Alex Calder invented the "mobile" (see link). He did tons of other fantastic work, but his name has become synonymous with this particular type of hanging structure.
Understanding this is the first part of coming to terms with the principle behind the Alexander Calder Diversity Dog Walker.
Instead of the oddly curved pieces of metal, that hang from a typical Calder mobile, there are harnesses of varying sizes, each of which is intended to control a differently sized dog. Careful balancing and training ensures that if all the varying dogs pull together, the arrangement spreads out and conforms to its intended shape. It's not a very practical apparatus, but then that's not its real intention, though it does function as a walker.
It's true purpose is to allow the walker of multiple dogs to do so as a sort of moving art form, whilst simultaneously paying homage to the great and wonderful Alex Calder.-- xenzag, Feb 13 2010 Alex Calder http://e2-productio...eenshots/calder.jpglike this only with dogs (they can each wear a coloured coat to reinforce the image) [xenzag, Feb 13 2010] Horse Hot Walker http://www.hotwalke...orse_hot_walker.jpgLess to tangle. [jurist, Feb 13 2010] This mobile might work best if it was designed more like an equestrian "hot walker" with the rigs independently supported to revolve around a central fixed pole. <link> (Edit: The independent arms do not have to move in unison, and they could revolve in opposition to one another and at varied diameters, depending on the dog's whim.)-- jurist, Feb 13 2010 This would cause chaos, mayhem and entanglement.
[+]-- wagster, Feb 13 2010 Yes I can see that too if the walker has numerous small dogs. The leash would need only be connected to the central pivot, and the dogs would be inclined to run in circles, each chasing the next, as the action of one directly corresponds to the action of the other. It could shorten the distance the human would have to walk overall, as for each diameter of the circle walked, the dogs would have gone the circumference.-- rcarty, Feb 13 2010 random, halfbakery