Automotive safety problems have been in the news recently. From Toyota's unintended acceleration issues, to GM's ignition switch recall, the general public may be wondering if anyone tests cars for safety. Of course the auto makers and their suppliers do extensively test their products for safety and reliability, although those tests may not always be enough.
Because electronics keep replacing mechanical systems in vehicles, testing has become more complex, requiring automation. To gain some insight into automated safety testing of cars and trucks, I spoke with Noah Reding, NI's Automotive and Aerospace Product Manager and Kyle Perkuhn, NI's Real-Time Test Product Marketing Engineer.
Test hardware can operate in a vehicle by measuring data from sensors and communicating with automotive electronic systems.
Martin Rowe: What is the current state of automotive safety testing?
Noah Reding: Because of the increased electronic content in today's vehicles, automotive parts makers must test for safety more than ever before. They tell us that they must assess the risk of failure of an embedded control system and test for that risk.
Martin Rowe: How is automotive safety testing evolving?
Noah Reding: For the past five or six years, there's been an effort to create an automotive functional-safety test standard, now known as ISO 26262. It's intended to make sure that anyone designing electronics intended to go inside a car will keep safety in mind. ISO 26262 outlines ways to assess the risk to the manufacturer and end-user should a component fail. It also outlines how to design, develop, and test to meet safety requirements.
Safety standards have been in place for years, often in the military and aerospace industries and they're now coming to the automotive industry. We've been able to take our experience from our mil/aero customers and apply that to help automotive customers.
Martin Rowe: What are the differences between the mil/aero safety requirements and those in automotive?
Noah Reding: All mil/aero designs must be tested to functional safety standards before a device can be installed in a aircraft. It's different with automotive. Manufacturers don't have to go through the same government functional safety testing requirements to get their products ISO 26262 certified. Given the recent Toyota and GM cases, we all know how lawyers will treat that. Knowing that a functional safety testing standard exists means that lawyers will exploit a standard and how it's used.
Martin Rowe: What do you explain to customers about functional safety testing?
Noah Reding: ISO 26262 states that any tool that can be used to test for functional safety needs to be qualified. In other words, how do you know that the test tool does what the manufacturer says it does? Can you trust the results that the tool provides? To get there, we've worked with a partner to develop a qualification kit that can be used with the TestStand, an automated test sequencer. It can be used to qualify automated tests for prototyping, HIL (hardware in the loop), or production testing. The kit lets engineers verify that a test tool does what users believe it does by providing documentation that a certification body would be interested in seeing.
Hardware-in-the-loop testing takes place where an automotive subsystem is connected to a test system, which provides simulated inputs and captures outputs from the subsystem under test.
To Page 2: Qualification and sharing