Usability for Embedded
Designers of embedded
systems face a greater challenge than software engineers developing
for the desktop. On the desktop the environment has been defined—whether
the platform is based on text, MS-Windows, or X-Windows. An embedded
system may be using a piece of hardware for input or output in
a way that it has never been used before. Standards of ease of
use are also higher. On the desktop, the developer can make the
reasonable assumption that the user is familiar with the computer.
An embedded system is often making every effort to hide the fact
that it contains a computer. A desktop application will be compared
to other applications, while an embedded system will be compared
to tools—try competing with the ease of use of a hammer. When
you need to solve some of those challenging usability problems,
some of the links below might provide some inspiration.
My article, Designing
User Interfaces: What Does the Customer Really Want? discusses
usability issues in the design of embedded products, and also
addresses the engineers role in the process of making a product
Postscript copies of
much of Ben Sneidermans Sparks of Innovation book are available
Brewester's homepage contains interesting information on the
use of audible cues in the user interface. This can often apply
in embedded systems that may have a very simple visual interface,
or the user may not be constantly looking at the device. These
audible cues are called 'earcons'.
A number of usability
articles are available at the http://www.ergogero.com
page including information about aging, medical errors and liability,
digital television and a number of other topics.
I have reviewed some
books on usability
on my Bookshelf.
There is and interesting
storey of the user interface flaws in the cockpit of the plane
that John Denver died in: http://www.asktog.com/columns/027InterfacesThatKill.html.
Sorry, fans, I do not have any MP3 links! Apart from that article
the rest of http://www.asktog.com/ is well worth a read.
The FAA Human Factors
Design Standard is .pdf download available from http://acb220.tc.faa.gov/hfds/default.htm.
Lots of it is just common sense, but it can be thought provoking
to go through lists like this and consider where your design may
be failing - simple things like "Help windows should not
obscure the task that the user is working on" is obvious,
once it has been pointed out.
There is a great set
of pictures of bad user interfaces at: http://www.baddesigns.com/.
Many are not electronic, so they are not strictly embedded systems,
but it still makes for some very educational and interesting browsing.
There is a set of usability
papers available at http://www.useit.com/alertbox/,
mostly written by Jacob Nielsen. Many of them are web oriented,
but others address PDAs and other embedded devices. Well worth
Research and Development Center located at the University
of Wisconsin-Madison provides a vast array of information on design
with disabled access in mind. The site covers embedded systems
in areas such as information kiosks and consumer electronics products,
but it also covers a variety of other areas such as building design
and the design of hiking trails and recreation areas. There are
also guidelines on designing accessible web sites. Well worth
a browse if you are designing a program or a device that is going
to have a wide user base, since some of that user base is going
to be disabled - unless you have excluded them by not considering
them in your design.