Attempt at cheap homemade version of Harmony

[Oran]

Glad you shared more about your shifter setup I was interested in how you had done it. I really like the simplicity of your system, probably win in terms of reliability. Definitely has a big advantage in terms of energy efficiency and battery life only switching the servo motor on when needed. If I hadn't been wanting to learn about Arduino programming and didn't want the challenge of automation I would have done something like yours. Couldn't resist the temptation of exploring some of the possibilities opened up by removing the mechanical link between hub and shifter.

Have been working recently on getting the system into a more permanent and waterproof state.
The handlebar shifter is finished complete with real N360 planet.



The 11.1V 3.2Ah lipo battery, 5V power supply and Arduino are all wired and taped together so they fit in the saddle bag. I'm using a telephone extension as the link between Arduino and handlebars.



The servo is now in a waterproof box. I was a bit undecided about where to mount it on the bicycle. I wanted to minimize the cable length and mount it close to the shift interface. It would have needed a metal frame to support it and its liable to get knocked in that location. Also would have created issues with wheel removal if it wasn't above the shift interface. So I chose the top of the seat stays instead. The length of the cables is slowing down the servo so I need to get better quality or upgrade the servo.



The upgraded 5V power supply is only powering the servo at the moment. The Arduino is using its onboard regulator so is wired direct to the 11.1V lipo. This seems to have improved the signal getting to the servo as its spending much less time micro adjusting it's position.

The next stage is to install the reed switches and probably the pulsed DC to voltage circuits. Then the Arduino programming can begin.