ASCOM Driver for the Roll-off Roof: It's Live!

Building an ASCOM Driver for My Roll-Off Roof: A VB.NET Adventure!

After deciding to switch from my usual observatory control software to MaximDL 5 + ACP 5 for automation, I knew I’d need to implement several hardware and software modifications at the observatory. On that note, a huge thank you to Robert Denny from DC3 Dreams and Diffraction Limited for generously providing me with licenses for both of these powerful tools and for their support in my automation projects.

My short-term goal is to fully automate the observatory, especially with the hope of one day capturing transient astronomical events like gamma-ray bursts or supernovae. To achieve this, I needed to set up a compatible and cohesive system. The ASCOM platform is perfect for this, allowing developers to create their own drivers for all sorts of astro equipment – domes, cameras, filter wheels, focusers, rotators, mounts… you name it! So, I dove headfirst into creating my very first ASCOM driver… for my roll-off roof!

Now, ASCOM doesn’t directly support “roll-off roofs,” only “domes.” But hey, a roll-off roof can totally be seen as a dome that doesn’t rotate and just happens to have a really, really big slit, right? After a few hours of tinkering, I finally managed to create my first ASCOM driver in VB.NET! Success!

The driver interfaces with a Velleman K8055 experimentation board, which I’d previously used for various tests before fully transitioning to an all-IP setup with an IP Power module. Here’s the K8055 managing the roof control:

Relay board on the reverse:

This driver lets me open and close the roof, and it reports its status: open, closed, opening, or closing (all thanks to my position sensors). Crucially, it also verifies the mount’s parked status before allowing any open or close commands (using my IR sensors). I’m happy to report the driver passed all ASCOM conformity tests, and my initial trials in MaximDL have been more than satisfactory!

Since ACP is, in theory, capable of checking the weather via my AAG Cloudwatcher in ASCOM mode, the roof will be fully automated as soon as everything is installed and properly configured. I’m looking forward to running the full automation tests in a few days, once the skies clear up!

UPDATE 13/2015: I’m now using an IPX800V3 for controlling both the observatory and the roof.