[Sigia-l] When will you buy one?

[Karl Fast]

> Huh? People complain mostly of RSI pain in the wrist (and forearm) when
> working with computers, with which handwriting has nothing to do.
>
> The prediction here is that vertical touch surfaces will move the pain to
> the shoulders.

I made my point very poorly. Let me try again.

These surfaces *might* cause RSI, but there is no guarantee they will.
Moreover, it depends not just on the interaction device but also on
how people physically perform the interaction.

My writing example tried to illustrate this. Writing with the fingers
is far more likely to cause cramping and tiredness than writing from
the shoulders. So an interactive surface may not move pain to the
shoulders. It may, but it may not.

It also depends a great deal on how people move their fingers, hands,
wrists, shoulders, etc, and not just on the type of device they are
interacting with (though that is important). Just as there are better
and worse ways to write with a pen, good technique and bad, there will
be better and worse ways to physically interact with these surfaces.

Running is an interesting example. In a given year, about 60% of
people who run or jog on a regular basis (say three times a week)
experience a running induced injury that is serious enough to prevent
them from running. But there are several different running techniques
and some of them, notably Chi running and Pose running, dramatically
lower the rate of injury. It is often claimed that running causes knee
pain or shin splints. A more accurate claim is that certain running
techniques are more likely to cause these problems than others. Good
technique can reduce these problems, even eliminate them. I learned
chi running last fall, and my knee pain has since vanished.

Coming back to interactive surfaces, my point is that while physical
pain can be caused by poor ergonomics, it's unfair to blame everything
on the artifact. Subtle differences in the physical techniques we use
when interacting with the world can make a huge difference.
Handwriting and running are two examples from my own experience.

Still, ergonomics can make a huge difference. Typing used to give me
severe wrist pain. When I switched to a split finger keyboard the
problem vanished overnight.


-- 
--karl
http://www.livingskies.com/