How to Measure the Earth’s Rotation With a PlayStation Move
The PlayStation Move is the most accurate form of motion control for video games out there, but no one really thinks just how accurate. With some computer knowledge and some engineering spirit, you too can make this scientific experiment a reality.
The PlayStation Move is definitely an unbelievable piece of hardware, for end users and developers alike. While officially licensed Move drivers for the PC may still be a while off, it doesn’t mean that people can’t develop their own software for it. This time around a group of people at PABR.org did some tinkering to replicate a 150 year-old experiment using your favorite piece of gaming technology. Using custom-built Linux drivers, a 45 RPM turntable, 25 meters of electrical wire and a power source, these guys were able to measure the Earth’s rotation using the PlayStation Move’s internal accelerometers and gyroscopes. This is actually a similar method that nuclear submarines and underground drilling teams use to navigate deep below the Earth’s surface. Check out the video demonstration of the entire procedure here.
There is definitely some crazy science, math, and electronics knowledge going on in there, but it’s still cool to watch even if you don’t understand exactly what’s going on. It’s interesting to note that the Move’s components weren’t accurate enough to do exactly what they wanted, as the MEMS gyros suffer from bias drift, so it required some additional engineering to work around that. But why does the Move suffer from this accuracy problem? It turns out that if the controller WAS that accurate, the internal gyros would be classified as missile components, according to the International Traffic and Arms Regulation. To quote the website, “This is why we can’t have nice motion tracking.”
The PABR team documented the entire process on their official website, where you can find more details, the source code, datasets and results of the experiment. Their YouTube page has a more concise description of the process. It’s pretty amazing what people are capable of, isn’t it? Also, it just goes to show you why controllers are still a good idea.