Last Friday, I became a lab rat. The wife of one of my officemates was looking for subjects for her experiment in motor control, so I decided that I would volunteer. Later on, I read that on their website that “all tests are non-invasive and usually not painful” (emphasis mine). That’s when I wondered what I had agreed to!
As it turned out, there was no need for a concern. The experiment took one hour, plus set-up time. I had to walk on a treadmill with motion capture system tracking my posture and gait. There was an image projected on a screen which shows squares for each foot that I had to step on. If you have trouble imagining this, just think of a very simple version of Dance Dance Revolution with only two buttons.
It was a bit unnatural for me to walk and try to hit the targets while looking forward. Nonetheless, it was quite fun. For this particular experiment, there was no electrodes that I was connected to – it was pure motion capture.
I didn’t ask too many questions about the test, as I thought that would introduce some bias and may influence the objectivity of the test. But as far as I could deduce, the first part of the experiment was designed to test how quickly I could adjust to the pattern in the positioning of the squares, either consciously or unconsciously. I did very badly in the one that had a random pattern, which is exactly what should have happened.
The next part of the experiment was a bit more interesting. This time, there was an asymmetry in the speed of the squares. This is to simulate a split-belt treadmill (each belt corresponds to one foot and can be controlled independently). The resulting motion that I ended up making kinda reminds me of a limping gait. So I guess she wanted to repeat the first experiment for people with a (controlled) limp.
All in all, I spent about an hour walking on the treadmill. There were times during the test that I thought I was walking like Paul Atreides of Dune, having to break my natural walking rhythm. But unlike him to avoid attracting sandworms, I did it to hit the squares.