Roof Position Status

I've added two magnetic reed switches (of the type used in alarm systems) to the roof and wired them into two digital inputs on the K8055 unit. This has enabled my program to detect whether the roof is closed, fully open, or somewhere in between.

Observatory Automation

For the past few months I've been looking at ways to automate my observatory to make my deep sky imaging more frequent and more convenient, with a view to enabling supernova patrols and automated astrometry/photometry of asteroids.

I can already set up an imaging run but at the moment framing an object in the centre of the FOV and setting up autoguiding is all done manually. Once a night's imaging is complete (or I get too tired!) I park the scope, close the electrically operated roof and turn off power to the mount and the cameras. I tend to split time during imaging between watching progress while in the warm room and then maybe making a brew in the kitchen and watching progress via VNC on the laptop while in the lounge. Staying up all night doesn't make getting to work on time the following day easy! I can't leave it all running and go to bed for fear of the weather changing and it starting to rain all over the kit.

So after looking around on the Internet to see what's possible I decided to begin work on automating my own observatory, having three aims in mind:

1. To be able to leave an imaging run going and go to bed, safe in the knowledge that if it clouds over or starts to rain, the telescope will be automatically parked and the roof closed safely.

2. To be able to set a list of multiple imaging targets that will be automatically imaged during a night - including automatic framing through plate solving and automatic setup of autoguiding per target as required.

3. The final aim - to be able to provide the observatory with a list of imaging targets, which it will work through as weather conditions and hours of darkness permit. The observatory will sense when it is dark and when weather conditions are suitable. Alarms will be able to be set so that if anything "not good" happens then I will be alerted by phone. I will also be alerted when the list of targets has been fulfilled.

After reading various posts on the Internet, especially by http://photonjunkie.com/ I decided to use the Velleman K8055 PC interface module as the link between my observatory hardware and the observatory computer. It has eight digital outputs for driving relays etc, five digital inputs and two analogue inputs. It comes with a dll file which enables programming with various languages including visual basic 6, which I shall use.

First step was to connect the roof controls to the k8055. All I had to do was connect a relay to either side of the switch which I use to manually control opening/closing the roof.

I mounted the relays on veroboard and mounted the board alongside the K8055 in a plastic project box inside the warm room. I used the supplied vb6 demo software to establish that all was working and began writing my own program.

Next step - roof status detection.