Making a Speed Vest

When I got volume 19 of MAKE magazine I saw a project that I immediately wanted to build. Called the Speed Vest, it is a cycling vest that shows your speed in glowing neon as you pedal. I like to bike and I wanted to start an electronics project, what could be better?

Here is a video of Speed Vest in action:

I figure this will look pretty cool on a group ride! But of course…there are some things I want to change.

• The right digit has only odd numbers, meaning that the precision is 2 mph at best. Not good, especially since the code provided always rounds down (!) — I don’t want my friends to think I’m slower than I already am.
• The vest electronics are attached by wire to the wheel sensor on the bike. If you get off the bike and forget to take the vest off, the electronics will tear (the authors say this has happened three times already).

For the first issue, I am going to try and see if I can get 0-9 attached on the right side without becoming too bulky. The authors managed 6 digits on the left (which is unnecessary given my speed, even downhill) so I am hopeful that I can get all or almost all of the 10 digits on the right side.

A partial solution to the second problem is to put a quick disconnect on the wire. But the ultimate way to go is wireless. Especially since I already have a wireless wheel sensor that does a great job: the one for my Garmin 705. I will cover the details in another post. The first version of the vest will be wired, but I am altering the design to leave the hardware serial ports free for future use.

Tags: speed vest