How to automate my Exploradome

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KathyNS Canada
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Re: How to automate my Exploradome

#21

Post by KathyNS »


In order to ensure that the home position is accurate, the controller rotates off home and then back onto home before operating the shutter. So if you are simulating the home switch for breadboarding, you need to close the switch (off home) and then re-open it (on home) before the shutter will move.
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DSO AP: Orion 200mm f/4 Newtonian Astrograph; ATIK 383L+; EFW2 filter wheel; Astrodon Ha,Oiii,LRGB filters; KWIQ/QHY5 guide scope; Planetary AP: Celestron C-11; ZWO ASI120MC; Portable: Celestron C-8 on HEQ5 pro; C-90 on wedge; 20x80 binos; Etc: Canon 350D; Various EPs, etc. Obs: 8' Exploradome; iOptron CEM60 (pier); Helena Observatory (H2O) Astrobin
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Re: How to automate my Exploradome

#22

Post by Nitram »


Thank you very much for your reply,

I have a some questions for you.
I dont want to find some errors, I just want to be sure my understanding is ok about Arduino coding.
I am not an expert.

1-In your Arduino pinout TXT,
-for pin A2, the description is (active low = left) for manual shutter.
For the shutter is not supposed to be Open or Close ?
-for pin A1 and A5 the decription is A1(analog in) and A5 Analog read.
Not sure but I think Thermistor as a DS18B20 and DT22 are working with digital pins ?

2-In your arduino sketch you have this line (const int TrigerHomePin = 20;)
Can you explain me what that line do ?

3- I want to ask you the permission to modify the code?
We need some Addon, and I will used a arduino Mega
My brother have wind sensor with speed and wind direction
Need 2 extra pins to read this sensor 1 digital and 1 analog
I will call your (rain detect pin 11) as (weather safety) and trigger that pin 11 for rain, wind gusting at certain amount and if the wind came from specific direction.
I will need a extra digital pin for reading the RG11 rain sensor.

Thanks again,Appreciate your help.
Martin
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KathyNS Canada
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Re: How to automate my Exploradome

#23

Post by KathyNS »


Nitram wrote: Sun Dec 12, 2021 10:17 am 1-In your Arduino pinout TXT,
-for pin A2, the description is (active low = left) for manual shutter.
For the shutter is not supposed to be Open or Close ?
That is a cut-and-paste error. It should read (active low = close)
-for pin A1 and A5 the decription is A1(analog in) and A5 Analog read.
Not sure but I think Thermistor as a DS18B20 and DT22 are working with digital pins ?
Pins A0-A5 can be used as analog or digital. The only one that is used as analog is A1: thermistor in. All the others are read as digital.
There is no support for DS18B20 device. The thermistor is just a temperature-sensitive resistor. The input measures voltage across the thermistor.
The DT22 is a digital device, and its pin is used in digital mode.
2-In your arduino sketch you have this line (const int TrigerHomePin = 20;)
Can you explain me what that line do ?
No, I can't explain it. The current version of the sketch does not use it, and I do not recall what, if anything, it did. The actual home sensor is on pin 8.
3- I want to ask you the permission to modify the code?
We need some Addon, and I will used a arduino Mega
My brother have wind sensor with speed and wind direction
Need 2 extra pins to read this sensor 1 digital and 1 analog
I will call your (rain detect pin 11) as (weather safety) and trigger that pin 11 for rain, wind gusting at certain amount and if the wind came from specific direction.
I will need a extra digital pin for reading the RG11 rain sensor.
It was never my intention to release this code publicly, and I do not actively support it. Which means that it is up to you to make it work for your installation. If you credit me as the original author, that is great, but you will have to make it yours in order to make it work and to maintain it. Do whatever you need to do.
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DSO AP: Orion 200mm f/4 Newtonian Astrograph; ATIK 383L+; EFW2 filter wheel; Astrodon Ha,Oiii,LRGB filters; KWIQ/QHY5 guide scope; Planetary AP: Celestron C-11; ZWO ASI120MC; Portable: Celestron C-8 on HEQ5 pro; C-90 on wedge; 20x80 binos; Etc: Canon 350D; Various EPs, etc. Obs: 8' Exploradome; iOptron CEM60 (pier); Helena Observatory (H2O) Astrobin
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Re: How to automate my Exploradome

