| Today's electronic equipment has a wide range of | | | | the final device. They can quickly see how easy |
| interface options. Custom keypads allow engineers | | | | controls are to reach, how convenient they are to |
| nearly unlimited possibilities in control design, | | | | use, if the feel of the keys is right and so on. |
| however those possibilities can lead to problems if | | | | Prototypes should be tested internally at first to |
| the interface is not carefully examined. | | | | fix the most glaring flaws, but should always be |
| Simple Example: 10-Digit Keypad | | | | tested at some point by potential customers. |
| Even the basic 10-digit keypad is actually an | | | | Your staff already knows how the equipment |
| example of custom keypads. Why? Look at your | | | | should work. By putting it in the hands of a new |
| phone then look at your computer. Both of them | | | | user, you find just how intuitive your custom |
| use 10-digit keypads and yet they are upside | | | | keypads are. |
| down in relation to each other. People who use | | | | A Nearly Tragic Example Of Poor Design |
| both are almost never confused. In fact most | | | | In a May 6, 2004 newsletter of the Institute for |
| people who regularly use both telephones and | | | | Safe Medicine Practices a glaring example of |
| computer numeric keypads are surprised when | | | | poorly designed custom keypads was given. They |
| someone points out they are different. | | | | reported problems with IV pumps that had a |
| That is because we learn very quickly which is | | | | decimal point key located near the zero key. |
| which and don't even notice they are different. If | | | | Several cases had been reported of nurses |
| your machine uses a 10-digit keypad, you will | | | | accidentally hitting zero instead of decimal. For |
| need to consider whether your users are going to | | | | example a dosage of 1.5 ml/hour could become |
| view it as a phone-like device or a computer-like | | | | 105 ml/hour! Luckily, the errors were apparently |
| device. If you put a computer keypad on a phone | | | | noticed before any harm came to the patients. A |
| device, you will have a lot of angry users. | | | | simple design change such as moving the decimal |
| The Importance Of Prototyping | | | | point away from numeric keys would have made |
| The example above is a perfect illustration of | | | | the IV pumps safer. |
| why custom keypads should always go through a | | | | Even if your equipment doesn't have the potential |
| prototype phase. An interface design that looks | | | | for harm that a poorly designed IV pump has, |
| great on paper might be a disaster in real life. Only | | | | you still need to consider carefully the design of |
| through in-person, hands-on testing can you be | | | | custom keypads. If nothing else, a confusing |
| sure your interface design is a winner. | | | | interface will lead to frustrated clients who might |
| Prototypes can be produced quickly and easily | | | | buy from your competitor next time. |
| allowing manufacturers to create a mockup of | | | | |