Sky Tracker V2 (Do Not Make It Though)

I wanted to design a sky tracker that is easy to make, and is not as bulky as barn door sky tracker. At least I made it not bulky. EASY? well that is a whole different story. So my idea was very simple achieving a extremely high gear ratio in smallest possible and what is better than worm gears. In short it is a simple worm gear based tracker that is laser cut using MDF. Unfortunately I didn't get a chance to completely test it as the gears I designed were not the best. I do have attached 3d gears that should work. This instructable is not a one stop solution (hopefully soon becomes one) but a design I tried out and worked decently. I will take you behind the design process, and share my thought process. So let's go.

If you have previously made Barn Door Sky tracker, You have most of the stuff already.

Total supplies include.

1. 28byj-48 stepper motor
2. ULN2003
3. Arduino or any other microcontroller
4. 1/4-20 Bolt to mount camera
5. Lots of M3 bolts washers and nuts
6. 3 M8 Bolts
7. Weights (dependent on camera)
8. Laser Cut MDF or better Acrylic (I had to use 2 4mm sheets, single 8 mm sheet will be stronger)
9. Bearings (608)
10. Will to experiment.

So first things first, choosing the motor, as it will dictate lots of decisions we make in the future. We need a decent motor that is highly precisely controllable and a decent torque. What is better than a stepper motor with extremely accurate control over RPM. I chose 28byj-48 stepper motor due to its high gear ration built in. It has a net steps per revolution of 2048. It gives us a lot smoother motion at a relatively low cost! I modified it to make it bipolar that gives me higher torque but that is not compulsory. You can use ULN2003 motor driver to drive it.

Connection with Arduino is pretty straight forward. Just follow the schematics and you should be good to go.

The Design process revolves around two worm gears.

A small enclosure is designed to house the gears and keep them at place.

Feel free to play around the design on tinkercad

https://www.tinkercad.com/things/f582KdIKbuw?sharecode=fbGBuMziW-tkCcfzwKgUxDgPEDPSETVcTnDYqhvJMtM

https://www.tinkercad.com/things/iZ6fidueILA?sharecode=4dg4vrv5linbdenWLsQMWDPBj13pbU9fvLbfEgTz1KA

https://www.tinkercad.com/things/jmjaYwEJ8Qr?sharecode=BdyrJpDefpjAqKb3cy0pJbtINAb8rzfc2GvMRXQDJT0

Initially I was using laser cut gears but honestly it is a really bad Idea and I wont suggest anyone. I used M8 bolt as a worm shaft and laser cut the gears. They lacked the required grip and soon the gears were completely destroyed. I suggest going for a 3d printed gears. Feel free to download it and remix according to your needs. I haven't tried these gears but I am pretty sure they will work. If you do use, let me know how it goes.

Not gonna lie, these turned out better than expected. The mounts are really strong and sturdy and I wont mind mounting my camera on it. (your mileage may vary)

After the design process was complete. I cut 4mm thick MDF (Prefer 8mm acrylic) and started assembling it. Some joints were a little difficult to add but after a little bit of tinkering everything worked out amazing except of course the gears.

Thanks for stopping by and giving it a read. In case I missed something please let me know. I would love to revisit this project and make it better.

Also here are some great tools that really helped me out in my journey.

https://evolventdesign.com/pages/spur-gear-generator

https://en.makercase.com/#/