Onboard Computer
Onboard computers allow users to accomplish tasks such as starting music playback, using the GPS navigation, adjusting the air conditioning, etc.
They allow to reduce the number of buttons in the car but are dangerous to use while driving. Indeed, most actions are indirect and require a few steps. Moreover, because of the touchscreen interface, users can't perform an action without looking at the onboard computer screen. When they want to do something on the computer, drivers have to share cognitive resources between the driving and using the embedded device. It is called driver distraction: as an HMI designer, my primary task is to avoid it as much as possible to preserve user safety.
I was the HMI designer in charge of one of these modules.
*The images above are examples of similar systems and are not representative of the onboard computers I worked on.
What follows is an example of my work on the HUD module.
request
I was asked to make a mock-up (using Axure) of the system based on a specification document. The objective was to check and improve the flow.
My task was to support the design and development and to make sure the system was usable.
constraints
I had to respect various internal and other design criteria to limit driver distraction. For example, the onboard computer navigation buttons have to be on the driver's side of the screen to be more accessible; the size of touch areas has to be big enough, and there needs to be sufficient space between different elements to avoid inadvertent activation.
All these rules constrained the user interface design a lot. Moreover, the system had to be designed for a small screen.
Besides, the vehicles that will have this system installed won't all have the same options. Because of that, the system should be easily adaptable.
methods & results
Making the mock-up brought a lot of issues to light. In the course of the design process, I conducted iterative user tests to try different solutions.
I worked on both the virtual (e.g. touch screen buttons) and physical (e.g. scroll wheels) interface elements of the module.
I performed several heuristic evaluations and made recommendations to guide the design process toward the optimal solutions.
Once the specification document was completed, I started to work with the graphic designer. After multiple iterations, the graphical user interface was chosen.
The guideline and specification documents were sent to the manufacturer. Together with the HMI architect and the graphic designer, I ensured that the requirements were followed.