Tag Archive for 'usability'

A truly uncool armrest design

Back from vacation, having flown a Boeing 737. This lacked the personalized screens seen in longer haul craft but it had a headset jack and a set of volume and channel controls for each passenger. The controls were set in the armrest, in easy reach of the passenger, like this:

Boeing B-737 armrest audio controls

Cool, huh?

Not cool. The two rocker switches for the volume control and channel selector are flush with the surface of the armrest. This means that if you rest your arm on the thing – or if your neighbor in the next seat does – your channel is bound to skip up or down every few minutes. If you watch a movie this can get truly aggravating.

And all they had to do was recess the controls a couple of millimeters under the surface…

Excellent human engineering in the Small Calculator

A century ago Gilbert Small, of Waltham, Massachusetts, invented a compact pocket calculator that is small, effective, and designed with special attention to usability.

Read the new article on my History of Computing site to see what he’d crafted!

The Small calculator

A new way for elevators to crash

Crashed ElevatorWhen Elisha Otis invented the ‘safety elevator’ mechanism in 1852, elevator crashes have become a rare event indeed. But these days “crash” has a new meaning, which Otis couldn’t have foreseen. Consider the elevator in the photo, from the Azrieli towers in Tel Aviv. It has a wonderful new control system with a large computer screen to tell you what’s going on.

And, as you can see in the photo below, it has crashed…

Crashed Elevator controller

Too bad the weary traveler has no way to follow any of these cryptic instructions.

In fact, we run all too often into this situation: a  computer-embedded system that sends admin-level error messages at a user that has neither the ability nor the expertise to address them. A simple blinking red light captioned  “malfunction – call maintenance at tel. 1234567” would at least be actionable!

Guest post: Elevator button usability

Today we have a guest post from our loyal reader George Trudeau of Hyannis, Massachusetts.

George sent me this photo:

Elevator Buttons

And here is the story:

I went to a Doctor appointment and took the elevator up to the second floor office by pressing the great big 2.

When I left the office, I was still thinking more about my appointment than how to operate an elevator, so I pressed the button under the 2, the doors closed, and I returned to my thoughts. Eventually I realized nothing was happening so I pressed the button under the 2 again… It even has arrows pointing to it.

If I wanted to go sideways I might have pressed the right button the first time.

Nice catch! Not only is the up/down direction represented sideways, but the line in the  “Close doors” icon does look like a “1”  in the same style of the “2”. Of course, you have to be distracted to make this mistake… but usability is about ensuring proper user interpretation even when distracted!

The HP150 Touch Screen: a cautionary tale

Not all cool ideas are actually good.

Back in 1983, around the time the IBM PC made its debut, my boss at Intel had acquired a very innovative personal computer: the Hewlett Packard 150.

I remember it well; it was a really cool machine – at least in the context of its day: it had an 8MHz (yes, 0.008 GHz) CPU and 256KB (0.000256 GB) memory, as well as two floppy disks of 270KB each. It also had that solid look and feel that the better companies gave their machines when they could charge thousands of dollars for them. But what made it super cool was the screen, and the ad here shows you how proud HP was of developing it:

HP 150 poster

Photo source: Vintage Computing and Gaming.

The HP 150 had the first Touch Screen I’ve ever seen on a commercial computer. It was actually a regular nine inch green CRT, with a bezel that had holes all around it with IR emitters and detectors in them; sticking a finger at the screen would block some IR rays and tell the computer where you were pointing. And this is where the designers had failed: they forgot that the human arm is not designed to be held in the air, poking at a surface in front of one’s face. The resultant muscle fatigue was known as Gorilla Arm…

That alone was enough to relegate this screen to the junk heap of failed ideas, and touch screens would have to wait for tablets and devices that can lie flat on a tabletop or be held in one’s hand.

Still, you have to admit it was a good looking machine!

HP 150 computer
Photo source: Computer museum, Stuttgart University.


Form contradicts Function!?!!

Sure thing, Form should follow Function… but some designers haven’t heard of that. Like the Sony designers responsible for the two weird design choices below.

Round knobs are round because they need to be gripped and rotated… an optimal design for our opposable-thumb grip.

But the radio below has a round knob whose function is to slide right and left between two positions. There are wonderful switch designs for that, some going back to the Industrial Revolution… and their oblong form reflects the lateral movement. Not here, though…

Confusing Round Knob on a Sony radio

And then there’s this little stereo system I use in my home office:

Sony Stereo System with odd knobs

This has four shiny round knobs, of which one – at the right – actually rotates to control the sound volume. The other three are flush with the panel and are actually two-way momentary push-button switches – you push the top or bottom part of the control for a “click” that might advance the tuning or track up or down. The use of a round form here is an abomination, and each time I use them I go into a tiny cognitive dissonance. Fortunately, the sound quality is good enough to put me in a forgiving mood…

Android vs. Palm: the lost art of keeping it simple

Back then we had the Palm Pilot. It had a gray lo-res screen and minimal capabilities. No wireless, no GPS, no games, just basic PDA funcfions. Compared to the android phone I use now it was like a stone ax. And yet, that old Palm had a key attribute that is long lost: simplicity of use.

