The Tesla Model S is a fully electric sedan introduced in 2009. It's most remarkable feature in addition to the completely electric drive train powered by a lithium ion battery is the digital center console consisting of a 17„ touchscreen display. The instrument panel is powered by a 12.3“ display which results in a completely digital interior without any analogue gauges.

While a touchscreen of this size is remarkable for a production car, the interface is already starting to look outdated compared to current smartphones and computer interfaces which adopted a more minimal and flat style. The Tesla's interface still tries to resemble real-world switches and buttons - it's debatable if this style is still appropriate today given the possibility of over-the-air updates by the manufacturer.

We designed a head-up display for the Tesla Model S which seamlessly blends into the default interior and displays only the most relevant information to the driver. While the huge dashboard and center console displays inside the car are great for displaying rich information and media they are just as distracting for the driver. This lead us to further simplify the head-up display to only consist of the very necessary information the driver needs while focusing his eyes on the road. Mirroring too much information from the dashboard display would be distracting and counterproductive. Additionally the head-up display is designed without any additional controls - it adapts to different situations automatically without additional driver interaction.

The head-up display's layout is divided into two cirlces. The first circle is centered above the steering wheel and displays the driving speed and the remaining range. Especially the range is important due to the still low density of chargers around the world. Tesla drivers still need to plan their journeys in advance to avoid running out of power.

Additionally the speed limit is displayed above the driving speed. Once the driver decides to exceed the speed limit the circle around the speed limit will blend into a red color. This is only a small reminder to the driver to avoid any patronizing.

Three bars around the circle mirror the three pointers of the dashboard indicating the speed (blue), power gain (green) and power drain (red). We included these bars in the head-up display since they are an important indicator to efficient driving and are an exclusive feature of an electric car. The position of the blue speed indicator gives an idea of the current driving speed without actually reading the numbers.

A second circle appears to the right either shortly for alerts or permanently if navigation is active. A bar appears around the circle indicating the distance to the next turn. It slowly depletes until the turn is overdue and disappears afterwards. Additionally, the distance is shown under the circle while two lines above the circle are reserved for displaying street names.

The font used for the Tesla Model S’ interfaces is Gotham, so it was only logical to use the same font for the head-up display. We use Gotham Medium for text and street names and Gotham Bold in a monospaced variation for displaying numbers. While Gotham may not be perfect for head-up displays it fits well into Tesla’s branding and a different font would make the display seem out of place.

We wanted to make sure the display works under all circumstances so we recorded some journeys in extreme light conditions to test line widths (hair-lines don’t work). A wooden prototype made out of a reflective sheet of glass and an iPad helped us to find the right font size and gives a better impression of how the head-up display works in a real car.

Startup phase with the Tesla logo and parking position

Gear set to (D) drive

City traffic with speed limit

City traffic exceeding speed limit

Highway traffic in extreme light conditions exceeding speed limit

Highway traffic with active navigation

Highway traffic with active navigation, turn imminent

Highway traffic with active navigation, turn overdue

Highway traffic with active navigation, turn complete

City traffic, road work alert

City traffic, low battery alert

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©Constantin Eichstaedt

First prototypes helped adjusting the design parameters (strokeweight, colors, typesize) to the different sight conditions.

A head-up display allows the driver to focus on relevant information without diverting his eyes from the street. We decided to only focus on the most important information relevant for the driver's safety and navigation. Everything else is already covered by the large screens of the center console and the dashboard so mirroring more information would only have led to further distraction. Our goal was to create a head-up display that would show all required information to safely drive the car without looking at the dashboard or center console.