#24

Post by cbweb »


cbweb wrote: Sat Nov 13, 2021 10:51 am Hi Kathyns,

I've made some progress purchasing required Stepper/Driver and Arduino, following tutorials online I can send basic commands to the Stepper from Arduino Uno plus I'm beginning to formulate a plan for the track aspect moving the dome. I've moved on to examine the Walkerdome Arduino code. Initially, I'd like to be able to drive the Dome in azimuth only at this time no need for shutter control. Also in Walkerdome Arduino code there is included temp/humidity/rain code with an additional Arduino library to support this. My question is, what is the simplest way to Azimuth drive the dome? Should I comment out all reference to additional library code eg code that reads weather conditions from DHT and shutter control? More importantly, is there a schematic diagram that can lay out the connections that need to be made in Arduino plus its connections to the driver and its pins. I'm using a 480g/gm² with a Cloudray 3DM308S driver and Arduino Uno. Just begun to learn Arduino...Any help appreciated thanks.








Thanks for pic and heads up re possible mismatch between Exploradome kit.

Re..
Here is an old photo of the original rotation motor, the drive pinion and ring gear, and the aluminum dome rings. The lower ring is fixed, and the upper ring rotates and supports the dome.

... acquiring the aluminum dome rings aspect I'll focus on for Pulsar use Or alternative approach. That aspect needs sorting before I proceed further.

Thanks,

Colm
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Re: How to automate my Exploradome

#25

Post by Nitram »


Hello Kathy,
Thanks for your last reply.
I just start back to the dome project to be ready for install it at spring.

Just let you know I will not modify your code. I will putt a second Arduino for the wind speed and other weather sensor.

I have other questions for you about manual operation.
Have you made some test with the manual control ?
Is it work at any time ? in any circumstance ?
What do Manual stop button ? It just stop where it is ? or it stop the session, slew the dome at home and close the shutter ?
Do you know somebody who can help me to make an Ascom driver for the second Arduino, it will handle a Weather station ?

Thanks again for your help.
Martin
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Re: How to automate my Exploradome

#26

Post by Nitram »


Hello Kathy,
Just to let you know I have found the text where you explain how the manual operation is working.
Everythings is working now for the manual operation.
The only thing is when I open SG Pro and connect WalkerDome I get a Shutter error, but I soon I open or close the shutter the error disapear.
Is it normal to get this error in the beginning in SG Pro ?

Regards
Martin
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Re: How to automate my Exploradome

#27

Post by KathyNS »


Hi, Martin. Sorry I missed your Feb 25th post. Glad you got it working.

The shutter error occurs because the Arduino does not know what position the shutter is in when it is first turned on. This is normal.

In my dome, I leave my computer on 24/7 (it handles my weather station, too), so the Arduino is always powered from the USB port. As a result, it remembers the (typically) closed state from the previous session. If I have had the power off for any reason, mine too comes on with a shutter error. The error is easily cleared by manually checking where the shutter is (typically closed) and issuing a command to send it to that position.

The reason for this is that the "shutter movement completed" signal is a momentary one. It is active only while the shutter is receiving power. Once the shutter reaches the open or closed position, the limit switches divert the motor power to the "completed" signal. As soon as the Arduino receives that signal, it shuts off motor power for safety reasons, and the completed signal disappears.

I thought about having the Arduino send power to the shutter motors on startup to initialize its position information. But it would have to pick a direction: open or closed. If it guessed right, nothing would happen besides the brief home position confirmation movement of the dome. However, if the shutter happened to be open and it gave a Close signal, it would result in an uncommanded shutter movement. I decided that that was unsafe. I would rather have it occasionally give an error.

