I want one of these very badly and lack the skills to make my own and hubby doesn't have the time. Well after a few hours searching the net I think I have found the answer. Its a drapery opener (just the machine not the whole track) from smarthome.com for about 89.00US. Can be set up on timer and distance of draw can be adjusted. Just have to set-up your pull cord like a pull cord for drapes. While still expensive it is a solution. Now I just have to find one in canada.