Abstract: A user can place the multifunctional mobile appliance in a work area bounded by a set of impulse radio, or GPS, transceivers. The appliance independently and accurately maps the work area and proceeds to perform one or more tasks over that area, as directed by the user. These tasks include, but are not limited to, mowing, vacuuming, scrubbing, waxing, and polishing. The user may control, through the World Wide Web, what tasks are performed where and when. Both the user and the appliance can make use of services that are provided on the Internet to enhance the performance of the appliance. The appliance is safe, silent, self-sufficient, nimble, and non-polluting. It is equipped with sensors to enable it to avoid obstacles and other less than optimal operating conditions.

Abstract: A user can place the multifunctional mobile appliance in a work area bounded by a set of impulse radio, or GPS, transceivers. The appliance independently and accurately maps the work area and proceeds to perform one or more tasks over that area, as directed by the user. These tasks include, but are not limited to, mowing, vacuuming, scrubbing, waxing, and polishing. The user may control, through the World Wide Web, what tasks are performed where and when. Both the user and the appliance can make use of services that are provided on the Internet to enhance the performance of the appliance. The appliance is safe, silent, self-sufficient, nimble, and non-polluting. It is equipped with sensors to enable it to avoid obstacles and other less than optimal operating conditions.

Abstract: A device and method to convert light from a point source into an areal source of displayed light. The reflective faces of dielectric mirrors enclose a point source of light. The mirrors repeatedly reflect the light from the point source inside the enclosure without significant absorption, thereby achieving a random distribution of position coordinates for the light rays departing the areal transmissive surface on the outside of the enclosure. The device and method may be used for backlighting a display or for other areal lighting systems.

Abstract: The invention utilizes time domain reflectrometry to obtain a measure of the length of wire connecting an electrical appliance to its power distribution panel. An unauthorized change in this length is interpreted as an attempt to steal the appliance. Coded disabling keys are provided to allow an authorized user to unplug and move the appliance. The invention can be mounted within the appliance, requires no modification of the existing wiring or receptacles and is unaffected by power failures.