Mount Positional Feedback

[Euan]

This is part of a bigger automation project I'm trying to finish before it gets dark again...

I have a very low roof obs that is motorised. At the end of a session I have to park it on it's side to allow the roof to close, but I really don't trust ASCOM or any of the software packages enough to let it do it's thing without some kind of check in place

What I've ended up using is an IR Beam Kit from Maplin

Infrared Beam Kit : TR Kits : Maplin

This uses a sender and receiver both powered by 9V, when the beam between the two is broken is closes a relay. The relay has common, normally open and normal closed contacts

I've mounted both parts in little plastic project boxes. The transmitter is mounted on the scopes, facing the same direction as them. The receiver is mounted where the scopes are pointing when the scope is in it's parked position. It's then wired into a Velleman K8055

The K8055 is connected up the Obs PC. This runs Homeseer for the majority of the automation process, talking back and forth with CCD Commander. When CCDC wants to close the roof, it fires a custom command in Homeseer. Homeseer can then look at the devices listed, and waits for the device "Safety Beam" to change to ON

When this happens, it can then fire a contact closure to close the roof

There is also a reed switch on the roof closure to tell Homeseer that the roof has successfully closed

[SteveL]

One day, when its all built and completed and all the gadgets are blinking away, I would love to come and see this wonder of modern technology at work... if only so I can borrow some ideas for my own (yet to be even planned) obsy

[barkis]

I just marvel at the range of gadgetry that is available to assist in this wonderful activity we are involved in.

Of course it helps a great deal when the user has the knowledge to utilise it all. This latest addition, must give you some peace of mind though Euan.

Ron.

[Merlin66]

Euan,

When you test the set-up, what's the repeatability of the "closed roof" telescope position?

I assume you're using EQdir/ Ascom to set the scope and GOTO....

[Euan]

This latest addition, must give you some peace of mind though Euan.

Oh yes, having a really low roll off roof I don't want to image the carnage that could happen if it hit the mount

[Euan]

When you test the set-up, what's the repeatability of the "closed roof" telescope position?

What do you mean?

I assume you're using EQdir/ Ascom to set the scope and GOTO....

Yeah it's all done via CCDC & EQMOD. I just use the "Park Mount" command in CCDC and it does it's thing. There is a little caveat here though, to set a custom park position (on it's side), I have to use a little script that Chris Shillito gave me. I can post it up later if someone wants it

[Euan]

One day, when its all built and completed and all the gadgets are blinking away, I would love to come and see this wonder of modern technology at work... if only so I can borrow some ideas for my own (yet to be even planned) obsy

Would be happy to show it off! It's great it can fit 0.8 persons in comfortably

...or 1.0 persons slightly bent over sitting on a small fishing stool

[Merlin66]

Euan,

When you ask the scope to goto the roof park position does it always/ 90% of the time/ 70% of the time/ 50% of the time - never? end up in the sensor energise position?

What do you do if you park the scope and the sensor doesn't energise? I assume you have to go out to the observatory and re-set the telescope, then shut the roof? No second chances? ie minimal GOTO then return to the park position to see if it works second time around.

Ken

[Euan]

Euan,

When you ask the scope to goto the roof park position does it always/ 90% of the time/ 70% of the time/ 50% of the time - never? end up in the sensor energise position?

What do you do if you park the scope and the sensor doesn't energise? I assume you have to go out to the observatory and re-set the telescope, then shut the roof? No second chances? ie minimal GOTO then return to the park position to see if it works second time around.

Ken

As long as the mount is keeping it's pointing intact, it works everytime. The only thing that would kill the pointing is a *really* off-target plate solve or killing the power to the mount without parking it first. There is quite a decent margin of error where the sensor will still pick up the transmitter even it's slightly off, but not far enough off to touch the roof.

I would rather not put any second options in just incase it's its closing because it's started raining. As soon as it fails, I get an alert on my laptop in the house. This plays an audio file and also puts on a lamp next to my bed. Using Homeseer means I could have any sort of alarm system set up. At that point it's out of bed and manually close it / park the mount if I have to.

Here is how it fits into the system: http://stargazerslounge.com/imaging-discussion/109227-automated-imaging-finished.html

[gary1968]

Nice one Euan, would love to come over sometime and see this little lot in action. It seems to have evolved a bit since I last saw it

.

Gary

[chrisshillito]

The only thing that would kill the pointing is a *really* off-target plate solve or killing the power to the mount without parking it first.

An off target plate solve shouldn't affect things - EQASCOM's pointing model isn't applied to park (or unpark) positions.

Chris.