If I see a shutter position error, I just turn on the interior lights and look with the webcam to verify the actual shutter position.
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DSO AP: Orion 200mm f/4 Newtonian Astrograph; ATIK 383L+; EFW2 filter wheel; Astrodon Ha,Oiii,LRGB filters; KWIQ/QHY5 guide scope; Planetary AP: Celestron C-11; ZWO ASI120MC; Portable: Celestron C-8 on HEQ5 pro; C-90 on wedge; 20x80 binos; Etc: Canon 350D; Various EPs, etc. Obs: 8' Exploradome; iOptron CEM60 (pier); Helena Observatory (H2O) Astrobin
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Re: How to automate my Exploradome

#28

Post by KathyNS »


Nitram wrote: Fri Feb 25, 2022 2:23 pm Do you know somebody who can help me to make an Ascom driver for the second Arduino, it will handle a Weather station ?
You should download the ASCOM Developer Package from the ASCOM site. It is the only approved way to develop a driver. The kit includes driver templates for all ASCOM device types. For a weather station, you would want to make either an Observing Conditions driver or a Safety Monitor driver. The templates are available for C# and VB.Net.

The driver template handles driver registration, and includes everything the driver needs to do to communicate with ASCOM-compatible software. All you have to do is tell it how to operate the hardware when it receives a particular command.
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DSO AP: Orion 200mm f/4 Newtonian Astrograph; ATIK 383L+; EFW2 filter wheel; Astrodon Ha,Oiii,LRGB filters; KWIQ/QHY5 guide scope; Planetary AP: Celestron C-11; ZWO ASI120MC; Portable: Celestron C-8 on HEQ5 pro; C-90 on wedge; 20x80 binos; Etc: Canon 350D; Various EPs, etc. Obs: 8' Exploradome; iOptron CEM60 (pier); Helena Observatory (H2O) Astrobin
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Re: How to automate my Exploradome

#29

Post by Nitram »


Hello Kathy,
Thanks again for the explanation and your help.
I just seen your post on Cloudynights about the RG-11 rain sensor. It's exactly the one we have puschased for our the project.
Can you tell me if you have test some other dip switch settings, to avoid false positive with the dew ?

Here is a picture of the work in progress :)
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Re: How to automate my Exploradome

#30

Post by KathyNS »


Nitram wrote: Sun Mar 06, 2022 3:46 pm Hello Kathy,
Thanks again for the explanation and your help.
I just seen your post on Cloudynights about the RG-11 rain sensor. It's exactly the one we have puschased for our the project.
Can you tell me if you have test some other dip switch settings, to avoid false positive with the dew ?

Here is a picture of the work in progress :)
Image
I am using the second-lowest setting. The dip switch settings are (order 7..1): 0 0 1 x x 0 1. That is listed as "Mode 1 - It's Raining" / "Sensitive - Turn on with very light rainfall." I found that the "Very Sensitive - First detected raindrop" setting was too sensitive and triggered on heavy dew.
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DSO AP: Orion 200mm f/4 Newtonian Astrograph; ATIK 383L+; EFW2 filter wheel; Astrodon Ha,Oiii,LRGB filters; KWIQ/QHY5 guide scope; Planetary AP: Celestron C-11; ZWO ASI120MC; Portable: Celestron C-8 on HEQ5 pro; C-90 on wedge; 20x80 binos; Etc: Canon 350D; Various EPs, etc. Obs: 8' Exploradome; iOptron CEM60 (pier); Helena Observatory (H2O) Astrobin
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Re: How to automate my Exploradome

#31

Post by Nitram »


I will try your settings.
Do you know if it decect snowfall ?
I have seen some schematic where they put a 100 ohms resistor in series between the signal from the sensor and the Arduino pin, have you that 100 ohms resistor ?
I already know I dont need the 10K pullup, because you are using the internal pullup resistor of the Arduino.

Regards
Martin
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Re: How to automate my Exploradome

#32

Post by KathyNS »


Nitram wrote: Sun Mar 06, 2022 7:14 pm I will try your settings.
Do you know if it decect snowfall ?
I have seen some schematic where they put a 100 ohms resistor in series between the signal from the sensor and the Arduino pin, have you that 100 ohms resistor ?
I already know I dont need the 10K pullup, because you are using the internal pullup resistor of the Arduino.

Regards
Martin
I am not sure about snowfall. Typically, if it is snowing, I am not interested in using the dome, so I tend not to monitor the sensor. I suspect it would depend on several variables: the moisture content of the snow, the temperature, whether the RG-11's dew heater is working.

I can't comment on the schematic with the resistor without seeing it. Maybe they are doing the external pull-up with a voltage that is incompatible with the Arduino? A series resistor would protect the Arduino's input.

