I suspect that may even be the one Andrew used. I have used it before as well with a similar design as the one Andrew posted, but as I wrote, I had difficulties taming the torque.
I have not found a gear generator yet that allows me to adjust the dimensions for different diameters and different gear ratios so I gave up on that approach and moved to my simpler, but less elegant solution. Which works perfectly, really, but is not nearly as compact as Andrew's.
My worm and ring gear are in fact Globoids generated with OpenSCAD. I am hesitant to share the original STL files at this time as everybody I have shown this to has encouraged me to market it. But I do encourage others to take inspiration from it. I'm honestly surprised I have not seen anyone else use this mechanism yet.
I used the following script to generate a custom set that I added features to in other 3D modeling software. www.thingiverse.com/thing:2776688
*But this is an updated version if the script that may be better. www.thingiverse.com/thing:4197625
You will want to unhide the Customizer under the View Menu. And I had to scale down the gears it created to the right diameter.
My latest creation, a NEMA17 short body stepper motor-driven autofocuser for my Explore Scientific 102.
I prefer gears over belts,
This design is easy to print and can be attached without any modifications to the telescope.
The large gear fits directly on the fine focus knob and is held in place by three screws that lightly clamp it to the knob. Rocksolid.
I have the wave share PI hat running on astroberry. I followed all the instructions for installing it. I see the xml file indi wmh in the usr/share/indi directory. I can not get it to show up when I edit the ekos profile for indi devices. Any ideas??
Second, why isn't this distributed as paart of the indi library?
Re why it isn't in the library, I have no idea. It's a terrific DIY solution, the driver Just Works and so does the Waveshare board. Heck, the board is cheaper than buying the parts to solder together a myFocuserPro, and you can be running 15 seconds after you open the package.
Restart KStars? That's about all I can think of, if the file is there, perms are OK, and it has Kevin's content, it ought to work. It's unlikely that the XML files live in a different folder, but you could try picking one of the other drivers that's in the Ekos distribution and searching for it everywhere in the file system with:
sudo find / -name name-of-file.xml
where "name-of-file" is the other driver filename, like indi_wmh_focuser.xml.
If you find the file in another place besides /usr/share/indi, you could copy indi_wmh_focuser.xml there too and see what you get. Beyond those two ideas...I got nothin', I'm afraid.
Hmm, well that's odd. Sorry for asking a couple silly questions, but I need to get them out of the way. Did you restart KStars after installing the Waveshare driver? Are you running KStars on the Raspberry Pi, or on another computer over the network? If it's the latter, then you'll have to install the XML file on the remote computer as well.