensure the system operates safely.

• Example: A safety goal could be "Ensure that the brake system activates within a certain time threshold when a potential collision is detected."

3.?????? Allocation of Safety Integrity Levels (ASIL):

Organizations must assign ASILs to different functions based on the potential severity of their failures.

• Example: A function responsible for airbag deployment might be assigned a higher ASIL (e.g., ASIL D) than a function controlling interior lighting (e.g., ASIL A).

4.?????? Safety Management Plan:

Organizations must develop a safety management plan that outlines the safety processes, activities, and responsibilities to ensure that functional safety is properly managed.

• Example: Documenting the sequence of safety analysis activities to be conducted during different phases of development.

5.?????? Safety Verification and Validation:?

Organizations must implement processes to verify and validate that safety requirements are met and that the system operates safely.

• Example: Performing simulation tests to ensure the vehicle's electronic stability control system can prevent skidding under various road conditions.

6.?????? Safety Case:

Organizations must compile a safety case that provides evidence of the system's safety through the entire lifecycle, including safety analyses, verification results, and validation outcomes.

• Example: Document the hazard analysis results, risk assessment, and safety measures to mitigate identified risks.

7.?????? Change Management:

Organizations must establish processes to manage system changes to ensure safety is not compromised.

• Example: Implementing a Change Review Board that assesses the impact of proposed design changes on safety and decides whether they can be implemented.

8.?????? Safety Audits and Assessments:

Organizations must conduct safety audits and assessments to ensure safety processes are followed and safety requirements are met.

• Example: An independent third party conducting a safety audit to evaluate the organization's compliance with safety standards and best practices.

2.2 Project Dependent Safety Management

Project Dependent Safety Management is a concept that addresses the adaptation of functional safety management processes and activities to individual projects' specific characteristics and requirements. It recognizes that different projects may have varying levels of complexity, safety goals, and challenges, and therefore, the safety management approach needs to be tailored accordingly.

Here are the key aspects of Project Dependent Safety Management within the ISO 26262 framework, along with examples to illustrate each aspect:

1. Adapting Safety Goals and Requirements:

Safety goals and requirements must be tailored to the specific project and the safety-related functions being developed.

• Example: For an autonomous driving project, safety goals include maintaining a safe distance from other vehicles and pedestrians under various traffic conditions.2. Customizing Safety Activities:

The scope and depth of safety activities, such as hazard analysis and risk assessment, can vary based on project complexity and safety implications.

• Example: For a project involving a simple infotainment system, the hazard analysis might focus on software errors affecting user experience rather than critical safety functions.3. ASIL Determination and Allocation:

The assignment of Automotive Safety Integrity Levels (ASILs) to functions should consider the project's specific safety requirements and potential consequences of failures.

• Example: In a project developing a driver assistance system, functions related to collision avoidance might be assigned higher ASILs than functions associated with climate control.4. Project Safety Management Plan:

Develop a safety management plan that outlines how safety activities will be conducted, resources allocated, and responsibilities assigned for the specific project.

• Example: A project safety plan might detail the sequence of safety analyses, verification tests, and safety audits specific to a new electric vehicle model.5. Verification and Validation Strategies:

Customized strategies for verifying and validating safety requirements based on the project's characteristics and the associated safety goals.

• Example: A complex autonomous parking system project might require extensive simulation testing in diverse parking scenarios.6. Change Management:

The change management process should be adapted to the project's needs, ensuring safety is not compromised when modifications are made.

• Example: When updating the software in an electric vehicle's battery management system, thorough testing should be performed to ensure that new algorithms don't cause overcharging.7. Project-specific Safety Assessments:

Conduct assessments to evaluate the project's safety management approach, adherence to safety processes, and compliance with safety requirements.

• Example: An assessment might review the integration of multiple safety-critical systems in a high-performance sports car, focusing on minimizing latencies.8. Communication and Collaboration:

Effective communication and collaboration among cross-functional teams are crucial for project-dependent safety management.

• Example: Engineers working on powertrain development must collaborate closely with those responsible for the vehicle's advanced driver assistance systems to ensure compatibility and safety.

2.3?? Safety Management regarding production, operation, service, and decommissioning

Safety Management regarding production, operation, service, and decommissioning emphasizes the need to ensure the ongoing safety of a vehicle or automotive system during its development phase and throughout its entire lifecycle, including manufacturing, operation, maintenance, and eventual decommissioning. This section focuses on processes and measures that need to be in place to address safety concerns and maintain functional safety in these various lifecycle stages.

Here are the key aspects of Safety Management regarding production, operation, service, and decommissioning within the ISO 26262 framework, along with examples to illustrate each aspect:

1. Production Phase:

During the production phase, safety-critical components and systems must be manufactured and assembled to maintain their integrity and safety.

• Example: Implementing quality control processes to ensure that electronic control units (ECUs) are manufactured without defects that could compromise their safety functions.

1. Operation Phase:

The operational phase ensures that the vehicle or system operates safely and as intended throughout its use.

• Example: Monitoring and diagnosing sensors and actuators in real-time to detect potential faults that could impact the performance of advanced driver assistance systems.3. Service Phase:

During routine maintenance and service, addressing any potential safety concerns and ensuring that the system continues to function safely is essential.

• Example: Updating software in a vehicle's infotainment system to fix vulnerabilities that malicious parties could potentially exploit.4. Decommissioning Phase:

When a vehicle or system reaches the end of its useful life, decommissioning should be carried out in a way that minimizes safety risks and environmental impact.

• Example: Properly disposing of electric vehicle batteries, adhering to environmental regulations, and ensuring they don't pose safety risks during recycling.5. Safety Monitoring and Reporting:

Establish processes to monitor safety performance and report safety-related incidents or concerns continuously.

• Example: Using advanced driver assistance features, setting up a mechanism for users to report any abnormal behavior or safety issues encountered.6. Recall and Maintenance Strategies:

Define strategies for handling recalls, updates, and maintenance actions to address safety-related issues that might arise after the product has been deployed.

• Example: Initiating a recall for vehicles equipped with a faulty airbag sensor that might not deploy the airbag in case of a collision.7. Documentation and Communication:

Maintain documentation that tracks safety-related activities and changes throughout the product's lifecycle. Ensure that safety-related information is communicated to stakeholders.

• Example: Keeping a comprehensive record of software updates and modifications to safety-critical systems for auditing and accountability.8. End-of-Life Considerations:

Address safety aspects when a product reaches the end of its life, ensuring that its disposal or recycling does not pose safety or environmental risks.

• Example: Designing electric vehicle systems to facilitate safe battery removal and recycling when the vehicle reaches the end of its operational life.

?

3. Concept Phase

The Concept Phase is a critical starting point in developing a safety-critical automotive system. It sets the foundation for identifying safety goals, understanding potential hazards, and outlining the high-level functional safety concept.

Let's break down the Concept Phase into its sections and provide examples for each:

3.1. Item Definition:

This section defines the scope and boundaries of the safety-critical item being developed. That involves understanding the item's functions, interfaces, and role within the larger system.