I don't use any external resistor. The relay in the RG-11 is a simple pull-down contact, bringing the Arduino's input down to ground level when it is activated. There is no need for a series resistor in my application, and as you noted, I use the internal pull-up resistor.
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DSO AP: Orion 200mm f/4 Newtonian Astrograph; ATIK 383L+; EFW2 filter wheel; Astrodon Ha,Oiii,LRGB filters; KWIQ/QHY5 guide scope; Planetary AP: Celestron C-11; ZWO ASI120MC; Portable: Celestron C-8 on HEQ5 pro; C-90 on wedge; 20x80 binos; Etc: Canon 350D; Various EPs, etc. Obs: 8' Exploradome; iOptron CEM60 (pier); Helena Observatory (H2O) Astrobin
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Re: How to automate my Exploradome

#33

Post by Nitram »


Hello Kathy,
The project going well. I am about 3d print the rotation gear I have design.
I use a 30 to 1 gear ratio between the ring and the motor.
Can you tell if your gear ratio is around that 30 to 1?
Regards
Martin
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Re: How to automate my Exploradome

#34

Post by KathyNS »


Nitram wrote: Fri Mar 25, 2022 11:25 am Hello Kathy,
The project going well. I am about 3d print the rotation gear I have design.
I use a 30 to 1 gear ratio between the ring and the motor.
Can you tell if your gear ratio is around that 30 to 1?
Regards
Martin
The drive ratio of my rotation system from the pinion to the ring is 177/14, or 12.6 to 1.
Image
DSO AP: Orion 200mm f/4 Newtonian Astrograph; ATIK 383L+; EFW2 filter wheel; Astrodon Ha,Oiii,LRGB filters; KWIQ/QHY5 guide scope; Planetary AP: Celestron C-11; ZWO ASI120MC; Portable: Celestron C-8 on HEQ5 pro; C-90 on wedge; 20x80 binos; Etc: Canon 350D; Various EPs, etc. Obs: 8' Exploradome; iOptron CEM60 (pier); Helena Observatory (H2O) Astrobin
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Re: How to automate my Exploradome

#35

Post by SparWeb »


Hi,
I've been following this thread with interest, though I don't have a dome myself.

Earlier I noted that the plastic ring gear of an Exploradome was to be avoided if possible, and an aluminum ring gear was preferred.
That made sense then, but now I see mention of a 3D printed gear.

Do you have any photos (or CAD screen capture) of the design you're working on?
How have you resolved the wear and fragility issues of plastic parts?
Sounds like a really interesting approach to the problem which is why I'm curious.
Steven Fahey
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Re: How to automate my Exploradome

#36

Post by Bert »


G'day Kathy

I am in the process of automating my Sirius Dome and have started to explore the WalkerDome and DomeSync systems developed by you. I've downloaded WalkerDome ASCOM Driver V1, WalkerDome Arduino Code V2 and DomeSync V3. I am still at the breadboard stage of configuration and testing. I think that the problem that I am getting is maybe related to my configuration/setup but I am not sure. I can connect to my ASCOM telescope driver and the WalkerDome Ascom driver and DomeSync shows the telescope's Azimuth and calculates the Azimuth position for the dome close to where the telescope is pointing.

However, I can't get any reponse to move the stepper motor. What I have noticed in the log file is that there is a conversion from string to double error that is repeatedly generated by the system (see below):

