The Ngāti Porou woman who invented BMW’s colour-changing car

Engineer Stella Clarke demonstrates BMW colour-changing technology at the Consumer Electronics Show in Las Vegas in 2023. The car body is covered with e-ink cells, which can be controlled via a smartphone app. Photo / Getty Images
Choosing the colour of a car at the time of purchase might soon be a thing of the past, thanks to work by a BMW engineering team in Munich led by Dr Stella Clarke (Ngāti Porou) – which has developed e-ink cells that cover a vehicle and can change colour in seconds with a tap on a smartphone app.
Demos of the technology wowed the crowds at the giant Consumer Electronics Show in Las Vegas in 2023.
Clarke, who is of East Coast Māori and Chinese/Indonesian descent and (whisper it) born in Australia, has been working on cutting-edge tech for the German car maker in Bavaria since 2007.
The Herald caught up with her during a recent visit to Auckland.
That would have made a good story, and I do love taking things apart to see how they work, but that’s not how this all started. My interest in haptics was triggered by an awesome PhD topic at the Technical University of Munich which involved remote control of robots using haptic input devices. My interest in e-ink started when I simply read an article about how [it] works.
It’s absolutely fascinating, and the most incredible thing about it is that it’s bistable, which means it needs no power to hold a colour. Back then, and still now, I find this incredible. Imagine a future where, in the morning, you can choose the colour of your car.
To change the colour, you only need a bit of energy in the morning – approximately 20 watts for the duration of 10 seconds – and the whole day it remains that colour without consuming any energy. Pretty amazing. So it started with a theoretical interest in how e-ink works.
Actually, I would have liked to have taken apart a Kindle. But the truth is, taking apart a Kindle to isolate the e-ink layer wouldn’t really work.
These layers are laminated together, and taking apart this laminated stack would probably destroy the colour-changing layer.
We still have challenges to overcome, particularly in the direction of robustness, so I am hesitant to give an exact time frame. The testing of the material alone takes multiple years to complete. Perhaps five years, plus or minus.
Not at all! It’s bistable. Battery life and low energy consumption are exactly where this technology stands out. Anyone who owns an e-reader knows how long it lasts on a single charge. Our cars have the same advantage. When we travel around for shows, we usually don’t need to plug in a charging cable to our cars, as the colour change consumes very little energy.
Exteriors will be bought to life; we’ve already started seeing this. Customisation will increase in significance. Transportation will not only be about the driving experience, but also about the living experience.
Interiors will become more pliable. Transitioning from living to driving will become increasingly seamless. I’m looking forward to it.
I do! Actually, getting to work by bike doesn’t cost me much more time than driving or taking public transport, and I get in a somewhat decent cardio workout.
I get a kick out of time efficiency, and I’m often too lazy to do sports in the evening.
Additionally, my commute to work is now shorter than previously, and the winters in Munich are getting milder, so it’s not that much of a feat nowadays.
But I have vivid memories of long bike commutes to work in -15°C weather. That’s painfully cold.
I’d need to take breaks in multiple bakeries along the way to work, so that I could defrost a bit.
I also recall a few days where the snow was so deep that I couldn’t pedal anymore and needed to walk with my bike. For icy surfaces the solution is spikes on your tyres.
For deep snow, sometimes the only solution is to get off your bike and push … and be late to work.
Ngāti Porou.
Ko Hikurangi taku maunga. (Hikurangi is my mountain)
Ko Waiapu taku awa. (Waiapu is my river)
Ko Ngatiporou taku iwi (Ngāti Porou is my tribe)
Very proud of my Maori, and my multicultural, heritage. I grew up in Australia, but we’d spend most summers in New Zealand with whānau.
My dad was one of 13 children, so I have heaps of cousins. Such fond memories.
If any of the following is relevant to you ….
… then you may get a lot of joy out of studying engineering and becoming an engineer!
It’s really fulfilling.
Over the past three years, we’ve created three colour-changing cars which we’ve shown audiences around the world.
My favourite pictures of our cars are not the cars themselves, but the images of delight on peoples’ faces when they see our incredible creations.
What more could an engineer want!
Chris Keall is an Auckland-based member of the Herald’s business team. He joined the Herald in 2018 and is the technology editor and a senior business writer.