Subsections:

• Item Identification and Description: Identify and describe the safety-critical item, its functions, and its interfaces with other components or systems.

• Example: Identification and description of an adaptive cruise control system, outlining its role in maintaining a safe distance from other vehicles.

1.?????? Description: The adaptive cruise control system is responsible for maintaining a safe following distance from the vehicle ahead by automatically adjusting the vehicle's speed.

2.?????? Interfaces: Interfaces with the vehicle's engine control, brake system, radar sensors, and user input.

3.2. Hazard Analysis and Risk Assessment (HARA):

This section systematically identifies potential hazards, assesses their associated risks, and determines the appropriate safety measures to mitigate them.

Subsections:

• Hazard Identification: Identify potential hazardous events that could lead to harm or damage.

Example: Hazard identification could include scenarios where the adaptive cruise control system fails to detect a slower-moving vehicle in the same lane.

1.?????? Description: The adaptive cruise control system fails to detect a slower-moving vehicle in the same lane.

2.?????? Effects: Risk of rear-end collision due to inadequate deceleration.

3.?????? Exposure: Frequent use of cruise control in moderate to heavy traffic conditions.

4.?????? Controllability: High controllability through redundant sensor inputs and algorithm improvements.

5.?????? ASIL Assignment: ASIL D

6.?????? Rationale: The hazard of not detecting a slower-moving vehicle is of moderate severity and high exposure. However, with the use of redundant sensors and continuous algorithm enhancements, the risk can be significantly reduced.

• Risk Assessment: Evaluate the severity and exposure of each hazard to estimate the associated risk level.

Example: Assessing the risk of a collision due to the failure of the adaptive cruise control system to decelerate the vehicle in response to traffic conditions.

• ASIL Allocation: Allocate an Automotive Safety Integrity Level (ASIL) to each hazard based on risk level.

Example: Assigning an ASIL D to a hazard associated with a collision due to the failure of the adaptive cruise control system in high-speed scenarios.

?

• Risk Mitigation Measures: Determine measures to reduce identified risks to acceptable levels for each hazard.

Example: Implementing redundancy in sensor inputs and adding fail-safe mechanisms to ensure the adaptive cruise control system responds appropriately to different situations.

3.3. Functional Safety Concept:

This section defines the high-level concept for achieving functional safety, including system architecture, redundancy, and safety mechanisms.

Subsections:

• Functional Safety Requirements: Define safety requirements that ensure the safety-critical item operates as intended.

Example: Requiring that the adaptive cruise control system maintains a minimum safe distance from the vehicle in front and can override user input if necessary.

1.?????? Description: The adaptive cruise control system must maintain a minimum safe following distance from the vehicle in front.

2.?????? Requirement: The system shall maintain a minimum following distance equivalent to a time-to-collision (TTC) of at least 2 seconds.

• ?Safety Mechanisms and Architecture: Define the architectural elements that support safety, such as redundant sensors, fail-safe modes, and diagnostic functions.

Example: Implementing redundant radar and camera sensors to ensure reliable detection of surrounding vehicles.

1.?????? Description: The adaptive cruise control system utilizes redundant radar and camera sensors to enhance object detection accuracy.

2.?????? Architecture: The system incorporates two radar sensors and a camera sensor to validate and cross-check detected objects.

• Dependability Metrics: Define metrics for measuring the dependability of the safety-critical item.

Example: Defining metrics for the system's Mean Time Between Failures (MTBF) and Mean Time to Repair (MTTR) for maintenance purposes.

1.?????? MTBF: The adaptive cruise control system shall demonstrate an MTBF of at least 100,000 operating hours.

2.?????? MTTR: The system shall have a mean time to repair of no more than 1 hour for diagnostic and maintenance tasks.

By addressing each section and its subsections in the Concept phase, automotive engineers lay the groundwork for a comprehensive understanding of the safety-critical item's functions, potential hazards, and the overarching functional safety concept. This information guides subsequent phases of development, verification, validation, and more within the ISO 26262 framework.

4. Product Development at the System Level

The Product Development at the System Level phase of ISO 26262 involves the design, integration, and verification of the entire safety-critical automotive system. This phase ensures that the system as a whole meets the functional safety requirements established in earlier phases and is capable of achieving the defined safety goals. The goal is to create a system that operates reliably and safely under various conditions.

Here's a breakdown of the Product Development at the System Level phase, divided into sections along with examples for each subsection:

4.1. General Topics for the Product Development at the System Level:

In this section, general aspects related to the development of the safety-critical system are addressed.

Subsections:

• Development Interface Agreement: Define agreements and interfaces between different development teams and disciplines. Example: Establishing clear communication protocols between the hardware and software development teams for an engine control system.
• Responsibility and Authority: Assign responsibilities and authorities for different aspects of system development. Example: Designating a chief safety officer responsible for overseeing and ensuring the implementation of safety measures across the entire system.

4.2. Technical Safety Concept:

This section focuses on creating a detailed technical plan for implementing safety mechanisms and ensuring functional safety.

Subsections:

• Functional Safety Requirements Allocation: Allocate safety requirements to system components based on their functions. Example: Allocating the requirement of maintaining a safe distance to the adaptive cruise control algorithm and brake system.
• Safety Architecture and Concept: Define the architecture that incorporates redundancy, fail-safe mechanisms, and diagnostic functions. Example: Implementing safety architecture for an autonomous emergency braking system that includes redundant braking actuators and sensors.

4.3. System and Item Integration and Testing:

This section deals with integrating system components and testing them for safety and functionality.

Subsections:

• Integration of Safety Requirements: Integrate safety requirements into the overall system design. Example: Integrating safety requirements related to communication between the airbag system and impact sensors.
• System Integration Testing: Perform integration tests to ensure that system components work together as intended. Example: Testing the interaction between the adaptive cruise control system and the lane departure warning system under different scenarios.

4.4. Safety Validation:

This section involves validating the safety mechanisms and functional safety of the system.

Subsections:

• Validation Plan and Specification: Develop a plan and specifications for validating the safety measures and functional safety. Example: Defining a validation plan that outlines tests to demonstrate the effectiveness of fault detection mechanisms in an electric power steering system.
• Validation of Safety Mechanisms: Conduct tests to validate the safety mechanisms implemented in the system. Example: Testing the response time of a fail-safe mechanism that activates when a fault is detected in the brake-by-wire system.

The Product Development at the System Level phase results in a well-integrated and validated safety-critical automotive system. This phase ensures that the system's design, architecture, and mechanisms align with safety goals and functional safety requirements. The phase sets the stage for further activities such as hardware and software development, as well as safety validation and certification processes.

?

It's important to note that the specific implementation and practices within this phase can vary based on the complexity of the system, the manufacturer's approach, and the specific safety goals of the system being developed. ISO 26262 provides a structured framework, called V-Model, to guide these activities and ensure that safety considerations are at the forefront of system development.

4.5 V-Model

The V-Model, also known as the Verification and Validation Model, is a widely used development approach in the context of safety-critical systems, including those governed by ISO 26262.

