Cars are going through some fundamental changes. Not only is the amount of electronics in a car dramatically increasing, but the design approaches used for system-on-chip devices are now being adopted for the cars themselves, and for the systems that include cars. Which means car makers moving to system level design tools.
Tool makers are starting to pay attention, with major sessions on the tools and requirements for automotive design at this year’s Design Automation Conference (DAC).
“We really have the opportunity to create a new DNA for automobiles,” says Lawrence Burns, v-p of R&D and strategic planning at General Motors (GM). “There’s an enormous opportunity to accelerate the growth of the auto industry in a truly sustainable way. We are talking about a transformation that is every bit as dramatic as the transition from horse power.”
“It really is the land of opportunity for EDA because automotive electronic design is at a similar stage to where IC design was in the 1970s,” says Wally Rhines, CEO of Mentor Graphics.
“OEMs want to simulate the whole car in a server farm, with each electronic control unit mapped to a processor in that farm,” says Alain Labat, CEO of VaST Systems. “It’s a development and research issue. The challenge is the debug environment - pulling the data out.”
As one of the world’s largest car manufacturers, GM is also working on moving to all-electric vehicles powered by fuel cells. That means integrating the mechanical, electrical, electronics and software design systems, which again needs high level modelling.
“We see the traditional combustion engine being replaced by electric propulsion with fuel cells,” says Burns. He led a five year project which ended earlier this year with an electric car that travelled over 300 miles on public roads. GM built two of these vehicles, called the Sequel, using high level modelling tools right from the start.
“The beauty is that when we developed the Sequel we built it all in math initially and were able to get them up and running in a relatively short period of time,” he says. “We have the fourth generation fuel cells with regenerative power, by-wire braking and Flexray standard systems. There’s never been a vehicle that puts together all these systems before.”
But it is not just the car itself. GM’s OnStar automatic crash notification technology, using GPS satellite navigation, notifies a hospital and ambulance of a crash.
Vehicle2Vehicle (V2V) technology adds a variant of WiFi to link cars on the road to exchange data.
“We have taken advantage of OnStar being standard on vehicles and the stability control keeps track of the wheel speeds and that allows us to work out the position to within 1m and predict where they will be in the next 20s,” says Burns.
“We will still have a few short range sensors but the key is the V2V. This sets up the possibility of vehicles that drive themselves and by 2015 the technology for autonomous driving will be here, and it is up to society to work out how it will be used.”
Cars are already being designed from the top down, with modelling systems for describing the whole system, including the software. “We can model the end to end delays from sensors to actuators with math based modelling tools such as those from The MathWorks,” says Burns at GM. “This allows us to capture the character of the car with software.”
Mentor Graphics sees the AutoSAR software standard as the way to link all the systems together at a high level.
“It provides an interface between these electronic control units and the system level electronics that allows for standard interfaces and builds a hierarchy from the applications software down to the hardware,” says Rhines. “The big problem is for every ECU there is application software, middleware networking software and typically these come from multiple sources.”
This is happening now, and Rhines sees full AutoSAR cars coming to market in 2010.
“The automotive industry is pushing for a true AutoSAR hierarchy much faster than anyone anticipated as there is cost pressure and complexity issues that the industry and supplies are pushing,” he says.
This has created opportunities for companies such as VaST Systems, not only with the chip companies but with the car makers to develop both hardware and software.
“The semiconductor companies are our partners – our customers are the tier one companies in the automotive supply chain where we are going to see the bigger deployments,” says VaST’s Labat. “Toyota is our number one customer and we have the top five suppliers supporting and developing platforms on VaST tools.”
“Today we are solving the software system development and verification problems,” says Jeffrey Roane, v-p marketing at VaST. “Hybrid vehicles will have over 100 ECUs so the software content is going through the roof and programming them all has always been challenging.”
As a result, VaST is also pushing AutoSAR. “We are engaging with the AutoSAR initiative,” says Labat. “It’s something we want to embrace and our customers want us to be there…, because this is going to be the key to adoption by the large OEMs.”
“We believe we are the de facto standard,” adds Roane. “Infineon has got to the stage of distributing VaST models to its customers to win business.”
But there are still gaps and challenges for the EDA vendor. The mixed signal tools for embedded flash and EMC modelling in automotive systems are still poor, so companies such as Infineon Technologies have had to design their own EM tools for devices such as the TriCore embedded processor.
“The big issue is the analogue/digital, and we never do any pure digital,” says Hartmut Hiller, senior director design methodology at Infineon. “My impression is that the EDA vendors cultivate the gap between these two communities.”
And the safety critical nature of the software is also vital for GM. “We are developing our own code translation rules, and a lot of this is pretty important because we are talking about safety critical systems,” says Burn.
This creates an opportunity for the vendors. “In analogue and mixed signal we can’t provide a simulator just for the processor so customers connect us to MathWorks for mechanicals, or Sabre for analogue, and co-simulate,” says Roane at VaST.
Automotive has become a key driver for design tools for high level modelling, or electronic system level design. Being able to model the whole of the car –software, electronics, mechanics and even its shape - allows the automotive designers to move faster and avoid the ‘perfect storm’ of rising costs, increased competition, eroding pricing power, and reduced time to market.
This extends even further to modelling the wider system with networking capabilities and links between vehicles that offers even more safety improvements to protect vehicle drivers.