Starting Development of new Timelapse Software

Sebastian · **Joined:** Sun Apr 24, 2011 3:08 pm **Posts:** 13

Hello, this is my first post here, though I started a similar thread on the timescapes forums: http://timescapes.org/phpBB3/viewtopic.php?f=43&t=4373

I want to create a new software to control the motion of my Orion/Merlin/Skywatcher with the specific needs of recording motion controlled time-lapse.

I know there is the timelapse preset generator for papywizard but I feel its cumbersome and limiting so I started writing my own application.

What I already have:
A cross platform Java application with the class to send serial commands to my head. I can rotate all axes at any speed.
There is some excellent documentation about the serial protocol here: http://www.papywizard.org/wiki/DevelopGuide#MerlinOrionprotocol though I found some incomplete parts like the speed ratio with the "G" command.

I am also not quite sure yet which value corresponds to which speed as in the command sequence:

L<axis>
G<axis>3<dir>
I<axis>220000
J<axis>

The "3" is the speed ratio and can actually also be 1 for slow and 4 for slew and the "I<axis>220000" (as found out with trial and error) command can take any value between 100000 and FF0000.
4 for slew had some inconsistent behaviour and with no combination of values I was able to get the head to turn as slow as with the handcontrol in guide mode...

What I want to achieve:
Allow full custom curve movements on both axis with a nice GUI to draw curves, preview motion, etc.

The plan is to release everything as open source (GNU GPL V3).

Any help with coding or more details about the serial protocol would be greatly appreciated.

fma38 · **Posted:** Sun Apr 24, 2011 8:10 pm

Claude, I can't find anymore the pdf document about the Merlin protocole someone from a astronomic forum wrote... Do you remember it? This doc can help Sebastian, I think...

claudevh · **Posted:** Sun Apr 24, 2011 10:29 pm

Hello Fréderic and Sebastian ...
I have send the documents I have at disposal by direct mail.

fma38 · **Posted:** Mon Apr 25, 2011 8:24 am

Thanks!

gloob · **Posted:** Mon Apr 25, 2011 8:29 am

Could someone also send me this file. Would be very nice

ozbigben · **Posted:** Mon Apr 25, 2011 8:45 am

Are people using great circle routes for timelapse panning with a change in pitch or just interpolating yaw and pitch?

http://williams.best.vwh.net/avform.htm#Intermediate

claudevh · **Posted:** Mon Apr 25, 2011 11:18 am

To "gloob" Stefan,

I have send the docs to you by Email...

To "All"

I believe that all of you have interest in sharing a maximum of informations about Timelapse.
Please make your code availlable somewhere in the spirit of "open source".
Fréderic have show THE EXEMPLE with Papywizard.

I will say that more then 40 % of the "Papywizard" users are also interested in Timelapse, but the informations are so scatered.

To Frederic, is that not time to create a "dedicated part" for Timelapse into the Papywizard area ?
What do-you thinck about ?

fma38 · **Posted:** Tue Apr 26, 2011 6:46 am

Yes, a sub-forum for timelapse could be nice. But we need to ask Kolor to create it.

AlexandreJ · **Posted:** Tue Apr 26, 2011 9:55 am

Just ask, it's easy to create

claudevh · **Posted:** Tue Apr 26, 2011 6:26 pm

Hello Alexandre,

Could you create a "subforum" for "Timelapse and related applications" & "Timelapse et applications associées" after PANOGEAR in both the English and in the French part.

We will move and reorganise all subjects related to Timelapse into those new parts ...

Many thanks in advance

AlexandreJ · **Posted:** Wed Apr 27, 2011 7:54 am

Done. I've put you and fma38 moderator on these new parts.

claudevh · **Posted:** Wed Apr 27, 2011 10:44 am

Bonjour Alexandre,

J'aurais plutôt vu ce "sous-forum" au même niveau que :

- Motorized panohead project: Merlin, Orion & Papywizard
- Panogear
- Timelapse and related applications <<<<<<<<<<<<<<<<<<<<<<<<<<<<

Et non comme sous forum de Panogear ...
Idem dans la partie française !

Est-ce possible ?

Merci d'avance.

AlexandreJ · **Posted:** Wed Apr 27, 2011 12:18 pm

Bien sure. C'est fait.

claudevh · **Posted:** Wed Apr 27, 2011 2:50 pm

OK Alexandre !
PARFAIT ....

Sebastian · **Joined:** Sun Apr 24, 2011 3:08 pm **Posts:** 13

Here is my first progress report and what I found out so far:

If you see an error or misinterpretation please let me know.

Speed
For continuous movement there seem to be only 2 speed modes/ratios available each with 255 speed settings.

"Slow" goes from 2.16 degrees per minute to 28.08 degrees per minute

"Fast" goes from 56 degrees per minute to 245 degrees per minute

The "Slew" Mode is only good for the GOTO commands which I did not get into yet.

There also seems to be an even slower "track/guide" mode which is available on the handcrontrol but I did not find out yet how to use this mode from the serial interface

Motion
If you just want continous motion with a constant custom speed you can start the motion from the software and then disconnect the cable (and turn off your computer). The head will not stop movement when you unplug the cable.

This is what the program currently looks like:

claudevh · **Posted:** Sun May 01, 2011 10:10 am

Hey Sebastien,

This is taken "live" ....

Could we have a chance to try by ourselve?
What platform do-you use to run your program ?

