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The first part of our interface is the floor selection kiosk in the lobby. It is the first thing the user encounters when entering the elevator lobby, and its button layout is identical to the buttons inside a traditional elevator. Pressing one of these buttons will summon one of the available elevators to the current floor, and assign it to the selected target floor (among other existing target floors, potentially.) Once a button is pressed, it glows with a color that corresponds to the summoned elevator. It also temporarily displays a letter that corresponds to the elevator, to remove ambiguity for the colorblind and in cases where there are many elevators. A screen at the top of the panel displays a map of the elevator lobby. When one of the buttons is pressed, a colored route is overlayed on the screen, directing the user toward the elevator that has been summoned for them.
The form factor of this panel was heavily debated in our early planning. Having it be so vertical may limit the number of users that can concurrently access the panel, if the lobby is crowded. We developed a horizontal version of this, but it wasn’t recognizable enough as an elevator floor-selection panel. Given that our primary obstacle in this project is training people to treat this panel as a floor-selection panel, we opted for a familiar vertical button layout.
We also had to decide whether to use colors or letters to identify elevators. Using colors would allow users to identify their elevator from a distance. Colors are also easier for users to remember in the short term than letters, which is why they are used to distinguish floors in parking structures. Letters, on the other hand, remove all ambiguity in the case of a building with a very large number of elevators. They are also more accessible to the color-blind. We opted to use both letters and colors to represent floors. While this slightly confused one of our testers, the benefits of using both letters and colors are worth the slight decrease in simplicity.
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