Design Diary

Evaluation: Despite its modern appearance, the sound system and control panel have a number of design mistakes. First, the interface has a low signal-to-noise ratio. The number of irrelevant or rarely-used options displayed, particularly on the screen, outnumbers the number of relevant or frequently-used controls. There are so many features that some buttons have as many as four functions. Due in part to the overwhelming number of features, performance load is high, meaning the effort needed to complete tasks is greater, and users may be more prone to error. Additionally, cognitive and kinematic load are both particularly high when selecting music on the screen from a connected device.  The user must scroll the tune button to select a song, but if a song is scrolled over and not selected via button press, the cursor goes back to its previous location after a few seconds without movement. This means that if a user wants to go from a song beginning with “A” to a song beginning with “Z,” they could have to start over multiple times if they do not move quickly enough and do not select a song. The high performance load makes the system more difficult to operate, particularly while driving. The interface also has several false affordances. First, the audio and A/C knobs can be turned in either direction. However, the audio knobs also serve as buttons, while the AC knobs, though similar in appearance, cannot be pressed. Second, the head of the sitting figure, which shows where air is blowing, is a false affordance. The body is a button that can be pressed, and the head looks exactly the same but cannot be pressed.

I would also argue that this technology represents a lost opportunity to make use of the MAYA principle. The interface is clearly modern, but aside from the naturally mapped airflow controls, no aspect of the design stands out as novel or different from those in other vehicles. The designers would likely be able to get away with making the interface more aesthetic and avant-garde without deterring consumers or eliminating familiarity.

However, the interface is also well designed in several ways. The sitting figure is naturally mapped to represent where air is blowing. For example, if a lit-up arrow is pointing to the figure’s head, then air is blowing toward the face. This makes it much easier for the user to recognize where air is blowing and how to change its direction. The icons used for controls are largely externally consistent; they are similar to industry standards. For example, the windshield defrost buttons, the CD player’s eject button, the fan button, and the air circulation button all use icons similar to those found in other cars. The AC and audio player knobs use constraints- they are limited in range of motion, which in turn limits the possible ways the user can turn them to adjust settings and minimizes user error. Finally, the display is backlit with blue light, which promotes alertness. This is especially appropriate for design in a car, where the driver must remain alert at all times.

I would also argue that this technology represents a lost opportunity to make use of the MAYA principle. The interface is clearly modern, but aside from the naturally mapped airflow controls, no aspect of the design stands out as novel or different from those in other vehicles. The designers would likely be able to get away with making the interface more aesthetic and avant-garde without deterring consumers or eliminating familiarity.