Phoenix is not the best place for kite flying. If we happen to get a breeze at all, it's often too light or too gusty to support kites. I've been trying to catch the perfect wind to fly my little dual line delta kite, but I keep missing the best hours of the day. I decided to build a little alert system that can help me recognize when the best conditions are present.

A few days ago I managed take note of the wind speed that I needed to launch. Somewhere around 14mph is the minimum for my kite, anything over 24mph is probably too harsh. I looked up those wind speeds on the closest private weather station to my apartment using wunderground.com. Turns out that Weather Underground also provides xml feeds for each of those stations.

Using C# I built a little application that downloads the latest weather xml and parses out the wind speed plus a few other details. I included options to set the wind's optimum and minimum velocities as well as the refresh rate. The current wind speed is compared to the velocity settings and scaled to a percentage value. 0% means you have no chance of getting off of the ground, 100% means the current wind matches or exceeds your optimum. Now I needed a way to show off the data.

A notification pop-up or ding on my computer would have been sufficient, but I wanted something more symbolic. I hooked up a small servo to a BS2 and added code to my program to output that percentage value over serial every time it refreshes. The basic stamp watches for an update and moves the servo according to the value. Mounted on the end of the servo is a wire with a little paper kite its end. As the the wind approaches the optimum speed the kite rises into the air. Pretty symbolic huh.

Now go fly a kite!

P.S. I'll let you know when and where the application and example microcontroller firmware is available for download just as soon as I work out some bugs.