The Automotive V-Cycle

Carmakers embrace a rigorous verification methodology.


During the research for my article on making cars smarter, I learned from Andrew Patterson at Mentor Graphics that when it comes to the verification side, one well-established practice in the automotive industry is the use of the V-Cycle design methodology (also known as the V-Model) and that carmakers tend to follow that.

He explained that the idea behind the V-Cycle is that the two arms of the V include design, validation and test and you can go around that loop. “Then, and as the thing becomes more real, you validate it each step of the way. Carmakers are using Hardware-In-The-Loop, Software-In-The-Loop techniques so they may not have their whole network complete but they may have done two or three of the ECUs and have real hardware examples for them — but the rest is still a software model.”

There are tools that can link those bits together so the hardware model can be linked with the software models and validated in situ the partially complete design. “Doing that verification as you go through step by step helps to save time and save risk,” Patterson stressed. “If you wait until you got to the end of the process, and suddenly bolt together 50 ECUs, there’s a good chance something will be wrong. If you validate each step with a software model round it, you’ve got incremental confidence that the whole thing’s going to work.”

Interestingly, Mentor figures there are 130 car models on the road with its ECU software running in them.