Palm PilotA prime example: the “EDIT” button. Take the common task of modifying a memo or appointment. In Android, you have to open the item, and then hit EDIT to enter a mode where you can make your changes. And when you’re done you hit SAVE. Makes sense? Not really. In PalmOS you opened the item and just started typing. Edit mode and View mode were one and the same. Just like a sheet of paper: you can read it and you can write on it as you wish.

It may look like simple matter, but all those extra clicks do add up and clutter the user experience; what’s more, they detract from elegance – that intangible element which calls for keeping it simple!

A wave of the hand

We all know the paper towel dispensers that you crank to get the required length out. The more sophisticated ones dispense with the crank action and use an electric motor actuated by a proximity detector: wave your hand in the air in front of the machine and out comes the preset length of paper with a satisfying whirring sound. Hygienic, neat, and foolproof.

Two paper towel dispensers

But even with this foolproof concept there are different designs. The device at the left in the photo tells you to wave your hand to the right of the paper outlet slot. The one at the right has the sensor centered above the slot’s middle. Why does this matter? because the average person will reach out for where the paper is expected; with the second unit this will trigger the sensor, whereas with the first, it will not. Then you have to start groping and try to figure it out, and maybe notice the frantic effort the vendor made to guide you: the picture of a hand titled “sensor”, the big blue arrow pointing to it, and the text captions that try to make it all clear.

Towel Dispenser markup

All nice and good, but a towel dispenser is not a literary work, and should not rely on texts and explanations. Had they put the sensor in the middle all this would’ve been unnecessary…

Sygnet handsfree design flaws, part 2: Control overloading

Sygnet Handsfree with stickersBack to my Sygnet Bluetooth Handsfree Carkit model BTS600. We saw its problem with cloaking the controls and indicator lamps… but on top of that, the people at Sygnet played a trick that is becoming very common in this digital era: they overloaded the controls and the lamps.

I use Overloaded in the Object Oriented Programming sense: the use of one operator or function name to perform several different functions depending on context.

The Sygnet device has three operating buttons and more than a dozen actions; so each button can do many different things. For example, the “-” button rejects a call if pressed for 3 seconds while the phone is ringing; it initiates voice recognition dialing if pressed for 3 seconds when the phone isn’t ringing; it cancels the voice recognition if pressed until a beep is heard; it cancels bluetooth device recognition if pressed for 6 seconds; it reduces audio volume; it mutes/unmutes a call when pressed concurrently with the “+” button; and it starts a conference call if pressed for 3 seconds while one call is active and another waiting. The other buttons likewise do a great many things; it’s so complicated that I carry the instructions in the glove compartment at all times! Needless to say, the captions on the device merely identify the buttons, not their functions.

The two indicator lamps, meanwhile, are similarly overused: The blue lamp blinks 3 times every 2 seconds to indicate an active Bluetooth link; it blinks rapidly together with the red lamp when the device recognizes the cellphone; it blinks every 2 seconds when bluetooth is inactive; it stays lit with the red lamp during charging, and without it when charging is completed. So now you need a stopwatch to figure out what it means…

To illustrate how excellent this human engineering is, consider its application in a ballistic missile situation: “Hey, Joe, does two blue blinks followed by a long beep mean a 3 second push on button D launches the missiles unless you first tap on button A, or does it mean the Mr. Coffee needs maintenance?”

So, what can we do about this? Well, by now you know my style. At least I could make the cloaked buttons eminently visible…

Sygnet Handsfree with stickers

Sygnet handsfree design flaws, part 1: Control cloaking

Sygnet Bluetooth HandsfreeWhen I got my Nokia E71 smartphone, I also bought a hands-free device for it: the Sygnet Bluetooth Handsfree Carkit model BTS600. This actually works quite well – it wirelessly identifies the phone on my belt when I get in the car, and until I leave the car all calls are routed to this device. Throw in voice recognition based dialing, and it’s convenient indeed.

Still, the controls of this elegant space age device – it really looks like a miniature flying saucer, doesn’t it? – embody some basic human engineering errors, ones that are all too common in other products; we can call them control cloaking and control overloading.

By control cloaking I mean making controls that are all but invisible and indistinguishable from each other. The BTS600 has only four controls: a power switch, and the three marked with +, – and a handset symbol. The user needs to identify the last three rapidly, at a glance, while driving a motor vehicle. So what would you do to make this easy?

I know what I would do: I would design large, obvious buttons, each differing markedly from the others in color (for daytime use) and in shape (for night time driving). Something like the three skyscrapers in the Azrieli Center in Tel Aviv – one round, one triangular and one square, and all impossible to miss…

Not so the good engineers at Sygnet. They made the three buttons flat, and blended them into the device’s surface so elegantly that you can barely make them out – with tiny labels that are hard to read even when parked. And the device’s perfect circular symmetry makes it impossible to locate the buttons by their positions relative to its edges.

Sygnet Handsfree controls

And then there’s the matter of indicator lights. The device has two lamps: blue and red. You’d expect these to be visible from all angles; which would be the case if they protruded outside the casing. But instead they are sunk deep inside, under the clear plastic ring around the speaker grille. Again, very elegant – but quite invisible unless you look straight in.

Don’t miss the control overloading post coming up next!