I needed a bigger faster raking and leaf pickup process, so I built a two axis arm for controlling the 8" diameter hose from the e-tek powered electric vacuum.
The arm is powered by some automotive electric window motors with actuators. One moves the hose out to the right and back, and the other tilts the hose up and down.
The control handle for this motorized hose assembly uses two radioshack DPDT 20A 12V spring return to center heavy duty switches. The one mounted in the handle controls the up and down motor, and the one in the rear section of the control handle is actuated when the handle is rotated out and in around the pivot. The window motors move fast, and by adjusting the attachment points and control arms I was able to get a fast stable control of the hose.
The rake frame took several tries to get right, with the most important aspect being the best rake angle to the ground. Straight down works best, which is equivalent to the rake passing right past your feet while manually raking. The weight of the raking frame is counter balanced by a large garage door spring attached to the control handle. The spring is tensioned with a come along that can be tuned to make the rake frame neutral, and slightly lifted off the ground. To rake, I push the rake frame control handle forward, then I back up the machine. The beauty of this approach is that the rake stroke can be quite long. After one or two passes with the rake to bring the leafs into a pile, the pile of leaf is sucked up with the robotic hose arm.
It works nicely, but I decided to build a large vacuum nozzle that will sit on the rake frame, and suck up the leafs as they are raked, so fewer passes will be required. I got the nozzle built, but the snow stopped my testing, so I will have to wait until spring to further refine the attachment.