2022-10-08 19:06:09 SendCmd: P0
2022-10-08 19:06:09 reply:K
2022-10-08 19:07:53 SendCmd: I
2022-10-08 19:07:53 reply:WD Arduino v2.0
2022-10-08 19:07:53 SendCmd: D0
2022-10-08 19:07:53 reply:K
2022-10-08 19:07:53 SendCmd: P1
2022-10-08 19:07:53 SendCmd: C2300
2022-10-08 19:07:53 SendCmd: Q
2022-10-08 19:07:53 reply:C2300E497H1R0A127D+L0S0
2022-10-08 19:07:53 Conversion from string "C2300E497H1R0A127D+L0S0" to type 'Double' is not valid.
2022-10-08 19:07:55 Conversion from string "C2300E497H1R0A127D+L0S0" to type 'Double' is not valid.
2022-10-08 19:07:57 Conversion from string "C2300E497H1R0A127D+L0S0" to type 'Double' is not valid.
2022-10-08 19:08:01 Conversion from string "C2300E497H1R0A127D+L0S0" to type 'Double' is not valid.
2022-10-08 19:08:06 Conversion from string "C2300E497H1R0A127D+L0S0" to type 'Double' is not valid.
2022-10-08 19:08:10 Conversion from string "C2300E497H1R0A127D+L0S0" to type 'Double' is not valid.
2022-10-08 19:08:14 Conversion from string "C2300E497H1R0A127D+L0S0" to type 'Double' is not valid.
2022-10-08 19:08:17 Conversion from string "C2300E497H1R0A127D+L0S0" to type 'Double' is not valid.
2022-10-08 19:08:20 Conversion from string "C2300E497H1R0A127D+L0S0" to type 'Double' is not valid.
2022-10-08 19:08:20 GotoAz: 187 from: 199.878260869565 steps: 82
2022-10-08 19:08:20 SendCmd: L82
2022-10-08 19:08:20 reply:K
2022-10-08 19:08:23 SendCmd: Q
2022-10-08 19:08:23 reply:C2300E394H1R0A45D-L0S0
2022-10-08 19:08:23 Conversion from string "C2300E394H1R0A45D-L0S0" to type 'Double' is not valid.


The above is not a full extract of the log file (the last line is repeated many times). I suspect that the conversion problem occurs when the steps needs to be generated to slew the dome and that is maybe why I am not getting any output to move the stepper motor but I am just taking a wild guess.

Could you please advise what the possible cause of this behaviour may be?

Many thanks
Bert Kruger
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Re: How to automate my Exploradome

#37

Post by KathyNS »


Thanks for the log extract.

The error message seems to be generated on the response to the Query command, which occurs every 2 seconds. The string it is trying to convert is the query response, which is a pretty weird thing to do. It looks vaguely familiar, so it might be something that I fixed a while back. I am working on another bug fix at the moment, but when I am done, I will make sure I upload the most current version of everything.

The calculation of the number if steps is correct, based on the numbers I am seeing. You have calibrated 2300 steps per revolution, which is 6.39 steps per degree. The requested slew of -12.88 degrees is indeed a left slew of 82 steps, which is what was requested. So the driver is correctly translating degrees to steps.

The Arduino thinks it did the slew correctly. It went from a local azimuth (relative to your Home position) of 127 to 45, which is a left slew of 82 steps, as instructed.

I don't think the conversion error is related to the failure to slew. The slew problem might be in the connections to the stepper driver if the motor is not even trying to move.

Is the motor trying to move at all? I wonder, because of the low number of steps per degree. I don't know how the weight of your dome compares to mine, but 6 steps per degree is going to take a huge amount of torque and a monster motor.

Unless you have changed the step timing in the Arduino code, it is going to try to do that 12 degree slew in a tiny fraction of a second. (The default timing is to step the motor at 2 kHz, after a 1-second acceleration period. In this case, the slew would be all acceleration and deceleration, so it would never get up to 2kHz.) That kind of acceleration is pretty much impossible. If it is even trying to move at that rate, you would simply hear a click, because the time frame is so short. I would not expect any actual movement.

You need much more reduction gearing. Or your calibration is incorrect. If your motor could run at that speed, your settings would give a dome rotation rate of one full 360-degree rotation in 1.15 seconds. It would make an effective fan at that speed! (For reference, my setup is calibrated at 135791 steps per revolution, which is 377 steps per degree.)
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DSO AP: Orion 200mm f/4 Newtonian Astrograph; ATIK 383L+; EFW2 filter wheel; Astrodon Ha,Oiii,LRGB filters; KWIQ/QHY5 guide scope; Planetary AP: Celestron C-11; ZWO ASI120MC; Portable: Celestron C-8 on HEQ5 pro; C-90 on wedge; 20x80 binos; Etc: Canon 350D; Various EPs, etc. Obs: 8' Exploradome; iOptron CEM60 (pier); Helena Observatory (H2O) Astrobin
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Re: How to automate my Exploradome

#38

Post by KathyNS »


