A banking system machine is controlled responsive to data read from data bearing records. The docking unit is configured to communicate with a controller of the medical device when the medical device is mounted on the docking unit to instruct the controller to execute a selected program. The first and second differentiators are arranged to double differentiate the impulse to produce a monocycle. The determined energy field characteristics then are used to activate field generators to generate the desired energy field. The openings are made such that excrement cannot pass through openings but the cat litter grit will remain on the base of the cat litter tray.