The picture below shows that the V-Model is used throughout the System, Hardware, and Software development phases:

The V-Model is used to illustrate the relationship between development phases and corresponding testing phases, emphasizing the importance of verification and validation activities throughout the product development lifecycle. It serves as a framework to ensure that each development phase is paired with a corresponding testing phase, helping to mitigate risks and ensure that safety requirements are met.

In the Product Development at the System Level phase, the V-Model can be applied as follows:

Requirements Phase:

• Development Activities: In this phase, the technical safety concept and system architecture are defined. Safety goals, requirements, and specifications are established.
• Testing Activities: Corresponding verification activities include reviewing safety requirements, architecture, and technical safety concept. This ensures that the requirements are accurately captured and well-defined.

Architectural Design Phase:

• Development Activities: In this phase, the high-level architecture of the system is designed, considering safety mechanisms, redundancy, and fail-safe features.
• Testing Activities: Verification activities involve reviewing the architectural design to ensure it aligns with safety goals and requirements. The emphasis is on confirming that the design supports the safety concept.

Integration and Testing Phase:

• Development Activities: Components are integrated to form the complete system. Safety mechanisms are implemented, and the overall functionality is tested.
• Testing Activities: Integration testing takes place, validating the interactions between different components and ensuring they function as intended to achieve the defined safety goals.

Validation Phase:

• Development Activities: Safety validation is performed, which involves comprehensive testing to demonstrate that the system meets the established safety goals and requirements.
• Testing Activities: Validation testing is conducted to verify that the system operates as expected under various real-world scenarios, providing evidence that the safety goals are achieved.

The V-Model's "V" shape signifies the parallelism between development and testing phases. The left side of the "V" represents the development phases, while the right side represents corresponding testing phases. The point of the "V" represents the point of system integration and verification, where the system's components are integrated and then validated to ensure that they meet safety requirements.

Applying the V-Model in the Product Development at the System Level phase ensures that safety considerations are systematically integrated into the development process, helping to identify issues early, reduce risks, and ultimately deliver a safety-critical system that meets the required functional safety standards.

?

5. Development at the Hardware Level

The Product Development at the Hardware Level phase involves the creation of the hardware components that make up the safety-critical automotive system. This phase ensures that these hardware components are designed and verified to meet the functional safety requirements established in earlier phases. The goal is to build reliable and fail-safe hardware that contributes to the overall safety of the system.

Here's a breakdown of the Product Development at the Hardware Level phase divided into sections along with examples for each subsection:

5.1. General Topics for the Product Development at the Hardware Level:

In this section, general aspects related to hardware development for the safety-critical system are addressed.

Subsections:

• Development Interface Agreement: Define agreements and interfaces between different hardware development teams and other disciplines. Example: Ensuring proper communication between hardware designers, software developers, and functional safety engineers for an engine control module.
• Responsibility and Authority: Assign responsibilities and authorities for different aspects of hardware development and safety. Example: Designating a chief hardware engineer responsible for overseeing hardware design activities and ensuring safety requirements are met.

5.2. Specifications of Hardware Safety Requirements:

This section involves specifying safety requirements for the hardware components of the system.

Subsections:

• Hardware Safety Requirements Allocation: Allocate hardware safety requirements to specific hardware components and functions. Example: Allocating the requirement for fault tolerance to redundant braking sensors in an anti-lock brake system.
• Hardware Safety Requirements Derivation: Derive specific hardware safety requirements from higher-level functional safety requirements. Example: Deriving a requirement for single-point fault tolerance in the microcontroller responsible for engine control.

5.3. Hardware Design:

This section focuses on designing hardware components that meet safety requirements.

Subsections:

• Hardware Architecture and Design: Develop the architecture and design of hardware components to ensure safety and reliability. Example: Designing a redundant power supply system for an electronic stability control module to prevent power loss.
• Design for Hardware Systematic Failures: Implement design practices to mitigate systematic hardware failures. Example: Using error correction codes (ECC) in memory components to detect and correct data corruption.

5.4. Evaluation of the Hardware Architectural Metrics:

This section involves evaluating hardware architectural metrics for safety.

Subsections:

• Hardware Metrics Evaluation Plan: Develop a plan for evaluating hardware architectural metrics. Example: Creating a plan to assess hardware metrics such as diagnostic coverage and fault latency in an airbag deployment system.
• Evaluation of Diagnostic Coverage: Evaluate the diagnostic coverage of hardware components to ensure fault detection. Example: Assessing the diagnostic coverage of sensors and actuators in an adaptive cruise control system.

5.5. Evaluation of Safety Goal Violations Due to Random Hardware Failures:

This section addresses the evaluation of safety goals in case of random hardware failures.

Subsections:

• Hardware Metrics Evaluation for Random Hardware Failures: Evaluate hardware metrics to determine safety goal violations caused by random hardware failures. Example: Analyzing the impact of a random hardware failure in a braking system on the system's ability to maintain a safe distance from the preceding vehicle.

5.6. Hardware Integration and Verification:

This section involves integrating hardware components and verifying their safety.

Subsections:

• Hardware Integration: Integrate hardware components into the overall system architecture. Example: Integrating hardware components like sensors, microcontrollers, and power supplies into an advanced driver assistance system.
• Hardware Verification: Verify the functionality and safety of hardware components through testing and analysis. Example: Testing the response time of redundant sensors in a lane departure warning system to ensure accurate and timely warnings.

The Product Development at the Hardware Level phase results in the creation of hardware components that are not only functional but also compliant with safety requirements. These hardware components contribute to the overall reliability and safety of the automotive system. The phase lays the foundation for subsequent phases, such as system integration and verification, as well as safety validation.

It's important to note that the specific implementation and practices within this phase can vary depending on the complexity of the system, the automotive manufacturer, and the nature of the hardware components being developed.

5.7. ?Hardware Development V-Model

As we mentioned earlier the V-Model is a development approach that emphasizes the relationship between development phases and corresponding testing phases, highlighting the importance of verification and validation activities throughout the product development lifecycle.

In the Product Development at the Hardware Level phase, the V-Model can be applied as follows:

Requirements Phase:

• Development Activities: Specifications of hardware safety requirements are defined, including safety mechanisms, redundancy, and fail-safe features.
• Testing Activities: Verification activities include reviewing and assessing the hardware safety requirements to ensure they are accurately captured and well-defined.

Hardware Architectural Design Phase:

• Development Activities: The architecture of hardware components is designed, incorporating safety measures, fault tolerance, and redundancy.
• Testing Activities: Verification activities involve reviewing the architectural design to ensure that it aligns with safety goals and requirements, confirming that the architecture supports safety mechanisms.

Hardware Unit Design and Implementation Phase:

• Development Activities: Individual hardware units are designed and implemented with safety mechanisms, error handling, and redundancy as needed.
• Testing Activities: Verification includes testing the hardware units to ensure they function as intended and adhere to safety requirements.

