The HP TouchSmart PC

HP’s got an advertising blitz going on for their new touchscreen interface PC. It looks pretty damn cool on the commercials, and I mean come on, is the mouse really the best input device we can come up with?

But the thing is, despite HP’s Hudsuckeresque “Touch the Future Now” slogan, this has actually been tried before. Back in the 80′s. I was a computer geek long before it was cool, and I remember the first time touch screens and light pens were all the rage. So if this awesome futuristic technology is actually over 30 years old, how come we’re still using the shitty old mouse?

Well, let’s try an experiment. Pretend you’re reading this post on a touchscreen. Pretend that you can navigate just by touching links. There should be a whole shitload over there on the right. Spend five minutes touching the links, pretending to navigate around. I’ll wait.

Now, how does your arm feel? Is it sore? Does it ache? Congratulations! You’ve got gorilla arm!

Gorilla arm was a side-effect that destroyed vertically-oriented touch-screens as a mainstream input technology despite a promising start in the early 1980s. Designers of touch-menu systems failed to notice that humans are not built to hold their arms at waist- or head-height, making small and precise motions. After a short period of time, cramp may begin to set in, and arm movement becomes painful and clumsy — the operator looks like a gorilla while using the touch screen and feels like one afterwards. This is now considered a classic cautionary tale to human-factors designers; “Remember the gorilla arm!” is shorthand for “How is this going to fly in real use?”. Gorilla arm is not a problem for specialist short-term-use devices such as ATMs, since they only involve brief interactions which are not long enough to cause gorilla arm. Gorilla arm also can be mitigated by the use of horizontally-mounted screens such as those used in Tablet PCs, but these need to account for the user’s need to rest their hands on the device. This can increase the amount of dirt deposited on the device, and occludes the user’s view of the screen.

There’s an old saying about those who don’t learn from history being doomed to repeat it. Or maybe there’s a marketing saying about how most people won’t remember the failed technology of the past and they might buy some expensive hardware until the lessons are relearned. At any rate, we’ve been here before, and there’s a very good reason these things didn’t catch on the first time.