Autodesk saves the Chevy Volt from 'aerodynamics of a boulder'

Autodesk saves the Chevy Volt from 'aerodynamics of a boulder'

Aside from the futuristic display that told me I was running only on electric power -- and a reminder that I had 19 miles before the car’s Voltec drivetrain would switch over to an internal combustion engine -- there wasn’t much about my maiden voyage in a Chevy Volt that screamed “eco.”

In fact, the design is so unlike the quirky Toyota Prius and the boxy Nissan Leaf, one could easily walk past the Volt parked on a street without realizing it's a plug-in-electric extended-range car that can get an equivalent fuel economy of 60 miles per gallon (when combining the mileage derived from the Volt’s electric engine, fully charged, and its internal combustion engine.)

That, many would argue, is a good thing. In order to enter the mainstream, fuel-efficient cars might benefit by looking, well, mainstream. But after my spin in the Volt, at a test-drive event at the Autodesk campus in San Rafael, Calif., on Friday, James Bell, General Motors’ head of consumer affairs, told me that the original Volt concept car actually had a much more aggressive “muscle-bound green car” look that consumers loved but which, unfortunately, “had the aerodynamics of a boulder.”

Poor airflow around an electric hybrid car would hurt its efficiency rating, which would hamper its prospects for gaining traction with U.S. drivers (something that, despite poor initial sales and a production hiatus, appears to now be growing for the Volt). So GM turned to its designers and engineers to improve the Volt’s aerodynamics, and these designers and engineers turned to Autodesk software and simulation tools, says Carl White, director of manufacturing engineering products for Autodesk’s Design, Lifecycle and Simulation Product Group.

GM’s goal was to boost the car’s efficiency in the design phase so less tweaking would be required, further down the road.“Putting a little bit more effort in up front pays a lot of dividends on the back end, and simulation is something we’re really trying to make available to more and more designers,” White told me. “A great example of that is air flow over the [Volt]."

Air flow is typically something that only gets heavily studied after a lot of design decisions are already made from an aesthetics standpoint, he explained. But Autodesk has software it calls Project Falcon that's able to simulate wind tunnel testing for different designs in real time. "It’s not 100 percent accurate, but it’s enough to allow somebody to flow air over a car and understand what raising an angle, say, 1 percent, might do to airflow at the back of the car," White said. "You still need to do [real] simulation and put it in a wind tunnel, but we want to bring that aspect closer to the person who is actually using the software.”

Using software to better understand the way air flows around a car design is one of the many ways GM used Autodesk products in the early concept and design stages of the Volt, White said. “Both the exterior and interior are styled using Autodesk Alias products. That starts from the initial concept sketches that go through design review within GM and moves into the design of the 3D model for the actual car, itself.”

Using Autodesk software to design vehicles also helps GM cut significant waste, both in the early design and testing phases and in manufacturing, Bell said. The software cuts “waste of materials, waste of time, waste of travel effort, everything,” he claims. Whereas designers previously relied on clay models that were put through multiple iterations -- each of which required signoff from various departments within the organization, requiring significant time and travel -- simulation software means that small changes can be made quickly, repeatedly and, White added, “long before any metal is cut for a mold, long before any plastic is flowed into that mold.”

Because the Volt’s extended-range electric-propulsion system -- which it calls the Voltec drivetrain -- is a fundamentally new type of automobile, GM’s designers and manufacturing engineers were especially interested in using Autodesk tools to evaluate things such as material performance and how the weight of various components would impact the car’s performance and efficiency.

Aside from Alias and Project Falcon, GM designers also used Autodesk software tools called Maya and Showcase to create photorealistic visual models, as well as the company's Simulation Moldflow to analyze the plastic parts and to optimize the Volt battery pack for performance and also manufacturability. (The battery pack is what enables the car to be recharged with electricity.)

GM also used Autodesk AutoCAD, AutoCAD Architecture and Autodesk Navisworks software for layout of the Volt factory at GM’s Detroit-Hamtramck assembly plant, which is incorporating a major photovoltaic power system.

Now that GM is using its Voltec technology in new models, including the highly anticipated Cadillac ELR and in “other vehicles I can’t talk about right now,” Bell said, the design work and Autodesk tools that went into the Volt are serving as a foundation for designers who will, as he put it, “just keep moving the game forward.”

Read more about the Chevy Volt on GreenBiz:

Top photo courtesy of General Motors; video and second photo by GreenBiz contributor Mary Catherine O'Connor.