The changing colour can make the BMW car more efficient by taking into account light and dark colours in relation to reflecting sunlight and the absorption of thermal energy.
05 Jan 2022 | 4426 Views | By Autocar Pro News Desk
BMW has revealed a host of futuristic technologies at this year’s CES but what decidedly turned heads is the car that changes colour instantly. The BMW iX Flow, featuring E Ink, is the first car in the world whose exterior colour can change at the touch of a button.
The changing ...
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BMW has revealed a host of futuristic technologies at this year’s CES but what decidedly turned heads is the car that changes colour instantly. The BMW iX Flow, featuring E Ink, is the first car in the world whose exterior colour can change at the touch of a button.
The changing colour can make the car more efficient by taking into account light and dark colours in relation to reflecting sunlight and the absorption of thermal energy. “By changing the colour of the car, we’re bringing personalisation to unforeseen levels,” said head of the project Stella Clarke. “We also see a lot of benefits from a usability and sustainability viewpoint.”
BMW explained, “A white surface reflects a lot more sunlight than a black one. Heating the vehicle and passenger compartment as a result of strong sunlight and high temperatures can be reduced by changing the exterior to a light colour. In cooler weather, a dark outer skin will help the vehicle absorb more warmth from the sun. In both cases, selective colour changes can help to cut the amount of cooling and heating required from the vehicle's air conditioning. This reduces the amount of energy the vehicle’s electrical system needs and, with it, the vehicle's fuel or electricity consumption.”
This principle could also increase the range of an electric car. The technology itself uses no energy to keep the chosen colour. Current flows only during the short colour-changing phase.
There is no confirmed production date, but Clarke said, “This is a first try. It’s never been done before. We’re pioneering it and are hopeful it will go into production. At the moment, we can’t tell you when it will come.”
How does it work?
The colour changes are made possible by a specially developed body wrap tailored precisely to the contours of the iX Flow. When stimulated by electrical signals, the electrophoretic technology – similar to that used in Kindle e-readers – brings different colour pigments to the surface, causing the body skin to take on the desired colour.
There are millions of paint capsules in the custom wrap, with a diameter equivalent to the thickness of a human hair. Each of these microcapsules contains negatively charged white pigments and positively charged black pigments. Depending on the chosen setting, stimulation by means of an electrical field causes either the white or the black pigments to collect at the surface of the microcapsule, giving the car the desired shade. Achieving this involves using many precisely fitted electronic paper segments, which are designed to reflect the contours of the vehicle and variations in light and shadow.
After the segments are applied and the power supply for stimulating the electrical field is connected, the entire body is warmed and sealed to guarantee optimum and uniform colour reproduction during every colour change, said BMW.
Clarke said early indications show that repairing the technology won’t be a huge issue. “It is certainly repairable and not unrealistic from that aspect,” she said.
Other BMW projects at CES included a 32-inch cinema screen extending from the headliner for rear passengers and a variety of sounds created especially for its electric models.
The German car maker said the innovations “combine creativity and digitisation to produce great moments for the driver and passengers.” The firm also revealed the BMW iX M60, a 620hp range-topping EV from its M performance division, at the event.