BMW Reveals Body Wrap Allowing Colour Changes At Push Of A Button

With the ‘BMW iX Flow featuring E Ink’ presented at the 2022 Consumer Electronics Show (CES) in Las Vegas, the company says it is offering the prospect of a future technology that uses digitisation to adapt a vehicle’s exterior to different situations and individual wishes. This means the surface of the BMW iX Flow featuring E Ink can vary its colour shade at the driver’s prompting.

BMW said the fluid colour changes are made possible by a specially developed body wrap that is tailored precisely to the contours of the iX. When stimulated by electrical signals, the “electrophoretic” technology brings different colour pigments to the surface, causing the body skin to take on the desired colouration.

“The BMW iX Flow is an advanced research and design project and a great example of the forward thinking that BMW is known for,” said Adrian van Hooydonk, Head of BMW Group Design.

BMW said the E Ink technology opens completely new ways of changing the vehicle’s appearance in line with the driver’s aesthetic preferences, the environmental conditions or functional requirements, offering “unprecedented potential” for personalisation of exterior design.

“Digital experiences won’t just be limited to displays in the future. There will be more and more melding of the real and virtual. With the BMW iX Flow, we are bringing the car body to life,” said Frank Weber, member of the Board of Management of BMW AG, Development.

BMW said new technologies will provide a new level of decision-making freedom in the future. “This gives the driver the freedom to express different facets of their personality or even their enjoyment of change outwardly, and to redefine this each time they sit into their car,” said Stella Clarke, Head of Project for the BMW iX Flow featuring E Ink. “Similar to fashion or the status ads on social media channels, the vehicle then becomes an expression of different moods and circumstances in daily life.”

According to BMW, a variable exterior colour can contribute to wellness and efficiency of the vehicle. This is achieved by considering the different abilities of light and dark colours to reflect sunlight and associated absorption of thermal energy. For example, heating of the vehicle and passenger compartment, as a result of strong sunlight and high outside temperatures, can be reduced by changing the exterior to a light colour. In cooler weather, a dark outer skin will help the vehicle absorb noticeably more warmth from the sun.

BMW said this reduces the amount of energy the vehicle’s electrical system needs and therefore fuel or electricity consumption. With reduced energy usage, a vehicle would gain a greater travelling range.

“E Ink technology itself is extremely energy efficient,” BMW said. “Unlike displays or projectors, the electrophoretic technology needs absolutely no energy to keep the chosen colour state constant. Current only flows during the short colour changing phase.”

BMW said electrophoretic colouring is based on a technology developed by E Ink that is well known from the displays used in electronic reading devices. The surface coating of the BMW iX Flow featuring E Ink contains many millions of microcapsules, 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 body the desired shade.

Achieving this effect on a vehicle body involves the application of many precisely fitted ‘ePaper’ segments (display devices that mimic the appearance of ordinary ink on paper by reflecting light, rather than conventional flat panel displays that emit light). Generative design processes are implemented to ensure the segments reflect the characteristic contours of the vehicle and the resulting variations in light and shadow. The generative design algorithms enable the necessary formability and flexibility required to tailor the ePaper exactly to the design lines of the vehicle.

BMW said laser cutting technologies guarantee high precision in generating each segment. 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.