Abstract: A robotic cleaning device and method of control thereof. The device and method enable multiple cleaning passes within an environment efficiently, cleaning the entire environment more than once, or cleaning the entire environment and then focusing on one or more particularly dirty areas to provide enhanced cleaning by making one or more passes over a dirty area in a dominant and a non-dominant direction. The robotic cleaning device may identify such areas in the course of its cleaning, or it may record such areas previously as being historically dirty and requiring additional attention. The device may vacuum; it may shampoo; it may polish; or it may perform other cleaning operations. Where the device is battery-powered, the device may check its state of charge before performing the enhanced cleaning, and may repeat the enhanced cleaning if the battery or batteries have sufficient charge.

Abstract: A guitar slide for permitting the user to contact a single string, or any pair of adjacent strings of a stringed instrument. The guitar slide includes a body of a length sufficient to contact any pair of adjacent strings on a stringed instrument, an inner end formed with a hole for receiving the tip of the user's finger, and an outer end formed with an arcuate end cap adapted to be positioned adjacent the tip of the user's finger. The guitar slide body is shorter than the distance between the tip of the user's finger and the first knuckle of the user's finger to assure that the finger has the same flexibility as if the user was not wearing the guitar slide, which length is sufficient to allow guitar slide 1 to contact any two adjacent strings.