General Motors Is Transforming How It Architects Its Vehicles To Meet the Future

MotorTrend, in partnership withBlackBerry, set out to highlight the heroes of the Software-Defined Vehicle revolution. The pioneers who led the way and the innovators behind what's to come. These are the people plotting the future of transportation as we know it, using software as the catalyst. In order to achieve this, MotorTrend created a 172-page book, a 22-minute documentary, and hosted the first-annual Software-Defined Vehicle Innovator Awards in Las Vegas during CES 2023.Click Here to download the 172-page eBook and watch the Coding The Car documentary. A version of one of the stories  from the Coding the Car publication is presented below.

Scott Miller's nearly two-decade career at General Motors has coincided with some of the most substantive changes in the history of the automobile in general and GM in particular. Miller joined the automaker around the same time it was taking back the EV1 from customers and sending them to the crusher. He went straight to work on GM's hybrid programs, then later moved into CO2 strategy and automated vehicles. The common thread across all those positions is software, making Miller a logical choice to be GM's vice president of its software-defined vehicle and operating system efforts.

"I created speed-based throttle control," he said. "I had to create all the tools to calibrate it in the closed loop to go straight from math data to calibration files, so when you make a speed-based throttle progression table that has 1,300 calibration points, you've got to have tools to do it."

The origins of embedded software in vehicles reaches as far back as the early 1970s, when the first microprocessors became available and were quickly adopted as an enabling technology to meet new emissions and fuel-economy requirements. Through the mid-2000s, as Miller was getting his feet wet at GM, the number of functions powered by software started to grow, although they remained mostly isolated from each other.

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New Powertrains, New Software

But that began to change as hybrid and other related technologies emerged. "I started doing hybrids, and when you have multiple powertrains or propulsion sources, integrating them becomes pretty paramount. And then battery technology," Miller said. "Going from software-controlled to software-enabled. That's been getting better and better. The reason you can have a 1,000-horsepower vehicle right now is because the software can keep it from disintegrating itself. So software control has been taking advantage of the computing power, the precision, the latency time, the memory, the cost curve."

Speaking of 1,000-horsepower vehicles, the most powerful street-legal production model ever produced by GM, the Hummer EV, is a machine that would have been impossible to bring to market not so many years ago. One of the biggest reasons why has to do with the advancements Miller and his team have been making.

While the Hummer has been a major triumph for GM from a software perspective, like many of the world's top automakers, GM has areas where it must improve, among them connecting its vehicles to the world. "This desire to have more software-defined features, it's been just exploding," Miller said. "And then with connectivity, how do you integrate that with the Internet of Things or with the cloud? To integrate that real-time operating system gets harder and harder."

Even when the over-the-air lines of communication are available, making on-the-fly changes presents its own set of challenges. "Every time you change something, whether it's one of the computers on the network or a signal on the network, it takes a lot of reintegration of the same stuff to get the robustness," Miller said. "So we spent a lot of time just integrating and getting the robustness for minor changes, and it becomes very brittle. Once you get it to work, it's like if you touch it, sometimes you break three things just to add one new thing."

Making Fundamental Architecture Changes

Given the issues Miller outlined, it was clear that GM needed to overhaul how its vehicles were developed from a software perspective. His primary work over the past several years has been doing just that. Miller's been overseeing a fundamental re-architecting of GM's vehicles known as Ultifi, the automaker's new end-to-end vehicle software platform. There was a time when software was tightly coupled to the underlying hardware until Tesla demonstrated a new way forward with its Model S. Ultifi represents some of the lessons learned.

"The level of effort, the level of quality expectation, the level of features are just driving this to a point where it's becoming not sustainable with the rate of growth of software features people want," Miller said. "So that's why we're creating Ultifi. What we're doing is abstracting a new platform, a new operating system on top of our mechatronics."

Platforms like Ultifi act in a similar fashion to the way Android or iOS do on a smartphone. From model to model or year to year, manufacturers are constantly updating the chips they use, but app developers can largely ignore the hardware updates and just use the software interfaces provided by Google or Apple.

"So I need to extract the signals in the actuator controls into this higher-level [Ultifi] platform. And then we're going to build the software into services and apps that make sensors or sensor data or actuator controls available generically," Miller said. "It's like an API; once you build it, you can use it across everything. I don't have to re-integrate that every year. It's a foundation that's built. Now I can build new features by making apps that call the services, and I can combine camera services with door-lock services and create a new feature that locks the rear door when it recognizes a kid in the back seat."

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Software is Big Business

Miller's boss, GM CEO Mary Barra, has publicly stated a goal to double company revenues by 2030. This aggressive target is based in large part on how well GM will be able to use software to create features that customers will pay for a la carte, even years after they buy the vehicle. Ultifi is being designed in part to help GM make that happen.

"We need the right tool for the right job. You need a real-time operating system for the hardcore ASIL [automotive safety integrity level] actuator control, the very precise, low-latency response stuff," Miller said. "But then when we abstract these APIs, we can reach into the vehicle like a remote control, build that on this Linux platform, and then make services that then we can create new features very quickly via apps or integrated with the cloud very easily."

According to Miller, Ultifi will also help facilitate a constant stream of data that will allow GM to understand how its customers are interacting with their vehicles. "Another big part of this is this continuous integration loop where we're always seeing what are the people using, what are they loving? What are they not liking?" Miller said. "With automated driving stuff we could tell when the system didn't work perfectly, when they had to take over. We don't have to wait for them to call and complain, right? So we can make this a smart system that helps us make it better, as well."

The Stars Behind Future Cars

From Charles Kettering to Zora Arkus-Duntov to Ferdinand Piëch, the mechanical engineers who created the powertrains and platforms along with the designers who sculpted the sheetmetal were long considered the rock stars of the auto industry. They gave each brand its own unique identity. But as the transition to electric propulsion has accelerated, a lot of that variation is disappearing. Software-defined features and the developers like Miller who create them are beginning to come to the forefront. They will create new brand identities, develop new products to dazzle customers.

"Last year was the first year that 50 percent of our new hires were software. So our recruiting is now more software than hardware," Miller said. "Not that we're not recruiting both; we're still recruiting a lot. But this is the first time that software became the higher percentage."

It's a transformation that Miller has had a front-row seat to during the course of his career. While he's worked alongside legions of hardware-based engineers and others at GM charged with creating its next-generation electric motors, batteries, and electrical architectures, increasingly it's Miller and his division serving as the orchestrator. It's a role that's become as crucial as any, if not more so, to ensuring the future success of the century-old company.

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FAST FACTS: SCOTT MILLER

Resume Key Points

• Executive director vehicle motion and embedded controls, GM
• Executive director and executive chief engineer for AV, ADAS, and electric vehicle integration, GM
• Director of AV integration, GM
• Director CO2 strategy, energy, mass and aerodynamics, GM
• Vehicle performance manager, Voltec and RWD hybrids, GM

Education

• Bachelor's degree in aeronautical engineering, Embry-Riddle Aeronautical University
• Master's degree in mechanical engineering, The Catholic University of America

Present Position

• Vice President, Software Defined Vehicle and Operating System at General Motors

Hometown

• Altoona, Pennsylvania

Currently Residing

• Lake Orion, Michigan