An easy Option for Building Arduino ASCOM focuser for non electronics background

[doseri]

Hello

  i would like to make Project for Arduino ASCOM Focuser , but i do not have any background in electronics or arduino , what is the easy Option for building arduion ascom focuser???  a guide to do

  my Arduino Project will by on the Lunt 80 ED & GSO 200MM f/5,any idea how to start up and what do i need to have of list items (Arduino Board type , stepper motor , motor diver ) .

regards

sam

[Mick J]

Hi Sam,

There may be a couple of projects in the DIY pages, this thread runs on a bit but in the end is simple and quite cheap to make :

http://stargazerslounge.com/topic/218975-arduino-ascom-focuser-mark2/

Really starts from post #7,   post #2 shows the part well,   a sourceforge page has lists of parts, sketch etc

Difficult bit is mounting, pulley and belts, or possibly direct.

[Dr_Ju_ju]

I concur, throughout the whole thread there are a couple of similar designs and extensions.  These also show up on source forge e.g. http://sourceforge.net/projects/arduinoascomfocuserpro2diy/?source=directory

[Mick J]

Wow Julian, just downloaded the PDF from your link,  Robert Brown has put some work into that, something to come back to and read later.

[doseri]

the a question now  about the stepper motor ???

my ccd camera , filter wheel and the  TRF-2008 Focal Reducer  the Weight  Almost 1.7kg , any Recommends on the type  and step size to use with the lunt 80mm ed @ f/5.6

[Gina]

I use the 28BYJ-48 which is available in 5v or 12v versions, for my focusers.  Small yet powerful and has built-in 64:1 gearbox.  4096 steps per revolution.  Easily driven from an Arduino and ULN2003AN driver chip.  They are often available with a driver module all ready to connect to Arduino or the ready made modules are available separately.  If you don't want to do much soldering, this is an easy and pretty cheap solution.  A good selection HERE

[sloz1664]

As suggested, download the manual on Robert Browns Sourceforge link. http://sourceforge.n...ource=directory It is very comprehensive and shows various combinations, including component lists. All components can be sourced from Ebay, if you do not want to go to specialist suppliers. I have built two of Robert's auto focusers and I'm very pleased with the finished results.

Steve

[doseri]

I use the 28BYJ-48 which is available in 5v or 12v versions, for my focusers.  Small yet powerful and has built-in 64:1 gearbox.  4096 steps per revolution.  Easily driven from an Arduino and ULN2003AN driver chip.  They are often available with a driver module all ready to connect to Arduino or the ready made modules are available separately.  If you don't want to do much soldering, this is an easy and pretty cheap solution.  A good selection HERE

what wight of the you  camera and  do think the 28BYJ-48 will handle the qhy9m with qhy filter wheel with TRF-2008 wight 

[doseri]

As suggested, download the manual on Robert Browns Sourceforge link. http://sourceforge.n...ource=directory It is very comprehensive and shows various combinations, including component lists. All components can be sourced from Ebay, if you do not want to go to specialist suppliers. I have built two of Robert's auto focusers and I'm very pleased with the finished results.

Steve

 thank you  for the link

i download the Robert Browns manual, in the  it  you need to know what is the Critical Focus Zone for the  telescope ,( what  is CFZ for  lunt 80mm ED) i do not know , the step size for motor what do think to use with lunt 80mm ED)

[Gina]

what wight of the you  camera and  do think the 28BYJ-48 will handle the qhy9m with qhy filter wheel with TRF-2008 wight 

 One of my camera/FW assemblies weighs well over a kilogram - these are powerful little stepper motors.  You may want some additional speed reduction to get fine focussing - I generally use the 10:1 fine focus know with timing belt drive.

[doseri]

 One of my camera/FW assemblies weighs well over a kilogram - these are powerful little stepper motors.  You may want some additional speed reduction to get fine focussing - I generally use the 10:1 fine focus know with timing belt drive.

what about  the Critical Focus Zone ,  any  more info on that  wit focuses ????

[Gina]

I've found the step size well adequate - in fact I use about 5 steps of the stepper motor moves the focus a barely discernable amount so no problem

[sloz1664]

Try this formula from Wilmslow Astro:-

http://www.wilmslowastro.com/software/formulae.htm#CFZ

Steve

[dokeeffe]

I used one of these stepper boards to build an arduino focuser.

http://www.dx.com/p/tb6560-3a-single-axis-controller-stepper-motor-driver-board-green-black-red-217142#.Vm35hhqLSAw

I dont have an ascom driver but if you want to copy any of the code for arduino I've put it here  https://github.com/dokeeffe/ip-focuser

The focuser provides an HTTP api so it should be easy to write an ascom driver.