20 inch ComputerizedTelescope by Mel BartelsAround 1990 I began to build computer controlled telescopes with single upper rings. Here's the first iteration of my 20 inch. This proved quite popular, winning a merit award at RTMC, leading to giving away the software and selling kits.
I experimented in the early 1990's with a mounting design that I called the one armed bandit. One side of the altitude bearings is a single bearing with the other side being the traditional Dob bearing arrangement with two points. But I found the increased vibration at the eyepiece uncomfortable.
This led to the next iteration where I returned to a four point bearing design for the altitude. Richard Berry used his cookbook CCD camera with my scope during the 1995 Oregon Star Party. I also won a Merit Award at 1995 RTMC.
After a couple of years, I gave up the trailer for a ultralight design that would fit into the back of my new small pickup.