To assist in a rough calibration, multiply:
- number of microsteps per motor full step (if microstepping; otherwise use 1)
- number of motor steps per motor revolution
- motor gearbox ratio
- gear ratio of any external gearbox
- dome drive ratio

As an example, here is my calculation:
2 microsteps per motor full step (I half-step the motor)
200 full steps per motor rev
26.85 motor gearbox ratio
1 (no external gearbox)
12.64 dome drive ratio (177 teeth on dome ring / 14 teeth on drive pinion)
2 * 200 * 26.85 * 12.64 = 135790.55 (Discrepancy due to rounding of multiplied numbers.)

So my calibration is 135791 steps per rotation.
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DSO AP: Orion 200mm f/4 Newtonian Astrograph; ATIK 383L+; EFW2 filter wheel; Astrodon Ha,Oiii,LRGB filters; KWIQ/QHY5 guide scope; Planetary AP: Celestron C-11; ZWO ASI120MC; Portable: Celestron C-8 on HEQ5 pro; C-90 on wedge; 20x80 binos; Etc: Canon 350D; Various EPs, etc. Obs: 8' Exploradome; iOptron CEM60 (pier); Helena Observatory (H2O) Astrobin
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Re: How to automate my Exploradome

#39

Post by Bert »


Thanks for the replies.

I've made a mistake with the circumference specified as 2300 (not sure where the figure came frame) whereas the value should have been the number of steps required to complete one rotation.

However, I still don't get any response to the stepper motor. The following persistent error is given from the ASCOM driver (copied from the log file):

-------------------
2022-10-11 06:39:50 Dome tracking enabled
2022-10-11 06:39:52 Dome slewing to 188.9
2022-10-11 06:39:52 Dome failed to Slew: ASCOM.WalkerDome.Dome.
CheckDotNetExceptions ASCOM.WalkerDome.Dome SlewToAzimuth System.Exception: Unable to slew with an invalid azimuth. Typically, trying to slew while already slewing. (See Inner Exception for details)
2022-10-11 06:39:52 Error moving dome: CheckDotNetExceptions ASCOM.WalkerDome.Dome CommandString System.Exception: Command ISPWRFAIL was not understood. (See Inner Exception for details)
2022-10-11 06:39:53 Dome stopped slewing
2022-10-11 06:39:53 Error moving dome: CheckDotNetExceptions ASCOM.WalkerDome.Dome CommandString System.Exception: Command ISPWRFAIL was not understood. (See Inner Exception for details)
2022-10-11 06:39:56 Dome slewing to 188.9
2022-10-11 06:39:56 Error moving dome: CheckDotNetExceptions ASCOM.WalkerDome.Dome CommandString System.Exception: Command ISPWRFAIL was not understood. (See Inner Exception for details)
2022-10-11 06:39:57 Dome stopped slewing
2022-10-11 06:39:57 Error moving dome: CheckDotNetExceptions ASCOM.WalkerDome.Dome CommandString System.Exception: Command ISPWRFAIL was not understood. (See Inner Exception for details)
2022-10-11 06:40:00 Dome slewing to 188.9

etc.
-----------------
The above is repeated many times and I think the error prevents the slew from being initiated.

I am also not sure if it has something to do with the following line in the Aurduino code that is trying to write seriral output to the ASCOM software about the Rainstatus and/or Power Fail Status?

Serial.print(RainStatus + 2 * PwrFailStatus);

I will wait for an update of the software before trying it again unless you can guide me something else that I can change or try in the meantime.
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JeffBevan United States of America
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Re: How to automate my Exploradome

#40

Post by JeffBevan »


I have gone down this path as well. My dome is entirely home built and as such my dome rings are plastic (lexan) easily purchased as 4'x8' sheets here in the US for a reasonable price. The dome a 10' dia. one which weighs about 175 lbs rolls very easily, as I recall 35-40 lbs of force. As far as the ASCOM driver is concerned I am going down the rabbit hole with LesveDome. Seems pretty straight forward so far. I am fairly resourceful so that helps.
Home built dome, 12" Meade LX 200 OTA, cem 60 ec, sbig stf 8300c, Starshoot AutoGuider Pro, Orion Off-axis
patience!
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