Topics

Showcase: Built With OnStep

Khalid Baheyeldin
 

I started a new page on the Wiki to showcase what users have built with OnStep.

https://groups.io/g/onstep/wiki/Showcase%3A-What-Users-Built-With-OnStep

If you did build a controller with OnStep, please subscribe to the mailing list, and post description and images as a reply to this message. Or if you have a web site, post the information and pictures there, and reply with the links.

Roman Hujer
 

Hi all, I've already built two OnStep controllers for my telescopes. Details and other accessories are here https://www.thingiverse.com/RomanHujer/collections/onstep

Roman

Raymond Collecutt
 
Edited

Here are two of my mounts. The Dob is a 20" f3.8 built by myself including the mirror, the other is my Tak NJP. The NJP was a Temma 2 but in this day and age it was missing so many other functions that Onstep offers that I just couldn't resist. The mount has much nicer DEC guiding with the belt drive vs the stock 18/1 gearbox that has a lot of backlash. Slewing speeds have tripled also which is nice and after a three star align(can't do that with a Temma mount) it's goto's are amazing. 

https://www.flickr.com/photos/46302893@N02/albums/72157666357957718

Khalid Baheyeldin
 

Thanks Raymond.

Added to the showcase page on the Wiki.

Keep them coming folks ...

John Scherer
 

Great build!  Love the pictures.

alain
 

Hi Gintautas,


very nice work!

I like the solution for the gear housing, cheap, light and easily accessible.

I am planing to make a fixed station also and your work gives me some ideas about on how to realize the concrete pier.


Regards



Le 08/04/2018 à 22:21, Gintautas Drazdauskas a écrit :

Hi there,
I am Gintautas from Lithuania.
At first I want to say a lot of thanks and to pay obeisance to the Howard, Khalid and everyone who collaborate creating and developing the Onstep project. It is fantastic.
I have followed Howard's "stellarjourney" more than a year. Had tested a while Onstep on Mega2560 with Bluetooth but had hesitate to start building controller because did not have a mount. Now I use a dobson mount on the equatorial platform.
But almost a year ago I was lucky enough to buy a pair of 190 mm diameter 359 teeth worm wheels with worms for a very, very good price. So I had no another choice than to build a mount.
So I have had to get more deeply acquainted with mechanics (I am electronic engineer) and have obtained a lot of new skils and knowledge. I have created a drawings and ordered the parts in a local workshop.
And, of course, I needed a controller. So have built the Onstep controller.
And finally, yesterday evening, was the first field test of the mount and controller. Of course it was just a first test and there are a couple of things to improve or finish. But I am happy it works, motors are capable to drive a load (track and slew). For the test I have used the Alpha branch.
Basic elements are:
OTA is Skywatcher 254/1200
Onstep built on MaxPCB v 1.11,
Teensy 3.6,
ESP8266 ( it is Chinese Ebay stuff, so there is some problems uploading firmware through Teensy, so I use upload via USB/serial adaptor),
DS3231
Drivers for RA/DEC Chinese Ebay TMC2130 (had to modify the boards as per Pedro post https://groups.io/g/onstep/message/1877)
Drivers for the Focusers - DRV8825 (have used them at the first tests for RA and DEC on the table).
Motors for RA/DEC are 17HM15-0904S.
Motor PSU - 24V
Gear ratio motor pulley to worm pulley 1,72413793103448 (15 to 26 teeth T2.5 ), worm wheel 359 teeth.
For now I use "'Stellarium" and "Stellarium scope" for navigation.
The Onstep has started to work from the first software upload and power up.
If there was any problem - it was related to the my mistakes in configuration only (at least till now).
It works using PC and Android either as well as ASCOM drivers.
I hope I will enjoy after I will finish it.
















Pedro Fernandes
 

Hi Gintautas,

I'm impressed with this mount diy.

With this mount you will get fantastic guiding accuracy.

I'm also looking for two sets of gears at fair prices, but it's very hard to find.

Congratulations on your courage to develop such a project.

Congratulations to putting this telescope in station with all the rigor that it imposes.

Pedro

Gintautas Drazdauskas
 

Well, 
I have made a try to remove some photos added by accident and it seems the whole post was removed. Or is it redirected to any other place?
Thanks for good words.
Have to fight with excessive backlash. I made a spring loaded warm and it is not very good. Will make fixed probably.

Gintautas

Howard Dutton
 

Gintautas, I pulled a copy of what I think is your original post from Alain's reply and re-posted so it's easy to find...

Hi there,
I am Gintautas from Lithuania.
At first I want to say a lot of thanks and to pay obeisance to the Howard, Khalid and everyone who collaborate creating and developing the Onstep project. It is fantastic.
I have followed Howard's "stellarjourney" more than a year. Had tested a while Onstep on Mega2560 with Bluetooth but had hesitate to start building controller because did not have a mount. Now I use a dobson mount on the equatorial platform.
But almost a year ago I was lucky enough to buy a pair of 190 mm diameter 359 teeth worm wheels with worms for a very, very good price. So I had no another choice than to build a mount.
So I have had to get more deeply acquainted with mechanics (I am electronic engineer) and have obtained a lot of new skils and knowledge. I have created a drawings and ordered the parts in a local workshop.
And, of course, I needed a controller. So have built the Onstep controller.
And finally, yesterday evening, was the first field test of the mount and controller. Of course it was just a first test and there are a couple of things to improve or finish. But I am happy it works, motors are capable to drive a load (track and slew). For the test I have used the Alpha branch.
Basic elements are:
OTA is Skywatcher 254/1200
Onstep built on MaxPCB v 1.11,
Teensy 3.6,
ESP8266 ( it is Chinese Ebay stuff, so there is some problems uploading firmware through Teensy, so I use upload via USB/serial adaptor),
DS3231
Drivers for RA/DEC Chinese Ebay TMC2130 (had to modify the boards as per Pedro post https://groups.io/g/onstep/message/1877)
Drivers for the Focusers - DRV8825 (have used them at the first tests for RA and DEC on the table).
Motors for RA/DEC are 17HM15-0904S.
Motor PSU - 24V
Gear ratio motor pulley to worm pulley 1,72413793103448 (15 to 26 teeth T2.5 ), worm wheel 359 teeth.
For now I use "'Stellarium" and "Stellarium scope" for navigation.
The Onstep has started to work from the first software upload and power up.
If there was any problem - it was related to the my mistakes in configuration only (at least till now).
It works using PC and Android either as well as ASCOM drivers.
I hope I will enjoy after I will finish it.