Hardware Unit Verification Phase:

• Development Activities: Hardware units are tested, simulated, and analyzed to verify their functionality and safety.
• Testing Activities: Verification activities involve testing the hardware units to ensure they meet safety requirements and perform reliably.

Hardware Integration and Verification Phase:

• Development Activities: Hardware components are integrated into the overall system architecture.
• Testing Activities: Integration testing is performed to validate the interactions between different hardware components and ensure they work together as intended.

Evaluation of the Hardware Architectural Metrics Phase:

• Development Activities: Hardware architectural metrics are evaluated, such as diagnostic coverage and fault latency.
• Testing Activities: Verification activities involve assessing these metrics to ensure they meet safety goals and contribute to functional safety.

Evaluation of Safety Goal Violations Due to Random Hardware Failures Phase:

• Development Activities: The impact of random hardware failures on safety goals is evaluated.
• Testing Activities: Verification involves analyzing the effect of random hardware failures on the system's ability to achieve safety goals.

Testing of the Embedded Software Phase:

• Development Activities: Embedded software components are designed and developed to interact with hardware components.
• Testing Activities: Testing the embedded software includes verifying its interactions with hardware and ensuring correct communication and behavior.

The V-Model's structure represents the parallelism between the development and testing phases. The left side of the "V" signifies development, while the right side signifies corresponding testing phases. The point where the two sides of the "V" meet represents the integration and verification of hardware components, ensuring they function as intended and contribute to overall system safety.

Applying the V-Model in the Product Development at the Hardware Level phase helps ensure that safety aspects are systematically integrated into the hardware development process, allowing for early issue detection, risk reduction, and the creation of a safety-critical system that aligns with the standard.

?

6. Product Development at the Software Level

The Product Development at the Software Level phase of involves creating and validating the software components that constitute the safety-critical automotive system. This phase ensures that the software functions reliably, and adheres to safety requirements, and contributes to achieving the defined safety goals. The goal is to develop software that operates safely and effectively under various conditions.

Here's a detailed breakdown of the Product Development at the Software Level phase per ISO 26262, divided into sections along with examples for each subsection:

6.1. General Topics for the Product Development at the Software Level:

This section addresses general aspects related to software development for the safety-critical system.

Subsections:

• Development Interface Agreement: Define agreements and interfaces between software development teams and other disciplines.

Example: Ensuring collaboration and communication between software developers, hardware designers, and functional safety engineers for a brake control system.

• Responsibility and Authority: Assign responsibilities and authorities for various software development and safety aspects.

Example: Designating a lead software engineer responsible for overseeing software development activities and ensuring safety compliance.

6.2. Specifications of Software Safety Requirements:

This section involves specifying safety requirements for the software components of the system.

Subsections:

• Software Safety Requirements Allocation: Allocate safety requirements to specific software components and functions. Example: Allocating the reliable sensor data processing requirement to the adaptive cruise control algorithm.
• Software Safety Requirements Derivation: Derive specific software safety requirements from higher-level functional safety requirements. Example: Deriving a requirement for robust error handling in the engine control software from a functional safety requirement.

6.3. Software Architectural Design:

This section focuses on designing the architecture of software components to meet safety requirements.

Subsections:

• Software Architecture and Design: Design software architecture to ensure functional safety, including redundancy, fault tolerance, and fail-safe mechanisms. Example: Designing a redundant control algorithm for an autonomous emergency braking system to ensure accurate and reliable braking control.

6.4. Software Unit Design and Implementation:

This section involves designing and implementing individual software units.

Subsections:

• Software Unit Design: Design individual software units with safety mechanisms and error handling. Example: Designing a software unit that processes input from multiple sensors and selects the most reliable sensor data for use in a lane departure warning system.
• Software Unit Implementation: Implement software units focusing on adhering to safety requirements. Example: Implementing a software unit that integrates sensor data and decision-making logic to provide accurate steering inputs for lane-keeping.

6.5. Software Unit Verification:

This section focuses on verifying the individual software units for safety and functionality.

Subsections:

• Software Unit Verification Plan: Develop a plan for verifying the safety and functionality of software units. Example: Creating a plan for testing a software unit that processes camera data for detecting pedestrians in an autonomous pedestrian detection system.
• Software Unit Testing: Conduct tests on software units to ensure they function as intended. Example: Performing unit tests on a software module responsible for collision detection in an adaptive cruise control system.

6.6. Software Integration and Verification:

This section involves integrating software units and verifying their interaction.

Subsections:

• Software Integration: Integrate software units to ensure they interact correctly. Example: Integrating software units responsible for adaptive cruise control, lane departure warning, and collision avoidance to work seamlessly in an advanced driver assistance system.
• Software Integration Testing: Conduct integration tests to validate the interactions between different software units. Example: Testing the interaction between the brake control software and the electronic stability control software in a coordinated braking scenario.

6.7. Testing of the Embedded Software:

This section addresses comprehensive testing of the embedded software.

Subsections:

• Test Plan for Embedded Software: Develop a test plan for thoroughly testing the embedded software. Example: Creating a test plan that includes simulation, hardware-in-the-loop testing, and real-world testing for an autonomous parking system.
• Functional and Safety Testing: Conduct functional and safety testing to ensure the embedded software meets safety requirements. Example: Testing the embedded software of an autonomous emergency braking system to ensure it detects obstacles accurately and triggers timely braking actions.

?

The Product Development at the Software Level phase results in well-designed, verified, and integrated software components that contribute to the overall safety of the automotive system. These software components play a crucial role in achieving the system's safety goals and functional requirements. This phase sets the groundwork for subsequent phases, such as software integration, hardware-software integration, and the overall safety validation of the system.

It's important to note that software development practices can vary based on the complexity of the system, the manufacturer's approach, and the specific safety goals. ISO 26262 provides a structured framework to guide these activities and ensure that safety considerations are integral to the software development process.

Note:

1. If you are interested in seeing more detail on how software development phases are implemented, there is an article by Feabhas Ltd. Named “A quick guide to ISO 26262.” https://www.feabhas.com/sites/default/files/2016-06/A%20quick%20guide%20to%20ISO%2026262%5B1%5D_0_0.pdf

2. Another interesting site you may want to check is kuglermaag.com. They are consulting company helping others develop software procedures for automotive design. https://www.kuglermaag.com/automotive-spice/swe3-sw-detailed-design/

?

6.8. ?Software Development V-Model?

In the Product Development at the Software Level phase, the V-Model can be applied as follows:

Specifications of Software Safety Requirements Phase:

• Development Activities: Safety requirements for software components are defined, encompassing error handling, fail-safe mechanisms, and safety functions.
• Testing Activities: Verification involves reviewing and analyzing the software safety requirements to ensure they are accurately captured and properly specified.

Software Architectural Design Phase:

• Development Activities: The architecture of software components is designed, considering safety mechanisms, fault tolerance, and redundancy.
• Testing Activities: Verification activities include reviewing the architectural design to ensure that it aligns with safety goals and requirements, confirming that the architecture supports safety functions.

