Dissecting a Sport Kit Sensor

SparkFun electronics has a nice write-up on dissecting a sensor. The article has lots of great photos and schematics. We also have an older article discussing why apple chose to use a piezoelectric sensor.

Thanks to Jeruim for the link!

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Nike Amp+ Remote Control Watch

The Men's Health 2007 Tech Guide released some details on a new Sport Kit accessory -- the Nike Amp+. The Amp+ is a wristwatch-based remote control for iPods equipped with the Sport Kit. With the remote you can browse through your song library, choose new tracks to listen to, and view your running times. If you're a serious Sport Kit user, this sounds like a great tool. No more fumbling with your Nano to change tracks or see run info! The Amp+ will cost $80, but no release date has been announced yet. [via]

How does the sensor work?

One of our readers, Allen, wrote in to ask how the sport kit sensor works. Recently I stumbled across a FAQ by Apple that explains a few things:

How does the sensor know how fast I am going?

A sensitive piezoelectric accelerometer monitors your footstrike when you walk or run and determines the amount of time your foot spent on the ground. This contact time is directly related to your pace.

With my seldom-used electrical engineering background, I have to agree that Apple made a great choice for a sensor for three reasons:

1. Price - Piezoelectric sensors are very inexpensive and simple devices. For example, a basic piezo shock sensor costs less than a dollar from Digi-Key.
2. Battery Life - Piezo sensors can be integrated into a very low-power design. Battery life of the sensor has been a main concern of users. It looks like Apple has done their work and the sensor's battery should outlast five pairs of running shoes.
3. Accuracy - By measuring the pressure of each step, the sensor should be able to measure the approximate pace of the runner. Apple claims that the sensor will be accurate for most users out of the box, with no calibration.
   

Previously many people, myself included, speculated that it might be possible to simply strap the sensor onto the laces of an existing pair of running shoes. This was based on the idea that the sensor would use a motion-based accelerometer to measure steps. However by using a shock-based accelerometer, the sensor must be placed underneath the foot so that it will feel the shock of each step. There have already been reports of hobbyists cutting holes in their existing running shoes for the sensor. So far, it seems that they've succeeded!

Some Great Photos of the Sport Kit

AppleInsider has taken some great pictures of the Sport Kit:

iLounge also has a few good photos, including some of the clothing and the shoes:

The Sport Kit wireless transmitter thankfully looks very small. There's one thing that definitely has me excited -- the clothing with not only a holder for the Nano, but also holes for headphone wires. In the picture above, you can see a hole for the wire just to the left of the Nano. When running, the biggest annoyance for me isn't the iPod itself, it's the headphone wires. The wires swing back and forth, often pulling on me and getting in the way. I typically run the headphone wires through the sleeve of my shirt, but that only marginally helps. The new clothing may be just what I'm looking for. Not to mention that the shirts look very slick.

Launch Parties Galore!

Today Nike and Apple hosted large launch parties in NYC, Chicago, Los Angeles, and Houston. They included concerts, sports stars, and of course -- running. AppleInsider has more details on the launch parties.

Available Tomorrow!

Nike and Apple announced today that the iPod Sport Kit will be available tomorrow! It's been available for preorder since its announcement in May, however tomorrow it should be available in retail stores. Two styles of Nike shoes compatible with the Sport Kit will be available sometime in July, the Nike Air Zoom Moire+ and Nike Air Zoom Plus+. Of course the iPod Nano has been available for purchase for quite some time. :) [via]