Evolution of prototype 5 in combination with prototype 1.
The V-slot is attached to the wheelchair in stead of the dog's collar.
The little balls at the end of the ropes (zie afb) will be thrown in the V-slot-box by the dog.
Step 1: throw the ball at the end of the leash in the V-slot.
Step 2: put your head through the loop.
Step 3: start walking
Step 1: grab the ball at the end of your collar (hanging next to the head)
Step 2: move or walk; the loop becomes bigger.
Step 3: Remove your head from the loop.
V-slot with box for the ball