Software Unit Design and Implementation Phase:

• Development Activities: Individual software units are designed and implemented with safety mechanisms, error handling, and fail-safe behavior.
• Testing Activities: Verification includes testing the software units to ensure they function as intended and adhere to safety requirements.

Software Unit Verification Phase:

• Development Activities: Software units are tested, simulated, and analyzed to verify their functionality and safety.
• Testing Activities: Verification activities involve testing the software units to ensure they meet safety requirements and function reliably.

Software Integration and Verification Phase:

• Development Activities: Software components are integrated into the overall system architecture.
• Testing Activities: Integration testing is conducted to validate the interactions between different software components and ensure they work harmoniously.

Testing of the Embedded Software Phase:

• Development Activities: Embedded software components are developed to interact with other software and hardware components.
• Testing Activities: Verification includes testing the embedded software to ensure it interacts correctly with hardware and software, and performs its functions accurately.

Validation Phase:

• Development Activities: Safety validation is performed to demonstrate that the software meets the established safety goals and requirements.
• Testing Activities: Validation testing is conducted to verify that the software operates as expected in various scenarios, providing evidence of achieving safety goals.

The V-Model's structure illustrates the parallelism between development and testing phases. The left side of the "V" represents development, while the right side signifies corresponding testing phases. The point where the two sides of the "V" meet represents the integration and verification of software components, ensuring they function as intended and contribute to overall system safety.

6.9.? V-Model’s Cross-Functionality for System, Hardware and Software Development Phases

The cross-functional interaction between the V-Models is crucial for ensuring the overall safety, functionality, and compliance of a safety-critical automotive systems with ISO 26262 standards. The V-Models of each phase are interconnected to ensure a systematic approach to development, verification, and validation. Here's how they interact and why:

Interaction between V-Models:

1. System Level V-Model and Hardware Level V-Model:

• The System Level V-Model provides the high-level requirements and architectural design for the entire system, including the hardware components.
• The Hardware Level V-Model takes these high-level requirements and architectural designs to design, implement, and verify individual hardware units.
• Interaction: The Hardware Level V-Model ensures that the hardware components are designed and verified to meet the safety and functional requirements set by the System Level V-Model. For example, if the System Level V-Model specifies a need for redundancy in a safety-critical system, the Hardware Level V-Model will design and verify redundant hardware units to fulfill this requirement.

Example: Adaptive Cruise Control System

• System Level V-Model: Specifies the requirement for adaptive cruise control functionality and the need for collision detection.
• Hardware Level V-Model: Designs and verifies the sensors and processors responsible for detecting obstacles and controlling vehicle speed.
• Interaction: The adaptive cruise control software (Software Level V-Model) relies on accurate obstacle detection data from the sensors (Hardware Level V-Model) to determine when to adjust the vehicle speed for collision avoidance.2. System Level V-Model and Software Level V-Model:
• The System Level V-Model sets the overarching safety context and requirements for the entire system.
• The Software Level V-Model translates these system-level requirements into software-specific safety requirements and mechanisms.
• Interaction:? System Level V-Model defines high-level system requirements, functional safety concept, and architectural design of the entire safety-critical system. It focuses on capturing safety goals, hazard analysis, and defining system-wide safety mechanisms. The Software Level V-Model design takes input from the System Level V-Model, develops and verifies software components. It ensures that software units adhere to functional and safety requirements and are effectively integrated with hardware components.

Example: Lane Departure Warning System

• ?System Level V-Model: Specifies the requirement for a lane departure warning feature to prevent unintentional lane departures.
• ?Software Level V-Model: Designs and develops software units that process sensor data, analyze lane markings, and generate warnings.
• Interaction: The software units' design (Software Level V-Model) aligns with the system's requirement for accurate lane detection and timely warning generation (System Level V-Model).

1. Hardware Level V-Model and Software Level V-Model:

• The Hardware Level V-Model provides the hardware architecture and specifications required for the proper functioning of the software components.
• The Software Level V-Model designs, implements, and verifies software units that interact with the hardware components.
• Interaction: The Software Level V-Model ensures that the software units are developed and tested to interface correctly with the hardware units designed and verified in the Hardware Level V-Model. For example, if the Hardware Level V-Model specifies the communication interfaces and sensor data formats, the Software Level V-Model ensures that the software units can process this data accurately.

Example: Engine Control System

• Hardware Level V-Model: Designs and verifies the sensors, actuators, and microcontrollers responsible for controlling engine parameters.
• Software Level V-Model: Develops and tests software modules that process sensor data and send commands to actuators for optimal engine performance.
• Interaction: The software controlling engine parameters (Software Level V-Model) interacts with hardware components like sensors and actuators (Hardware Level V-Model) to ensure the engine operates safely and efficiently.

These interactions ensure a seamless flow of information, requirements, and design considerations across the different phases of development. The interconnected V-Models help identify potential issues early, promote collaboration between development teams, and ultimately lead to a well-integrated, safe, and compliant automotive system that meets the functional safety standards outlined in ISO 26262.

?

7. Production, Operation, Service, and Decommissioning

The production, Operation, Service, and Decommissioning phase, in accordance with ISO 26262, is divided into subsections:

7.1. Planning for Production, Operation, Service, and Decommissioning:

This section focuses on planning activities related to the production, operation, service, and eventual decommissioning of the safety-critical system.

Subsections:

• Production and Manufacturing Planning: Plan for the production process, including quality control, traceability, and adherence to safety requirements. Example: Planning the manufacturing of a vehicle's braking system to ensure consistent quality and safety through proper assembly and testing procedures.
• Operation and Maintenance Planning: Develop plans for the operational phase, including monitoring, maintenance, and updates. Example: Creating a maintenance schedule for an autonomous driving system that includes regular sensor calibration and software updates.

7.2. Production:

This section covers the actual production of hardware and software components while adhering to safety requirements and standards.

Subsections:

• Hardware Production: Manufacture hardware components in compliance with safety requirements and quality standards. Example: Manufacturing sensors for an airbag system, ensuring they are built with high accuracy to detect collisions and trigger airbag deployment.
• Software Production: Develop and test software components in a controlled environment, ensuring adherence to coding standards and functional safety.Example: Developing software modules responsible for handling emergency braking in an advanced driver assistance system.

7.3. Operation, Service, and Decommissioning:

This section addresses activities related to the operational phase, servicing, and eventual decommissioning of the safety-critical system.

Subsections:

• Operation and Monitoring: Ensure that the system operates within safety limits and monitor its behavior during real-world usage. Example: Monitoring the behavior of a vehicle's stability control system during different driving conditions to ensure it intervenes only when necessary.
• Servicing and Maintenance: Conduct regular maintenance, updates, and repairs to ensure the system's continued safe operation. Example: Performing software updates on an electric vehicle's battery management system to optimize battery performance and safety.
• Decommissioning and End of Life: Plan for the system's end-of-life phase, including the safe disposal of components and data. Example: Properly disposing of safety-critical components from decommissioned vehicles, ensuring they don't pose environmental or safety hazards.

