I was in Europe last year and saw a similar rig, except the peddles were on the handlebars. It mounted to a standard wheel chair by the rider without getting out of his chair. Mounting took about 3 seconds as he snapped it into place and he peddled off with a friend on a regular bike. I didn't get a manufacturer's name, but it was a really neat idea. I do have a picture. He had undone the front to enter a store and then just reattached and rode off...