Month: July 2018

Human-machine interaction and the usability conundrum

In this day-and-age usability shouldn’t be the issue it is. There are usability experts out there and frankly how hard is it to make this usable? Hard it seems. Makers of physical tools seem to get it right most of the time, in fact some designs work so well, they haven’t changed in eons. So why is it so difficult for people to get tactile usability right in devices… devices like self-checkouts, and washing machines? They aren’t new of course, they have been around for years, and the secret to getting them right is easy – *test* them on real people. There shouldn’t really be any excuse.

Every day I encounter everyday machines someplace whose use is just not very intuitive. You should be able to look at a machine and figure out how to operate it without reading an operating/instruction manual (were they to be well written as well). I’m not a great usability expert, but I know enough about the design and usability of hand tools to know how easy it would be to design a machine interface that actually works well.

Here is the interface to my Miele dishwasher. It is inherently quite simple, and is comprised of three “zones”. The first zone is the cycle selection knob. Yes, it’s a physical interface, but I almost prefer that to one where I have to set the cycle each time I turn the machine on (like my washing machine) – in reality I use one particular cycle consistently (Economy), and the others only on occasion. The second zone is the indication lights, which tell me where in the cycle the machine is currently at. This is the one place where the terms used could be a little clearer, because the lights go from Rinse to Drying, with no indication of washing per se. I would have modified Rinse to Washing (this could actually be a translation issue from German to English, as the German word might encompass both actions).

The last zone involves the error indicator lights. This is nice and simple and deals with the most relevant issues encountered by the dishwasher. Is there a problem with the water intake or drain? Or is the salt reservoir or rinse aid empty. The dishwasher does have both an On/Off button and a Start button, which I find odd, but it does prevent the dishwasher from accidentally starting a cycle.

Even their new washing machines and dryers offer good, yet simple usability. It makes use of a physical rotatable knob to select the appropriate program, and an adjoining panel to select such items  as water temperature and extra options. e.g. pre-wash, soak. Each program does have a pre-programmed set of values, so it is easy to set the program, and start the machine. It even has a “MobileControl” setting to explicitly allow control of the washing machine from a mobile device – if you want this.

Physical interface buttons offer familiarity to the user, and likely less chance of some electronic component failing.