The Production, Operation, Service, and Decommissioning phase ensures that the safety-critical system's lifecycle is managed beyond its development, considering aspects like manufacturing quality, ongoing monitoring, maintenance, and responsible end-of-life practices. It's important to note that the specific implementation of this phase can vary based on the complexity of the system, the manufacturer's practices, and the regulatory requirements in the automotive industry. ISO 26262 provides a framework to guide these activities and ensure that safety considerations continue to be addressed throughout the system's operational lifespan.

?

8. Supporting Processes

The Supporting Processes phase in ISO 26262 encompasses various essential processes crucial for managing the development of safety-critical systems.

Let's break down this phase into sections and provide examples for each subsection:

8.1. Interfaces within Distributed Developments:

This section deals with managing interfaces and collaborations between different teams or entities involved in developing safety-critical systems.

Subsections:

• Team Collaboration: Ensure effective communication and collaboration between distributed development teams.Example: Coordinating vehicle control software development between teams in different countries to ensure consistency and compliance with safety standards.

8.2. Specification and Management of Safety Requirements:

This section focuses on specifying and managing safety-related requirements throughout the development lifecycle.

Subsections:

• Safety Requirement Specification: Clearly define safety requirements related to the system's behavior under various conditions.Example: Specifying safety requirements for an autonomous driving system, including response times for collision avoidance.
• Safety Requirement Management: Implement a system for managing and tracking safety requirements throughout the development process. Example: Using a requirement management tool to track and update safety requirements as they evolve during the development of an airbag system.

8.3. Configuration Management:

This section addresses the management of configuration items, changes, and version control.

Subsections:

• Configuration Item Identification: Identify and classify all configuration items, including hardware, software, and documentation.Example: Identifying and labeling different control software versions for a brake system.
• Configuration Change Management: Establish procedures for reviewing, approving, and implementing changes to configuration items. Example: Implementing a change control board to evaluate and approve changes to the hardware design of a powertrain control unit.

8.4. Change Management:

Change management processes focus on handling changes to the safety-critical system throughout its lifecycle.

Subsections:

• Change Control Process: Define processes for assessing, documenting, and managing changes to the system.Example: Implementing a change management process to assess and approve software updates for a collision avoidance system.

8.5. Verification:

Verification processes ensure that the developed components meet the specified requirements and safety goals.

Subsections:

• Verification Planning: Develop a plan for conducting verification activities, including testing and analysis.Example: Creating a verification plan that outlines the testing procedures and criteria for verifying the reliability of a seatbelt tensioning system.

8.6. Documentation Management:

This section addresses the management and maintenance of all documentation related to the development process.

Subsections:

• Document Control: Establish procedures for document creation, revision, and storage.Example: Implementing a document control system to ensure that all safety-related documents are up-to-date and easily accessible.

8.7. Confidence in the Use of Software Tools:

This section ensures that software tools used in the development process are reliable and do not introduce safety risks.

Subsections:

• Software Tool Qualification: Qualify and validate software tools used in safety-critical development.Example: Qualifying a static code analysis tool to ensure it accurately identifies potential software defects in an engine control unit.

8.8. Qualification of Software Components:

This section addresses the qualification of software components that are critical to safety.

Subsections:

• Software Component Qualification: Qualify and validate software components essential for safety functions.Example: Qualifying the software component responsible for airbag deployment to ensure it reliably detects collisions and deploys airbags when needed.

8.9. Evaluation of Hardware Elements:

This section focuses on evaluating and ensuring the reliability of hardware elements used in the system.

Subsections:

• Hardware Element Evaluation: Assess the reliability and performance of hardware components, such as sensors and controllers.Example: Evaluating the reliability of a radar sensor used in an adaptive cruise control system to detect and track nearby vehicles.

8.10. Proven In-Use Argument:

This section involves building arguments based on real-world usage data to demonstrate the safety and reliability of the system.

Subsections:

• In-Use Data Collection: Collect and analyze data from systems in real-world operation to prove their safety and reliability.Example: Collecting and analyzing data from a fleet of autonomous vehicles to demonstrate the safety and effectiveness of their collision avoidance systems.

8.11. Interfacing an Application that is out of the scope of ISO 26262:

This section addresses the integration of applications or components that are not covered by ISO 26262 but are necessary for the system's overall functionality.

Subsections:

• Integration Planning: Develop a plan for integrating non-safety-critical components or applications.Example: Planning the integration of an infotainment system (not covered by ISO 26262) into a vehicle's overall electronics architecture while ensuring it does not compromise safety-critical functions.

8.12. Integration of Safety-Related Systems not developed according to ISO 26262:

This section deals with integrating safety-related systems not originally developed according to ISO 26262.

Subsections:

• Integration Strategy: Develop a strategy for integrating external safety-related systems while ensuring they meet safety requirements.Example: Integrating a third-party collision detection system into a vehicle's safety architecture and ensuring it complies with ISO 26262 safety standards.

The Supporting Processes phase plays a critical role in ensuring that the development of safety-critical systems is well-organized, documented, and compliant with ISO 26262 standards. These processes help manage complexity, track changes, and build confidence in the safety and reliability of the final product.

?

9. Automotive Safety Integrity Level (ASIL) Oriented and Safety-Oriented Analyses

The Automotive Safety Integrity Level (ASIL) Oriented and Safety-Oriented Analyses phase determines the appropriate safety measures and achieves the desired ASIL for safety-critical automotive systems.?

Let's break down this phase into sections and provide examples for each subsection:

9.1. Requirements Decomposition with Respect to ASIL Tailoring:

This section focuses on breaking down system-level requirements into lower-level requirements while considering ASIL tailoring.

Subsections:

• ASIL Allocation: Allocate ASILs to system functions and components based on their safety relevance.Example 1: Allocating ASIL D to the collision avoidance system, as a failure in this system could lead to severe consequences.Example 2: Allocating ASIL A to the infotainment system, as its failure is unlikely to cause severe harm.
• ASIL Tailoring: Modify or tailor requirements based on the allocated ASIL, considering safety goals and risk reduction measures. Example 1: Increasing the diagnostic coverage and fault tolerance requirements for a brake-by-wire system allocated with ASIL D. Example 2: Reducing the diagnostic coverage requirements for non-safety-critical infotainment features allocated with ASIL QM (Quality Management).

9.2. Criteria for Coexistence of Elements:

This section addresses the criteria for ensuring that safety-critical elements coexist without compromising safety.

Subsections:

• Element Coexistence Criteria: Define criteria for elements to coexist safely, including shared resources and interfaces.Example 1: Defining communication protocols and arbitration rules to ensure multiple safety-critical electronic control units (ECUs) can share the same communication bus without conflicts.Example 2: Specifying hardware isolation requirements for two safety-critical systems with the same power supply to prevent interference.
• Isolation Mechanisms: Specify mechanisms for isolating safety-critical elements to prevent unintended interactions. Example 1: Implementing hardware-based isolation between the engine control unit and the infotainment system to prevent potential interference. Example 2: Using software-based firewalls and access controls to isolate safety-critical functions from non-safety-critical functions within a vehicle's network.