Normally the Merlin has several speeds:

Slew speeds:
Rate 0 = 1.0X sideral rate (0.25 ° / minute) = Tracking mode sideral !)
Rate 1 = 2X
Rate 2 = 16X
Rate 3 = 32X
Rate 4 = 50X
Rate 5 = 200X
Rate 6 = 400X
Rate 7 = 600X
Rate 8 = 800X Max for Merlin Generation I (Firmware commencing "01.##.##)
Rate 9 = 1000X Max for Merlin Generation II (Firmware commencing "02.##.##)

In fact they are "3 tracking rates" :
Sidereal (default)
Lunar
Solar

Sebastian · **Joined:** Sun Apr 24, 2011 3:08 pm **Posts:** 13

claudevh wrote:

Hey Sebastien,

This is taken "live" ....

Could we have a chance to try by ourselve?
What platform do-you use to run your program ?

Normally the Merlin has several speeds:

Slew speeds:
Rate 0 = 1.0X sideral rate (0.25 ° / minute) = Tracking mode sideral !)
Rate 1 = 2X
Rate 2 = 16X
Rate 3 = 32X
Rate 4 = 50X
Rate 5 = 200X
Rate 6 = 400X
Rate 7 = 600X
Rate 8 = 800X Max for Merlin Generation I (Firmware commencing "01.##.##)
Rate 9 = 1000X Max for Merlin Generation II (Firmware commencing "02.##.##)

In fact they are "3 tracking rates" :
Sidereal (default)
Lunar
Solar

This is Java so its cross platform compatible. It requires the RXTX library (http://rxtx.qbang.org/wiki/index.php/Main_Page) which runs on Windows, Linux, Mac OSX and Solaris.

I plan to finish cleaning up the code and adding more basic functionality to release source and binaries at the end of May.

Do you have any information how to interface these tracking modes with serial commands?

Sebastian · **Joined:** Sun Apr 24, 2011 3:08 pm **Posts:** 13

New Version with integrated GOTO features is ready.

The good news is that the integrated GOTO controller seems to be pretty accurate. Average stepping error is around 0.01°. More accuracy could be achieved by moving the head "manually" with the speed commands and constantly checking the step position and adjusting speed accordingly. With this approach it would take longer to reach the GOTO position but we might be able to get the error down even further.

This does not say much about the real physical motion error due to mechanical components of the head, this is purely about the motion of the motor as measured by the optical encoder.

I looked for a good name for the software before registring for a google code repository and settled for "Chronomotion", I hope you like the name, I dont think Google offers the option to change it...

http://code.google.com/p/chronomotion/

Initial code release is there already, though in still pretty rough condition (like hardcoded "COM1" as port, etc.) and the GPL headers are still missing.

I will deal with cleaning up soon.

fma38 · **Posted:** Wed May 11, 2011 8:03 pm

Looks promising

claudevh · **Posted:** Mon May 16, 2011 11:34 am

Hello Sebastian,

This look very promising indeed.

A few questions ...

I have installed the application on my PC (Java installation, compilation etc ...)
I get the application on my screen but how can I connect ?

I have seen in your code that "COM1" is hard coded, thats OK ... I have changed to COM port of my BT device no problem but I don't get any connection ...

How do you have connected the Merlin head to your PC, wired (TTL 5V convertor like the FTDI) or not wired like the "PapyMerlin" Bluetooth ???

Can-you explain ?

Thank-you for your work !!!

hsestes00 · **Posted:** Sat Jun 11, 2011 4:58 am

So I looked out on the Google site http://code.google.com/p/chronomotion/, but did not see where I could grab a copy to demo with. Is it still available?

claudevh · **Posted:** Sat Jun 11, 2011 9:35 am

Yes this is still at the same place but your URL is faulty ... (a "," too much at the end !)
http://code.google.com/p/chronomotion/

You should be a member of Google (subscribe to a Google account, this is free)

The the best way is to follow the instructions on the Wiki ... and install a "SVN" to recuperate the "fresh" code easylly ...

You can also simply browse the source code ...

There is no "download"yet ...

Have fun and let know your impression !

Sebastian · **Joined:** Sun Apr 24, 2011 3:08 pm **Posts:** 13

I just made the first binary release: http://code.google.com/p/chronomotion/downloads/list

Usage Instructions are here: http://code.google.com/p/chronomotion/wiki/Usage_Instructions

Please note that it is still a very early alpha release and you might discover bugs/problems.

Please test and help with reports about issues here: http://code.google.com/p/chronomotion/issues/list

claudevh wrote:

I have seen in your code that "COM1" is hard coded, thats OK ... I have changed to COM port of my BT device no problem but I don't get any connection ...
How do you have connected the Merlin head to your PC, wired (TTL 5V convertor like the FTDI) or not wired like the "PapyMerlin" Bluetooth ???

I now added auto COM port discovery, so it should automatically list all detected COM ports. If the bluetooth adapter also creates a virtual COM port it should also be listed just like the hardwired ones.

claudevh · **Posted:** Sun Jul 31, 2011 11:03 pm

Hello Sebastian,

I have tested the binary for Windows ... and it work !!!

No problem till now !
The "wired connection" via a "USB to TTL convertor" is OK.
A "Virtual Serial" connection via BT can't be used at this moment.

I have some difficulties with how to use it all ...
A small description of the functionalities will be welcome.

Anyway "GOOG JOB" !!!

Sebastian · **Joined:** Sun Apr 24, 2011 3:08 pm **Posts:** 13

Thanks for testing, great that it works in general!

I do not have a BT setup with the Merlin head but If you can help me understand how to talk to the BT device I will try to integrate it.

So far the software is just a kind of preview. You can rotate the head, start motion in all directions with different speed settings and issue single GOTO commands.

I am now working on more timelapse oriented features. But my philosophy is "release early"

Starting Development of new Timelapse Software

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