The Foundation of Good Functional Safety Work Products
Safety has been a part of the automotive industry since the vehicle was first introduced, but it’s never been more complex than it is today. The first significant advancements in safety technology were introduced in the 1950s. Since then, the tools and technology used to keep the driver, passengers, and others on the road safe has evolved, but the underlying objective has remained – to reduce the number of deaths and injuries related to car crashes.
Today’s vehicles are increasingly more sophisticated with advanced AI features and new electrified powertrains – a modern car has approximately 100 million lines of software code and that number is expected to jump to 300 million by 2030. This software complexity and the introduction of advanced features and benefits introduces a new level of safety to the automotive industry – functional safety.
Functional safety is part of the overall safety of a system or piece of equipment that depends on automatic protection. This automatic protection system needs to respond correctly to its inputs. And it should have predictable responses to failure. This includes human errors, hardware failures and operational/environmental stress.
Ensuring a vehicle’s safety is a complex job which requires knowledge, attentiveness and specificity.
The automotive industry has many safety standards. And while activities necessary to document and evaluate risks are similar, each one requires varying levels of effort. In addition, each lays out a process, which defines various types of measures to identify areas of potential risk, possible outcomes, and mitigations where the risk may present itself.
A company’s functional safety goal has two aspects. First, is developing a series of requirements that mitigate any unreasonable risk. And second is verifying the completeness of the requirement’s data set against the types of analysis and reviews required or performed for a specific product or system.
There are several principles focused on developing safety work products that can assist in achieving this goal.
Eliminate Uncertainty
When developing safety work products and requirements, it’s critical to eliminate any ambiguity within the documents. As safety engineers work through a project, they become acclimated to it, which can result in unintended consequences in their work. As a result, they can unknowingly attribute assumptions or expectations that are not properly defined or documented. To address this, a company can task new safety team members with reviewing existing work products because they can provide unfiltered insight.
See the Complete Picture
Safety work products and analysis need to be a complete story, starting with a beginning followed by an uninterrupted straight line to the end. A user needs to be able to review the work and walk away with a complete, clear understanding of the story. If they have questions, the document’s completeness needs to be reconsidered. It’s not uncommon to get the same question from multiple reviewers – this is a clear indication that the documentation is lacking and needs to be updated.
Clarity is Key
Safety work products are used to make critical decisions in a program. Ensuring documents related to the work can be properly understood results in a properly and thoroughly informed user. This level of attentiveness is especially critical when older work products may be reviewed due to ongoing use/reuse or an issue.
Defined, Consistent Language
Safety engineers need to rely on the terms, definitions, acronyms and abbreviations specific to the standard being supported. When working with ISO26262 or ISO21488 an “Item” has a single meaning and is therefore only used in a way specific its definition in the standard. For example, one standard may refer to a “vehicle” while another refers to a “machine.” Consistently using the correct term in safety work products minimizes any confusion the user may experience, especially as they review numerous work products. These terms need to be clearly defined within the work products or specifically reference the definition’s location. In addition, all referenced information must include the correct file and release level used in the document’s development. Similarly, the use of subjective terms (e.g., problem, bad, critical) must be avoided as they can be interpreted differently by individual users.
Precision… Precision… Precision…
For safety engineers, specificity and preciseness are critical, especially to a program’s success. It is important that this is understood through the team and integrated as a mindset into team member and all programs. Safety isn’t something to take lightly, especially in automotive.
FEV and Functional Safety
FEV has extensive experience in functional safety – thoroughly understanding and applying the various standards; item definition; safety analyses, verification and validation; development of concepts; and consulting. We even have an approach for demonstrator or prototype vehicles that do not have an applicable safety standard. Our functional safety experts work hand-in-hand with topical technical experts who specify, implement and test the safety requirements defined by FEV. For more information on our functional safety capabilities, contact us at fusa@fev.com.