Tug O Love
The owner is yanked left and right by her dogs. A minimalist mechanism, a double spiral, moves the dogs left and right.
Check out the YouTube video to see it in action. There's a description of how I made it as well as detailed photos below...
I made this for friends who have two English springer spaniel dogs. I got the idea after I saw the dogs yanking our friend in opposite directions.
Firstly, I made a quick and simple prototype. It used a push/pull handle to move the dogs horizontally by 2 inches. It worked rather well.
I wanted the final version to be hand cranked. It took a lot of time, thought and trial and error to design a compact mechanism. The problem was the mechanism became ridiculously tall if I used cams. I wasn't aware of a bell crank at that time, or other tricks, so I ended up designing the double spiral you can see in the above photo. It looks pretty cool though! It's made from 4 discs of 3/4-inch thick Baltic birch plywood, glued together.
Most of the other wood is cherry, although the figures are hand carved from basswood. Brass rods are used for the stylus and dog movement.
My wife painted the figures and took covert photos of our friends and their dogs, so this was a team effort.
Coming soon: detailed photos