Pedro Fernandes
 

On Mon, Apr 9, 2018 at 04:31 am, Gintautas Drazdauskas wrote:
Have to fight with excessive backlash.
Has the main wheel and the worm been machined in sequence or not?

Ideally, the two elements have been manufactured with one another forming a selected pair.

It can be a simple matter of adjusting the wheelbase, trying to eliminate the gap as much as possible.

Pedro

Howard Dutton
 

On Mon, Apr 9, 2018 at 06:23 am, Howard Dutton wrote:
The Onstep has started to work from the first software upload and power up.
If there was any problem - it was related to the my mistakes in configuration only (at least till now).
I like to hear things like this once in a while.  :)
Yours is very nice work too.

Gintautas Drazdauskas
 

Thanks a lot Howard.

Gintautas Drazdauskas
 

I do not know they had been machined in sequence or not. I have got everything wrapped in to a bubble packaging film as separate pieces.
It is not a gap problem. I do not know how to explain it in english but it is something like of a pivot construction problem. One side of the worm holder is mounted on the pivot axis, another side is pushed by the spring to the wheel side. And if the wheel is rotated to that spring side (by hand, or when the load balance changes direction) it pushes the worm and worm goes a little bit down. If I apply more tension to the spring then worm would stick. Yesterday I have got a consultation form the real precision mechanical engineer at my home (what a destiny - yesterday we have met very first time at the neighbours picnic). So he assured me to fix the holder at the correct position after I will measure eccentricity of the wheel. I will try.

Khalid Baheyeldin
 

Gintautas,

Your post has been added to the Wiki's showcase page.

JoAnn
 

What a beauty. Would love to know how this compares to a multi thousand dollar mount. I have been thinking about a ,pillow block mount for a while but sourcing nice worm gears is a challenge. Ed Byers has all his last item on eBay for very reasonable but even so its $500-700 each. But then again I have no place for a permanent mount so I'd be looking at just a nice upgrade to my old CG5. 

Matthewabey@...
 
Edited

I converted a 12.5 inch newtonian to an imaging setup on a custom made EQ mount both made by my father in 1991. Its running an old version of onstep and works great. This scope won Stelaphane in 1993 for craftsmanship im hoping to re enter it in the near future with the new drives and Onstep.
 
https://flic.kr/s/aHsmb5JtbY

Currently in progress is my more portable rig completely built from the get to use onstep. Im currently in the process now of programing some arduinos and screens to have control over the polar alignmemt axis's which will allow me to use the pole master to align it without ever getting out of my chair. It is running a Onstep mini with the focusers on a breakout board. It is a few months from completion. 

https://flic.kr/s/aHsm5U2cHe

Matthewabey@...
 
Edited

This is my astrobin for the 12.5 Newtonian. The optics are old Galaxy Optics that are in desperate need of recoating and my imaging skills are not great yet with this size rig. The ota is 80 lbs loaded with 60lbs worth of counter weight all being slewed around by a 400 step nema 17 on a 359t worm drive on RA, a 200 step 5:1 planetary nema17 with a 7.1 byers wormgear on dec with tmc2100 drivers at 24v in stelthchop no loss of steps and respectable slew speeds for the size.

https://www.astrobin.com/users/Matthew_Abey/

Khalid Baheyeldin
 

Good work!

Reminds me of the mid 1980s Meade DS-10 that I used to have ...

Added to the Showcase page on the wiki.

Kenric Ma
 

Hi,

This is my example of converting a Takahashi NJP mount to GOTO using OnStep.

I used the original mounting hardware and gears from the existing PD5XY motor drive system. Reduction ratio is 1:2.66667 for RA and 1:5 for DEC.  

MCU is Arduino Mega 2560 with DRV8825 motor driver and ESP-01. I soldered my own shield and recently added a DS3231 RTC with the help of Howard.

The stepper motors are:  200 step NEMA17 (60mm length) for RA and 200 step NEMA 17 (42mm length) for DEC. I used a DC-DC step up module to run the motors on 24V.

3D printed motor housings, mounting plates and controller case.

Attached are some photos.

Cheers

Kenric Ma
Auckland
New Zealand

Howard Dutton
 

On Wed, Apr 11, 2018 at 12:07 PM, <Matthewabey@...> wrote:
Currently in progress is my more portable rig completely built from the get to use onstep. Im currently in the process now of programing some arduinos and screens to have control over the polar alignmemt axis's which will allow me to use the pole master to align it without ever getting out of my chair. It is running a Onstep mini with the focusers on a breakout board. It is a few months from completion. 

https://flic.kr/s/aHsm5U2cHe
Wow, I can only begin too imagine the time and effort that went into this.