Nike + iPod = 0
By Julien on Wednesday, November 29 2006, 15:59 - Equipment - Permalink
This morning I had the chance to try the Nike + iPod "Sport Kit". Not that I would buy one, but there's one in the lab for wireless body sensors testing. It's basically a wireless bluetooth-like accelerometer you fit in (on) your shoe and a receiver plugged in the iPod. A quick look on the internet before going for my run and I found the blog of an iPod aficionados. He successfully used the sensor with non-Nike shoes and without pre-calibration but managed to get a pretty good accuracy (about 1% to 2% error).
I then confidently ran 2 loops in Hyde Park. The distance is about 6.3km, measured on several maps, with several tools (ruler, curvimeter) and on GoogleEarth by several persons:
After my run, the iPod displayed (*):
Hmmm, it reads 8.53km, when I expected ... 12.66km (2*6.33) ! That's an amazing 33% error ! One of my colleague faced a similar error. Even more worrying: some also reported a wrong recorded time. Of course, I didn't calibrated it and I didn't use the Nike shoes. But well ... that's just as good as a good old mechanical podometer. I guess they don't do anything more clever than counting the steps. I believe that with a Walkman, a podometer, a watch and a couple of transistors something more functional could have been designed 20 years ago ...
Our aficionados must be very naive (or well paid) to be "very thankful that Nike and Apple made it possible to use it with alternative running shoes" ... Not only you have to buy the gadget anyway, but as it's not very convenient to wear, you'll probably buy some compatible Nike shoes next time.
Ultra Christmas gadget.
(*) yes, date is not set properly
EDIT (18/01/2008): this is actually not an accelerometer, but a simple contact sensor. Therefore it can only count your steps - this is a basic podometer... See Sparkfun for example.
I then confidently ran 2 loops in Hyde Park. The distance is about 6.3km, measured on several maps, with several tools (ruler, curvimeter) and on GoogleEarth by several persons:
After my run, the iPod displayed (*):
Hmmm, it reads 8.53km, when I expected ... 12.66km (2*6.33) ! That's an amazing 33% error ! One of my colleague faced a similar error. Even more worrying: some also reported a wrong recorded time. Of course, I didn't calibrated it and I didn't use the Nike shoes. But well ... that's just as good as a good old mechanical podometer. I guess they don't do anything more clever than counting the steps. I believe that with a Walkman, a podometer, a watch and a couple of transistors something more functional could have been designed 20 years ago ...
Our aficionados must be very naive (or well paid) to be "very thankful that Nike and Apple made it possible to use it with alternative running shoes" ... Not only you have to buy the gadget anyway, but as it's not very convenient to wear, you'll probably buy some compatible Nike shoes next time.
Ultra Christmas gadget.
(*) yes, date is not set properly
EDIT (18/01/2008): this is actually not an accelerometer, but a simple contact sensor. Therefore it can only count your steps - this is a basic podometer... See Sparkfun for example.
Comments
Ahh, but actually, that's because the ipod warps you in another dimension, where distances are shorter!
Big brother in your shoes ?
uwnews.washington.edu/ni/...
I use my Nokia 6110 Navigator with GPS and the software Nokia Sports Tracker. When I run or when I ride my bike, it shows the distance (99% accuracy), heigh per distance, speed per distance, and I can download the track to the computed and see it in Google Earth. There's something better?
To measure distances, I've also tried the Polar RS800sd based on a similar technology: see this entry, as well the Garmin Forerunner 305 GPS watch. They are both clearly much more accurate.