Gina's Observatory Roll-Off-Roof Automation

[Gina]

Unfortunately, I couldn't understand what the man was saying - the sound wasn't very good.  I'll look up "websockets" on Google.

[Gina]

I'll read through that when my brain is cooler!

[wimvb]

As in your weather station thread, I believe that mqtt can handle this. A weather station and the roof controller are clients. A raspberry pi is the server (broker in mqtt language), which sends data received from one client (the weather station) to another (roof controller), or even several others (+ a display unit?).

Definitely worth looking into, imo.

[Gina]

Yes, that sounds good.

[Gina]

Done some repairs on my observatory.  Fastened some shiplap boards that had come loose, plus other parts.  Fitted the new cover for the large chain wheel and the wheel itself.  Fitted perfectly - amazingly!  I'll take a photo later - recovering from the exertion and heat/humidity ATM.

[Gina]

I may need to rethink the operation of the fold down east window.  I was going to use the rather Heath-Robinson rope and pulley system operating from the roof but I realise that the window often needs separate operation from the roof.  That has been particularly evident in this hot weather when I have wanted the roof closed but the window open.  I could really do with a window that I could open on the west end wall to allow a through airflow but that is a major piece of work!  OTOH we don't get this sort of weather very often.

ATM the rope and pulley system can be reconnected quite easily at any time so I could resurrect that system for the winter.  It's only necessary to close the window if rain or snow is expected from the east.  With the prevailing SW wind the window can be left open if it rains so maybe I don't need to rethink the window operation after all.

[Gina]

On 11/08/2020 at 07:24, wimvb said:

As in your weather station thread, I believe that mqtt can handle this. A weather station and the roof controller are clients. A raspberry pi is the server (broker in mqtt language), which sends data received from one client (the weather station) to another (roof controller), or even several others (+ a display unit?).

Definitely worth looking into, imo.

Do you think this is the simplest way of controlling the roof?  I've also had mention of "web sockets".   Can a "broker" do more than just control traffic?  Like operate a display?  I find it interesting that the broker should be an RPi rather than the main desktop.  Agreed that this would mean the desktop wouldn't need to run for MQTT to operate.

[wimvb]

Clients do the job. In INDI language, clients are as indi-drivers/hardware devices and indi-clients, whereas the broker is like the indi-server. The broker handles communication and message (data) storage. Clients supply the messages (data) and receive the data. Clients then take the appropriate actions. That’s why esp32 (and arduino?) can be clients and a raspberry pi can be broker.

[Gina]

Had a look at MQTT on Google and it looks relatively straightforward.  However, I reckon you or someone else has written basic parts of the code I would need for my weather station and ESP32 devices.  Don't want to "reinvent the wheel" if I can help it.

[wimvb]

7 hours ago, Gina said:

Had a look at MQTT on Google and it looks relatively straightforward.  However, I reckon you or someone else has written basic parts of the code I would need for my weather station and ESP32 devices.  Don't want to "reinvent the wheel" if I can help it.

I’ll do some digging in my code repository tonight.

[wimvb]

I did a test with mqtt, where I used my ESP32 sky quality meter and published that to a Raspberry Pi MQTT broker. These micropython files did the trick. Since the sensors all use i2c, changing the code so that it will work with a weather station shouldn't be too difficult. The randsomnerdstutorials site should provide the necessary information for changing the code to arduino ide/c++. You should also find information there on how to set up mqtt on the RPi.

I used MQTT Explorer on my windows laptop to monitor the messaging to and from the RPi.

boot_git.py

main.py

tsl2591.py

umqttsimple.py

[Gina]

I have pretty much decided to go with MQTT for weather station and obsy roof control (and who knows what else).  I like the modular approach yet encompassing everything.  Seems RPi broker, several ESP32 and ESP8266 clients and client on my Linux Mint box producing graphs and charts.  Could add a wall display client too.

Edited August 12, 2020 by Gina

[Gina]

It's looking like this and weather station thread may spawn a new one for the MQTT system.

[Gina]

 

[Gina]

As posted in the MQTT thread, I'm definitely going to use MQTT to control the roof and have already written some code and designed the controls.  I'm pretty sure I know how to do this.  The only doubt is how well the rain detector will work.  I will be doing some experiments.

[Nigella Bryant]

13 minutes ago, Gina said:

As posted in the MQTT thread, I'm definitely going to use MQTT to control the roof and have already written some code and designed the controls.  I'm pretty sure I know how to do this.  The only doubt is how well the rain detector will work.  I will be doing some experiments.

You're so clever Gina, I'd have no Idea.

[Gina]

I've pretty much decided on the design of the remote control of the ROR and now I'm looking into controlling the fold-down window which I find I need to control separately as there are times when I want the window open and the roof closed.

[Gina]

This is what I had controlling the window from the roof.  But I can only separate window from roof by unhooking the pulley block.

And because the window has no force on it tending to open it I had to produce some as shock cord to a fence post outside - not a very "engineering" solution 😁

I'm thinking a counterbalance weight may be better and a push-pull or rotary window opening/closing arrangement.

[Gina]

Because this happened and it jammed.

I made my own 3D printed block which cured the problem by made it less easy to uncouple.  I guess I could add a hook and get over that problem.  But there's still the silly shock cord method of pulling the window open which I don't really like.

 

[Gina]

I'll have a think as to whether I want full independent remote control of the window, with all the complication that involves in the design, or whether I only want the window open when I'm in the observatory or it's no problem to pop back and forth from the house.

[Gina]

Cord control system for east window.  Window opens and closes with the roof.

[Alan White]

Very nice solution Gina, that Roof sounds wonderful as well.
Hope your OK, not crossed on SGL much of late.

 

[Gina]

I'm fine thank you.

[wimvb]

15 minutes ago, Gina said:

I'm fine thank you.

Nice to see you here, Gina.