How Usable is YOUR World?

Have you ever turned the wrong knobs for your stove burners? I have read about natural mapping and how stove are badly design. Don Norman, in his book The Design of Everyday Things, and Kim Vicente, in his book The Human Factors, mentioned this issue and proposed few designs.

I decided to talk about it because in the last month, I have seen my flatmates turning the wrong knobs a couple of times, even this morning. We have a conventional stove with 4 burners and a row of knobs as many stoves have. Here is a picture of ours.

Stove burners with a bad natural mapping

The common error is, for example, to turn the Front left burner instead of the Front rear. The confusion is usually between rear and front. The reason behind that is the bad mapping between the knobs row and the burners. There is a bad spatial arrangement of the knobs versus burners. Here is a closer look at the knobs.

Aligned knobs

Natural mapping consist in positioning controls in relation to their outcome in the world. As for example, the stove’s knobs should be spatially arranged in the same pattern as the burners. A proper design could be :

Proper mapping

While designing, you also have to take into considerations other constraint such as the width of the stove. Sometimes, that kind of oven would not fit in your kitchen because of its width. Another solution in that case could be to align knobs while changing their size to represent different sizes of burners as in the following draft.

Different knob size

As Don Norman points out in his book:

“If a design depends upon labels, it may be faulty. Labels are important and often necessary, but the appropriate use of natural mappings can minimize the need for them. Wherever labels seem necessary, consider another design.”

A good example, but not related to natural mapping, of “Wherever labels seem necessary, consider another design” is the Exxon bad interface gas pump. They added a red button stating: Push to Start close to a yellow sign that have been (erroneously) pushed instead.

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bad design by Olivier Lorrain