This unique speedometer uses a GPS for speed tracking, and displays your speed with an RGB LED. While as-programmed the speed is displayed only as stopped (red), +2MPH (yellow), +9MPH (blue), or +13MPH (green), this could be expanded to a more granular form if you so desire. Also, the GPS unit could be used to show other stats, like how far you are from home, and the bike has a white flashing mode specifically for night visibility.
Step 1: What You'll Need
For this project, you'll need
- RGB LED
- Arduino Pro Mini (Amazon)
- GPS module (Amazon)
- LiPo Battery
- Charging module (I used something like Edition 1 with a micro connector, but I'd recommend Edition 2 instead, listed here (Amazon) if it will fit)
- Hot Glue
- Zip ties
*Note that the charging module is not shown in the diagram, but will go between the Li-Po and Arduino Pro mini
Step 2: Print, Solder, Stuff
Solder per schematic in previous step + Li-Po charger.
Everything will be a tight fit, and you'll need to secure buttons and charger as seen in the video. Also, feed zip ties through the four rectangular holes toward the middle to facilitate handlebar installation later.
Step 3: Program
Step 4: Install and Use!
Wrap zip-ties around your handlebars, turn it on with the button on the bottom and start riding. It may take some time for the GPS to get a good lock on satellites, but after this, you'll be able to look down for an instant to see what speed mark you're at, or provide lighting.
More background on this project and using a GPS module with Arduino can be found in this article.
Note links to Amazon are affiliate.