functional safety

While building SLIKWORKS, we used AI to automate much of the safety analysis work. Along the way, we encountered a number of challenges in applying LLMs and other ML models to this domain. These challenges are described in more detail in our SAE publication - AI-Powered FMEA in the Safety-Critical Industry. Below, we outline some of the key challenges we faced. Fig: AI tool challenges in mission-critical systems Hallucinations in LLMs Hallucinations in LLMs refer to instances

In the previous blog post, we looked at the different layers of an operating scenario. In this blog post, we will look at the different abstraction levels, and why it matters for ISO 26262 HARA and SOTIF HARA. The Three Abstraction Levels of Operating Scenarios Each operating scenario can be described in 6 layers as described in the the previous blog post. In addition, each operating scenario can be described in 3 different abstraction levels. Functional scenarios - They are

Why Scenarios Need a Format You cannot test an automated driving function against "traffic." The real world offers an effectively infinite set of situations: every combination of road layout, weather, other vehicles, and split-second timing is its own test case. Scenario-based safety is the industry's answer to that problem, but it only works if scenarios are described in a structured, repeatable way. Without a common format, one engineer's "car cuts in ahead" is another's "a

In the previous blog post, we talked about what a SOTIF HARA is and what is the process to create one. This this blog post we talk about acceptance criteria for SOTIF. Acceptance Criteria: The New Discipline If "unreasonable risk" is the question, Acceptance Criteria (AC) is what makes the answer defensible. AC is the quantified definition of acceptable: a measurable threshold the system must demonstrably meet before its residual risk can be called reasonable. This is what se

Hazards that are not due to malfunctions Classical functional safety assumes something "failed". A sensor failed, a wire shorted, a software routine crashed. ISO 26262 is built around this idea: identify the malfunctions, judge how bad they'd be, and engineer against them. But consider a perception system that saw the road exactly as designed and still failed to recognize a stationary truck in dense fog. Nothing malfunctioned. Every component behaved to specification. The sys

In the previous blog post, we talked about the theory behind the FTA. In this post, we are going to do a concrete example of an FTA A quick example: "Vehicle does not steer" To see how the pieces fit together, take a safety-critical top event from an automated vehicle: the vehicle does not steer. Loss of steering can happen in several independent ways, so directly beneath the top event sits an OR gate: any one branch alone is enough to cause it. Fig: FTA example The first bra

Before a passenger jet, a nuclear reactor, or a car's braking system is ever trusted with human lives, engineers sit down and ask a simple question: what would have to go wrong for this to fail catastrophically? Not "will it fail," but "what exact combination of smaller faults would it take." Answering that question rigorously is the job of Fault Tree Analysis (FTA), one of the most widely used safety and reliability techniques in engineering. What is an FTA ? Fault Tree Anal

HAZOP (Hazard and Operability Study) was originally developed for the chemical process industry, where facilities routinely handle hazardous materials. In such environments, even small malfunctions in manufacturing processes can lead to serious safety incidents. The methodology was first developed in 1961 as a structured way to systematically identify hazards and operability issues in complex industrial processes. Over time, the approach matured and was formally standardized

The previous blog post examined how memory management deficiencies can lead to safety hazards in mission-critical systems . This article focuses on methods and design practices that help prevent or mitigate such failures. How to solve memory issues? Practical defenses that work Memory safety isn’t solved by one magic tool or one “best practice.” In mission-critical embedded systems, the reliable approach is layered defense: good design choices first, then disciplined coding,

Functional Safety analyses using an FMEDA

One of the key objectives of ISO 26262 Part 5 is the evaluation of hardware architecture metrics to assess the robustness of an electrical/electronic (E/E) system against random hardware failures. This evaluation is performed using three core metrics: PMHF - Probabilistic Metric of Hardware Failure SPFM - Single Point Fault Metric LFM - Latent Fault Metric Together, these hardware architecture metrics provide a quantitative basis for assessing the final E/E hardware design b

During the development of mission-critical systems, safety risks emerge at different stages of the system lifecycle. No single safety analysis can address all of these risks. Instead, an effective safety strategy relies on a combination of safety analyses. The selection of appropriate analyses depends on the stage of the project, the information available at that point, and the types of issues or failure mechanisms that need to be identified. Some of the most common analyses

How memory management can turn into real safety hazards In mission-critical embedded systems, think automotive ECUs, avionics controllers, medical devices, industrial safety PLCs, memory safety is not a “nice-to-have.” It’s a reliability and safety requirement. A single memory bug can cause a watchdog reset, corrupt sensor readings, flip a state machine into the wrong mode, or silently degrade behavior over time. In safety terms, that means a software defect can become a ha

What are Embedded Systems? Before diving into Python's role, let's establish what embedded systems actually are. An embedded system is a specialized computer designed to perform specific tasks within a larger system. Unlike your laptop or smartphone, which runs many different applications, an embedded system typically does one job and does it reliably for years. You'll find embedded systems everywhere: in your car's braking system, your microwave, medical devices, and industr

Why do we need modern tools for functional safety? Product development in safety-critical industries such as automotive, aerospace, and robotics is no longer confined to a single team or location. Engineers, developers, and safety experts often work across different countries, time zones, and organizations. As of early 2025, safety engineering work has shifted to one that is increasingly hybrid, where 52% of such employees are working in a hybrid/remote manner. To function e

In everyday life, we rely on countless machines in our office, shopping centers, and even the machines in our homes. When these machines malfunction, they can lead to safety hazards. That’s why they are designed with functional safety in mind: to ensure that if something goes wrong, the machine either fails safely or continues operating in a safe state. Here are a few examples of functional safety we encounter every day: Functional Safety of an Elevator system Elevators are o

Powertrain in Electric Vehicles In this example, we’ll look at how functional safety applies to the powertrain system of an electric vehicle (EV), providing a practical view of how ISO 26262 can be implemented. In an EV, the High voltage battery pack supplies electrical power to the electric motor when the driver requests movement through the accelerator pedal. As the driver presses the pedal, sensors detect its position and send this information to a centralized computer, w

What is ISO 26262? ISO 26262 is an international standard for the functional safety of electrical and electronic (E/E) systems in road vehicles. It ensures that E/E systems in road vehicle - cars, trucks, and motorcycles remain safe even when faults occur. The standard defines a risk-based approach using Automotive Safety Integrity Levels (ASILs) to classify hazards, evaluate the risk of hazards, and methods to mitigate risks - from concept and design to production, operation

How to choose functional safety standards for a product? To ensure that a product is free from unreasonable safety-related risks, it is recommended to develop it in compliance with state-of-the-art safety standards. However, with numerous standards available, adhering to all of them is neither practical nor necessary. Instead, it is important to identify and adopt the most relevant standards based on the product’s intended application. The applicable functional safety stan