Archive for January, 2008

Integrating the GUI and Off-screen Controls: Camera Example

Sunday, January 6th, 2008


Quite often the GUI on an embedded device is driven by the software team while the off screen controls are designed by the mechanical or electronic designers. Sometimes this leads to a system were these two parts of the same device are not well integrated. I have seen cases were icons or names used on the GUI are not consistent with those used on the housing.

On the other hand some devices do a beautiful job of marrying the two types of input. On my Sony camera, there is a dial which allows the user to choose the mode. The dial contains small icons. When you turn the dial you get to see the full name and a description of the new mode. This vanishes after a few seconds, so the extra information does not clutter the image of the picture to be taken.

By also showing a rounded outline around the icons being selected, the on-screen image looks like an extension of the physical dial. In other words, rotating the off-screen dial also rotates a disk that is displayed on the GUI. While this is tricky to describe the brief video below makes the idea clear.

While many other cameras only repeat the icon on the GUI, Sony make this feature far better in two ways. One is that the extra text means that the user can learn the meaning of the icons without resorting to the user manual. The second aspect is the smooth integration of the on-screen and off-screen controls makes this device feel like a single user interface, rather than two distinct interfaces to two different parts of the device.

Tradeoff: Easy on the Eye or Easy to Use

Tuesday, January 1st, 2008

Traveling with work I spend plenty of time in hotels. I noticed that the more expensive the hotel, the more expensive the bathroom fittings. However the more elegant and eye-pleasing the taps and faucets, the harder it is to see which is the hot tap and which is the cold. Some designers focus on form and not function. That sometimes hides the information the user needs. Large red and blue plastic moldings take away from the ascetics of the design, but they do tell the person which tap is hot and which is cold.
The same principle applies to many embedded systems – there is a trade-off between pretty and easy-to-understand. That is why kids toys have big buttons in primary colors. Easy to see and manipulate but not so pretty to look at. Think about that the next time the mechanical designer on the team is trying to make the buttons small an discrete to avoid interfering with the smooth outline of your next product.