Last night I began working on ordering the base for the project. Some of the decisions that needed to be made was how to attach the base to a tripod, how to make sure the base can turn freely on the top of the tripod, and how to attach the yaw stepper motor to both portions of the base plate.

After a bunch of research it was decided that I should make my own shaft connector. This needs to connect the shaft to a base plate which is 90 degrees away. For this I will use a 0.25" thick aluminum sheet cut to 1.5"x1.5" with a hole drilled sideways and tapped to use a 4-40 set screw. Since I was doing this already, it made sense to drill and tap a similar sheet of metal with a single 1/4-20 tapped hole to mount the project to the tripod. These aluminum sheets will be screwed to a sheet of ABS which will attach to a lazy susan. All parts are on order but the cheap ABS won't arrive until July. Pictures will be posted once assembly begins.

While I was at it, I also ordered some power supply materials for the project. Because my caving lights use 18650's I looked into whether they would work for the project. For $10 its possible to get a 4 pack of these batteries that have a 2000mAh capacity (measured by reviewers). They also have been verified to maintain more than 3A of current. Since my project uses 0.7A per stepper plus 25mA for the Arduino, plus up to 250mA for the SF30-B sensor, I am going to be using less than 2A of current as a rough estimate. That means these batteries will be able to supply enough current and should run at least an hour. Good enough for the prototype model.

I already have some switches and assorted parts at home to make this work. Once all the materials arrive I should be able to make the base plate and to attach the first stepper, batteries, and Arduino to it. It'll still be on a breadboard but you have to start somewhere.