I always thought it was not possible to have a speedometer like device while speed skating on indoor tracks for several reasons. Especially lack of GPS coverage and no wearable device for viewing speed and lap times. The MYLAPS (http://www.mylaps.com) service, a transponder based timing system, solves only part of the equation. The MYLAPS service provides a website with close to real time data of the transponder. The website or even smartphone app (only for iphone) type of data presentation may be suitable for bystanders or coaches. It does not provide a solution for skater itself.
But times have changed. With the arrival of the Pebble SmartWatch (http://www.getpebble.com) a usable speedometer to be used by the skater has become available.
The only required part to make it work is something that ties the Pebble and the MYLAPS service together. And that something is a program that:
- Polls and scrapes the MYLAPS practice results pages. Unfortunately MYLAPS does not provide some kind of data API which means that the webpages presented to the user are scraped to extract data.
- Send an event to a Pebble notification service. For instance Notify My Android and Notify My Pebble.
A minimal implementation in perl (very handy for screen scraping) is not attached to this post, but is availble on request. The script starts and endless loop in which the practice results page for a specific track and transponder are polled each five minutes. When activity has been detected (a new laptime entry for the transponder), the polling frequency is increased to each 10 seconds. Each new laptime entry is sent to the Notify My Android notification service, and shortly after that arrives at the Pebble. In practice this means that approximately five to ten seconds after passing the finish-line (which contains the MYLAPS detector), a notifcation with the latest laptime is received at the Pebble.
A sample output display (low quality picture alert) is shown below (it is not possible and very unwise to take a screenshot while skating). Today I did my weekly skating training with the speedometer enabled. The experience was very cool. I could almost instantly see the last laptime after passing the finishline.
Next time I think I try to wear my pebble on my right arm instead of left arm. When track skating, the left arm is mostly lying on your back, and the right arm swings at least during corners, providing a good opportunity to readout the results.
Good improvements are a dedicated watch-app on the pebble that provides larger digits and additional notifications through vibration (fastest lap sofar, number of seconds slower/faster than goal), etc. And in theory the polling app could run on the smartphone itself instead of a remote server. On the other hand, a remote server reduces that amount of wireless data being transferred.
I would assume that the number of Pebbler that own a MYLAPS tracker ID is very, very low. This means that my motivation for building a public version of a Pebble MyLAPS bridge app is purely based on my own needs. So, please let me know if you happen to own a Pebble and a MYLAPS