Thinking of how to utilize the many openbuild components to remote control a 10" dobsonian telescope. Only 2 axis of movement - a vertical component that rotates around the Z axis and a pivot point around the X axis. See attached image for reference. The goal is only for viewing, not astrophotography, and to be able to share with family and friends in the comfort of a temperature controlled room on a large screen TV, with drink in hand. During the winter months in the mountains - not a pleasant experience for 5 individuals waiting their turn to view through the one eyepiece. Open to all ideas and suggestions.
there must be many DIY systems on the web for the controller diy telescope control stepper - Google Search for the mechanics I would use belt drive, probably 2 stage reduction from motor to axis, you need very small, smooth movements.
I think the mechanical arrangements will be the real challenge. Any drive system acting on the existing axes will need to move slowly against the friction built into the bearings (so that they hold when positioned by hand) unless you were to ditch the Dobsonian mount and build a new alt/azimuth mount with computer control in mind. As you may be aware, the usual solution to this for a Dobsonian telescope is an 'Equatorial Platform' - a device that fits under the base of the telescope and slowly tilts around the celestial pole. This is the site that I've bookmarked for my build (when I get around to it) - I would build something like his design, but I'm at ~ 60°N. For Colorado (from your profile) at ~40°N you may need to go to a design with two circular segments to keep the size down - there are several linked from his page. I think a CNC router would be ideal for cutting out the segments accurately. Telescopes and Deep Sky by Reiner Vogel
Thank you OpenBuilds team and Misterg for your ideas and the link. Soon I will share one of many possible solutions I am considering. I will first construct a full size model before I modify my telescope - a proof of concept to highlight any constraints I missed. Thanks again.
I have a couple of ideas. The rotational function should be a simple solution, only a couple of variables. Belt drive or gear drive and the final drive ratio. Also need to consider the bearing pack, something similar to a lazy susan design or an enclosed thrust bearing. Either type will require the unit to be sealed from environment. To control the altitude - I have a couple different ideas. A lead screw affixed to a hard point that is currently the handle to maneuver this scope. Secondly, a curved rack and pinion attached at the bottom end of scope. I have attached the ink sketches to help illustrate my thoughts. I will draw this up in CAD to nail down some measurements and angles of motion. Open to comments, ideas and improvements.
Sign me up, following this thread keenly - I only have a entry level reflector Celestron 114EQ - but if you do get this going I am totally going to do it too. Setting up the equatorial mount every time is probably the main reason we don't set it out nearly often enough over the weekends. App based pointing would up the wife acceptance factor enough I might be able to get budget to upgrade (; It is actually her hobby though - but I do enjoy it too. So anything that makes things easier is a win! Automated tracking would be the big win though - keeping observations in view is hard with the kids bumping on the flimsy stock mount and the earths rotation too I think the curved rack and pinion makes most sense to make the future firmware development easier - essentially making an AZ mount - but the curved rack means less math. Home + steps per deg = absolute position. Actuators would need extra math to translate to degrees Getting a custom cut rack these days is super easy with services like SendCutSend I will also dare pop in a shoutout for a local aquantance of mine, Willie Koorts > Youtube Channel - lots of cool content on his channel - not amateur level, but you will enjoy it. He works at a local observatory (SAAO) so access to lots of cool sites and projects
Thank you for the link - I subscribed. To keep everything simple - I am only looking for control, no tracking abilities. I live in a perfect location, mountains, limited or zero light pollution from very few neighbors. Another reason I am tackling this challenge - trying to revamp the local delnorteobservatory.org I think I could increase interest if one was able to view the stars in the confines of a temp controlled room with a mocha in hand. Regarding the custom rack design - I took a part time job with a metal fab shop, which happens to have a 4 kW fibre laser in its arsenal, nice having good tools within reach. I was also thinking of using the flex plate from my old small block Chevy, cut in half, have a few sitting in bottom of a toolbox. My shop is not heated at this time, therefore the prototype will have to wait for warmer weather. Next winter shop will be heated. I must also consider portability, ease of assembly and breakdown. Thank you for your input.
