Gina's Observatory Roll-Off-Roof Automation - Work in Progress

[Gina]

Posted by: @MarkAR

Posted by: @Gina

something to limit the movement to 90 degrees ie. horizontal,

How about a couple of large L-brackets bolted outside to stop and support the weight.

Yes, Just what I was thinking of.  Or at least for the end that isn't supported by the rope.

 

[Gina]

It is pretty much working now.  The end drop-down window is controlled fine from the roof by rope and pulleys but can be disconnected if I want the window open with the roof closed.

I used it "in anger" the other night and found a couple of problems.  The limit switches were not working properly and the current limit for the motor was too high.  The result was that the OPEN limit switch didn't operate and the roof opened as far as it would go and the over-current trip stopped the motor instead.  The result was that the roof was hard against the middle wall framework in the open position with such force that I couldn't free the clutch.  Normally, I would be able to close the roof on the motor as the CLOSED switch would not have been operated but that one was stuck in the other way and the system thought the roof was closed!!  So the interlock stopped the motor operating.  Talk about "Catch 22" !!!  Eventually I freed the CLOSED limit switch and closed the roof on the motor.

As a result of the above, several actions need to be taken :-

1.  The motor was allowed so much torque that it jammed the release clutch provided for the very purpose of allowing manual roof operation regardless of the motor and its control.  So the current limit must be reduced.

2.  The manual motor buttons should be able to run the motor in spite of the limit switches.  Interlock is not required as the buttons are on the control box in the observatory and I can see where the roof is - I don't need to be told by the limit switches.

3.  The operation of both limit switches need looking at!

[Gina]

Reasonable weather today so decided to work on the ROR Control.  Replaced the ESP32 having set the motor current limit lower - it now cuts out at about 4A and that is low enough to allow the clutch to be disengaged and the roof moved manually.  (I tested it with the limit switch disabled.)  Running the roof normally the current never goes above 3A and is getting less as the roof is used and the binding on the north side is getting less with use. 

As per the code change the motor can now be run from the control box irrespective of the limit switches but only runs while the button is pressed.  In normal use the buttons set the flags and the roof continues in motion until stopped by limit switch (or fault detected) or the emergency STOP button is pressed.  The latter clears the flags and the motor stops.

I worked on the operation of the limit switches too and they are now working fine. Also adjusted the fold-down window linkage and got that working fine. As I said, the binding somewhere on the north side is getting less and less as the roof is opened and closed. Just remains now to tidy up, refit plywood wall panels and fit the control box back on the wall.