Creating Cars That Become Your Ultimate Driving Partner

At the heart of Mazda's car design is Jinba-ittai, the philosophy of horse and rider as one. Just as a skilled rider and horse move in perfect harmony, a Mazda responds naturally to the driver's intent, moving exactly as they wish. Mazda has spent years making that feeling accessible to every driver.

At the foundation of that pursuit are two things: human research, which engages directly with how people feel and sense the world, and the expert drivers who have spent years perfecting the feel of every car.

Now, a new challenge is underway: bringing Jinba-ittai into the design process earlier than ever before.

In this article, we explore the intersection between research, development, and evaluation, and how a car comes closer to becoming the ultimate driving partner.

At Mazda, car engineering begins with understanding people. Daichi Sato embodies that thinking at the forefront of research.

Human research spans several fields. Ergonomics improves usability and safety based on people's physical characteristics. Kansei engineering applies science to feelings like comfort and pleasure. Kansei neuroscience uses brain response to understand how people experience safety and well-being.

My own work focuses on modelling driver and passenger perception and sensation, and on how people move and control their posture while in a vehicle. Using an electric wheelchair, I collect data on how people move and what they feel, then build simulation models^* that connect people and cars.

Human research is something most people would associate with a university. Why does a car manufacturer pursue it?

I've been conducting analysis and research related to people since my student days, but back then I struggled to turn those findings into everyday products. At Mazda, research flows directly into engineering. I can see how my work feeds into actual cars, and that connection gives me a real sense of purpose.

For example, the research showing that darker interior colors speed up the brain's response to external stimuli has already been applied to production cars. Seeing research findings become real value in a product keeps me motivated to push further.

What do you find most challenging about human research?

Say we're running a test drive in rain with poor visibility. Even if the driver uses their skill and experience to keep the accelerator and steering perfectly consistent, we can't control the volume of rain or how it falls. And that difference can throw off the experimental results.

Mazda has been conducting human research for many years, and every test required expert drivers at the wheel and carefully controlled conditions. That took enormous time and cost. But because this research directly connects Jinba-ittai and how secure a Mazda feels to drive, it was always worth the effort.

We understand there are new developments in how Mazda refines the Jinba-ittai feel. Suzuki, could you tell us more about this and your work?

What do you mean by "cultivating" the simulator?

Simulators aren't like arcade racing games where you just put in a coin and start driving. Before the driver can start, you need to prepare road surface data, visual data, and vehicle motion models, load them into the simulator, and then confirm everything is working correctly. Only after doing all of that can the driver get in and start driving.

What matters most is time consistency. To control a simulator properly, one second in the real world must equal one second in the simulator. No matter how precise and detailed our models are, if the simulator's processing can't keep up, time discrepancies accumulate during experiments. The key is building models that maintain the necessary accuracy while simplifying where appropriate. It takes specialist knowledge, but this is precisely where the skill of an engineer to "cultivate" the simulator really shows.

From there, expert drivers get in and work through every nuance, carefully fine-tuning until the simulator feels as close to a real vehicle as possible. It's a genuine two-person effort between driver and engineer. Some drivers even wear blindfolds until they're seated in the simulator seat, blocking out external information to immerse themselves fully in the feeling of being in a real car.

How are driving simulators being used in development?

By bringing simulators in earlier, we can evaluate performance in virtual space before anything physical is built and prevent major setbacks. Driving simulators are an essential part of Model-Based Development (MBD) at Mazda.

But development efficiency isn't our only goal. What we're really after is creating time, the time needed to carefully build the drive feel we're aiming for.

Still, real vehicle testing seems hard to beat.

Take vibration evaluation. In a real car, when you feel vibrations through the steering wheel, it's difficult to tell whether they're coming from road surface irregularities or the vehicle's own structure. But in a simulator, we can create a perfectly flat, smooth-as-ice surface, and isolate exactly what's causing the vibration. That kind of precision makes uncovering the mechanisms behind ride comfort and drive feel much more straightforward.

That makes it easier to identify what's causing the phenomena we observe. Once we understand the causes, we can make real progress in modelling human sensation and deepen our understanding of how drivers and passengers feel and respond inside a car.

What do we gain from understanding these mechanisms?

It's like writing down a secret recipe so it can be passed on to the next generation. The result is that we can deliver Mazda cars that embody Jinba-ittai at higher quality and with greater speed, generation after generation.

Finally, what's your vision of the ideal car and your outlook for the future?

I want to understand each customer's sensations, emotions, and physical condition, so we can create cars that become true partners that people can connect with. That's where driving simulators come in - they're the bridge between human research and car engineering.

Ideas come up along the way about interesting things that could be built into a car. But I always ask: will this genuinely enrich customers' lives and bring them happiness? And will customers truly feel its value? That customer-centric perspective is something I never lose sight of.

When I said in my Mazda job interview that I wanted to create cars that become true partners to people, I hadn't really thought about how I was going to do that. But now I can see that is exactly what human research is working toward.

And that's not the only change. My family has grown, and it's made a big difference to how I think. That's why I want to create cars that can foster understanding and connection between people and cars. Cars that families want to take out, making lasting memories together. Cars that feel like your ultimate partner. That's what I'm working toward.