9.3. Analysis of Dependent Failures:

This section analyzes failures that could occur in multiple elements or subsystems and their potential impact on system safety.

Subsections:

• Dependent Failure Analysis: Identify potential dependencies and interactions between elements that could lead to failures.Example 1: Analyzing the potential impact of a common power supply failure on multiple safety-critical ECUs and implementing mitigation strategies.Example 2: Assessing the risks of simultaneous sensor failures in an autonomous driving system and developing fallback mechanisms.
• Mitigation Measures: Develop mitigation measures to reduce the risk of dependent failures and their consequences. Example 1: Implementing diversity in sensor types and redundant sensor voting algorithms to minimize the risk of simultaneous sensor failures in an adaptive cruise control system. Example 2: Designing hardware and software watchdog mechanisms to detect and recover from software failures in a drive-by-wire system.

9.4. Safety Analyses:

This section involves conducting safety analyses to assess the system's compliance with ASIL requirements and identify potential safety issues.

Subsections:

• Hazard Analysis and Risk Assessment (HARA): Perform HARA to identify hazards, assess their risk, and assign ASILs to safety goals.Example 1: Conducting HARA to identify the hazard of unintended acceleration and assigning an ASIL C to the safety goal of preventing unintended acceleration.Example 2: Identifying the hazard of lane departure and assigning an ASIL B to the safety goal of lane-keeping assistance.
• Fault Tree Analysis (FTA): Use FTA to analyze the potential combinations of faults that could lead to hazardous events. Example 1: Using FTA to analyze how multiple sensor failures, such as radar and camera, can lead to a failure in a collision avoidance system. Example 2: Assessing the fault tree for a brake-by-wire system to determine the likelihood of losing braking capability due to multiple faults.

The "ASIL Oriented and Safety-Oriented Analyses" phase is critical for systematically assessing the safety aspects of a system, allocating ASILs appropriately, and identifying and mitigating potential safety risks.

?

10. Guidelines on ISO 26262

ISO 26262 includes a set of annexes and informative sections that offer additional guidance on various topics related to functional safety. These sections provide explanations, examples, and recommendations to help organizations interpret and apply the standard effectively.

These annexes and informative sections cover a wide range of topics, including:

10.1?? Guidelines for Hazard Analysis and Risk Assessment (HARA):

This section offers guidance on how to conduct hazard analysis and risk assessment, including techniques for identifying hazards, assessing their risk, and assigning Automotive Safety Integrity Levels (ASILs).

Example 1: Hazard Identification

The HARA process identifies hazards associated with a lane-keeping assist system. One identified hazard is "Inadequate lane detection," where the system fails to recognize faded lane markings on the road.

Example 2: Risk Assessment and ASIL Assignment

After assessing the risk associated with the "Inadequate lane detection" hazard, it is assigned an ASIL B because the risk is high, but there are mitigations in place to reduce the severity of consequences.

10.2?? Guidelines for Functional Safety Management:

This section provides recommendations for establishing and maintaining a functional safety management system, including organizational roles and responsibilities, safety culture, and safety management processes.

Example 1: Safety Culture

The guidelines emphasize fostering a safety culture within the organization. An example of this is establishing regular safety awareness training for all employees to instill a safety-conscious mindset.

Example 2: Safety Management Processes

The guidelines recommend implementing a safety management process that includes regular safety reviews and audits to ensure compliance with ISO 26262 requirements.

10.3? Guidelines on Safety Lifecycle Traceability:

This section explains the importance of traceability in demonstrating compliance with ISO 26262 requirements and provides guidance on how to establish and maintain traceability throughout the safety lifecycle.

Example 1: Requirements Traceability

To demonstrate traceability, the guidelines suggest creating a traceability matrix that links each safety requirement to the corresponding design element, verification activity, and validation test case.

Example 2: Change Management Traceability

The guidelines recommend maintaining traceability during change management by updating the traceability matrix when requirements are modified to reflect the changes accurately.

10.4?? Guidelines on Safety-Oriented Analyses:

This section offers guidance on safety analyses techniques, such as fault tree analysis (FTA), failure mode and effects analysis (FMEA), and common cause analysis.

Example 1: Fault Tree Analysis (FTA)

In FTA, the guidelines explain how to construct a fault tree to analyze a hazardous event, such as "Loss of steering control." The tree breaks down the event into contributing fault scenarios, considering components like sensors, actuators, and software.

Example 2: Failure Mode and Effects Analysis (FMEA)

The guidelines provide a step-by-step process for conducting FMEA on a brake system. The analysis identifies failure modes (e.g., "Brake fluid leak"), assesses their effects, assigns risk priority numbers, and recommends mitigation actions.

10.5?? Guidelines for Software Development:

This section provides recommendations for the development of safety-critical software, including software architectural design, coding standards, and software verification and validation.

Example 1: Software Architecture Design

The guidelines describe how to design software architecture for an airbag deployment system, highlighting the importance of redundancy and error-handling mechanisms to ensure safe deployment.

Example 2: Coding Standards

The guidelines recommend using specific coding standards (e.g., MISRA C) for safety-critical software development, outlining rules for secure coding practices.

10.6?? Guidelines on Hardware Development:

This section offers guidance on hardware development processes, including design considerations, safety mechanisms, and hardware verification and validation.

Example 1: Hardware Safety Mechanisms

The guidelines explain the use of hardware safety mechanisms, such as dual-redundant microcontrollers in a drive-by-wire system, to ensure functional safety even in the presence of hardware faults.

Example 2: Hardware Verification and Validation

The guidelines provide examples of hardware testing procedures, such as fault injection testing, to validate hardware safety mechanisms and assess their effectiveness.

10.7?? Guidelines on Supporting Processes:

This section provides guidance on supporting processes such as configuration management, change management, documentation management, and more.

Example 1: Configuration Management

The guidelines outline the process for managing hardware and software configurations, including version control, release management, and change tracking for safety-critical components.

Example 2: Documentation Management

The guidelines recommend maintaining a comprehensive document control system that includes versioning, access control, and archiving of safety-related documents.

10.8 ??Guidelines on Verification and Validation:

This section offers recommendations for verification and validation activities, including testing, analysis, and assessment of safety-related components.

Example 1: Verification Testing

The guidelines provide a sample test plan for verifying a backup camera system's compliance with safety requirements, including test cases for image quality, latency, and error handling.

Example 2: Validation Testing

The guidelines describe the validation testing of an autonomous parking system using real-world scenarios to assess its performance under various conditions.

10.9 ??Guidelines on ASIL Tailoring:

This section provides guidance on how to tailor ASIL requirements to specific applications and components within a system.

Example 1: Reducing Diagnostic Coverage

The guidelines explain how to tailor ASIL requirements by reducing the required diagnostic coverage for non-safety-critical infotainment features (ASIL QM) to a lower level than safety-critical systems.

Example 2: Increasing Safety Goals

The guidelines suggest increasing safety goals, such as fault tolerance, for a steer-by-wire system allocated with ASIL D to ensure a higher level of safety.

Table below shows an example of ASIL Ranking Table:

?10.10 ??Guidelines on Safety Verification of Hardware Elements:

This section outlines methods and techniques for verifying the safety of hardware elements within a safety-critical system.

Example 1: Hardware Testing

The guidelines describe methods for testing hardware elements like automotive sensors, including environmental testing (e.g., temperature and humidity) and functional testing (e.g., signal accuracy).

Example 2: Redundancy Analysis

The guidelines provide techniques for analyzing the redundancy of safety-critical hardware elements, such as electronic control units (ECUs), to ensure that they meet the required safety goals.

?

These annexes and informative sections are designed to complement the main body of ISO 26262 and assist organizations in understanding and implementing the standard's requirements effectively. They provide practical insights and examples to support the development of safe and reliable automotive systems.

?

11. Guidelines on application of ISO 26262 to semiconductors

ISO 26262 includes guidelines for applying the standard to semiconductors, recognizing their crucial role in safety-critical automotive systems. Below, I'll provide two examples for each of the main sections and subsections related to the guidelines for the application of ISO 26262 to semiconductors:

A. Introduction to Semiconductors

A.1. General

This subsection sets the stage by explaining that ISO 26262 provides guidelines for semiconductors used in safety-critical automotive systems. It clarifies the role of semiconductors in ensuring the safety and reliability of these systems.

• Example 1: Integrated Safety Controller (ISC)

When designing an ISC for a vehicle's electronic stability control system, the semiconductor manufacturer follows ISO 26262 guidelines for semiconductor development to ensure that the ISC functions reliably under all driving conditions.

• Example 2: Advanced Driver Assistance System (ADAS)

A semiconductor company develops a microcontroller unit (MCU) for an ADAS application, adhering to ISO 26262 semiconductor guidelines to guarantee that the MCU's processing of sensor data and control outputs meets safety requirements.

A.2. Purpose

This subsection defines the scope of ISO 26262 for semiconductors, outlining which semiconductor components and applications fall under its purview. It helps semiconductor manufacturers understand when compliance is necessary.

• Example 1: Airbag Control Unit

A semiconductor manufacturer creates a safety manual for an airbag control unit, explicitly stating its purpose, intended use, and adherence to ISO 26262 for functional safety, providing essential information to automotive OEMs and Tier 1 suppliers.

• Example 2: Camera Sensor

A sensor manufacturer produces a camera sensor designed for lane departure warning systems, clearly outlining its purpose in enabling safety functions and conforming to ISO 26262 semiconductor guidelines to ensure safety.

A.3. Scope

This subsection further emphasizes the scope of the standard for semiconductor development and production phases, making it clear which stages of development and production are covered by ISO 26262.

• Example 1: Automotive Radar Chip

A semiconductor company specifies that their automotive radar chip, which detects objects around the vehicle, falls within the scope of ISO 26262, and it is developed according to the standard's requirements.

• Example 2: Electronic Control Unit (ECU)

A manufacturer of ECUs for vehicle engine control includes in its documentation that the ECUs are subject to ISO 26262 semiconductor guidelines due to their role in ensuring safe engine operation.

B. Reference Model

B.1. Overview

This subsection provides an overview of the reference model for ISO 26262-compliant semiconductors. It acts as a foundational concept that semiconductor manufacturers can use to structure their development and production processes.

• Example 1: ISO 26262 Compliant Semiconductors

An industry association defines a reference model for ISO 26262-compliant semiconductors, which semiconductor manufacturers use as a foundation for developing safety-critical chips.

• Example 2: Functional Safety Manager

A semiconductor company designates a functional safety manager responsible for overseeing the development of semiconductor components, aligning with the reference model outlined in ISO 26262.

B.2. Semiconductor Development and Production Phases

This subsection outlines the phases involved in semiconductor development and production. It ensures that semiconductor manufacturers follow a structured approach aligned with ISO 26262's expectations.

• Example 1: Development of Safety-Critical ASIC

A semiconductor firm follows the semiconductor development and production phases defined in ISO 26262 when creating a custom application-specific integrated circuit (ASIC) for a brake-by-wire system.

• Example 2: FPGA for Autonomous Vehicle Control

A manufacturer of field-programmable gate arrays (FPGAs) outlines the semiconductor development phases in ISO 26262 for an FPGA used in autonomous vehicle control systems.

B.3. Interface to Other ISO 26262 Development Phases

This subsection focuses on the interfaces between semiconductor development and other ISO 26262 development phases, emphasizing the importance of ensuring compatibility and safety throughout the development process.

• Example 1: Software-Hardware Interface

A semiconductor manufacturer ensures that the interfaces between its semiconductor components and software components in safety-critical systems adhere to ISO 26262 requirements to facilitate integration.

• Example 2: Sensor Integration

A sensor manufacturer documents the interfaces between their sensors and control units in compliance with ISO 26262, ensuring that the sensor can be integrated safely into various automotive systems.

C. Requirements

C.1. Overview

This subsection introduces the concept of requirements for ISO 26262-compliant semiconductor components. It highlights the necessity of setting safety goals, implementing safety mechanisms, and maintaining proper documentation.

• Example 1: ISO 26262-Compliant Semiconductor Components

A semiconductor company defines a set of requirements for ISO 26262-compliant semiconductor components, specifying functional safety goals, safety mechanisms, and documentation standards.

• Example 2: Safety-Related Data Storage

A flash memory manufacturer outlines requirements for safe data storage in automotive applications, conforming to ISO 26262's guidelines for semiconductor components.

C.2. Development of Semiconductors

This subsection delves into the requirements related to the development of semiconductor components. It addresses elements such as development plans and hardware safety requirements, which are crucial for ensuring semiconductor safety.

• Example 1: Semiconductor Development Plan

A semiconductor developer creates a development plan for a safety-critical chip, encompassing ISO 26262 requirements, including validation and verification activities.

• Example 2: Hardware Safety Requirements

A semiconductor firm establishes hardware safety requirements for their microcontrollers, ensuring compliance with ISO 26262's semiconductor development guidelines.

C.3. Production of Semiconductors

This subsection focuses on requirements during the production of semiconductor components. It highlights the significance of manufacturing quality control and traceability to minimize the risk of defects and ensure product reliability.

• Example 1: Manufacturing Quality Control

A semiconductor manufacturer implements rigorous quality control measures during chip production, conforming to ISO 26262 requirements to minimize the risk of manufacturing defects.

• Example 2: Traceability in Semiconductor Production

A semiconductor foundry maintains traceability records for each semiconductor component produced, enabling the identification and tracking of individual chips throughout their lifecycle as per ISO 26262.

These sections and subsections within the guidelines for applying ISO 26262 to semiconductors provide a structured framework for semiconductor manufacturers to follow when developing and producing components for safety-critical automotive systems. They help ensure that semiconductors meet the safety and reliability standards necessary to safeguard vehicle occupants and road users.

?