Abstract: A robotic cleaner includes a housing, a suction conduit with an opening, and a leading roller mounted in front of a brush roll. An inter-roller air passageway may be defined between the leading roller and the brush roll wherein the lower portion of the leading roller is exposed to a flow path to the suction conduit and an upper portion of the leading roller is outside of the flow path. Optionally, a combing unit includes a plurality of combing protrusions extending into the leading roller and having leading edges not aligned with a center of the leading roller. Optionally, a sealing strip is located along a rear side of the opening and along a portion of left and right sides of the opening. The underside may define side edge vacuum passageways extending from the sides of the housing partially between the leading roller and the sealing strip towards the opening.

Abstract: An anodizing system uses both positive and negative current pulses. Such pulses are adjustable to achieve different adjusted values of positive and negative currents. These values are sensed and used to maintain automatically such values. The ratio of negative current to positive current is preferably greater than 3% for the production of relatively thick, dyeable, hard anodized coatings and conventional (normal) anodic coatings of light shades of integral colors using a simple sulfuric acid bath which may be maintained at relatively high temperatures. Current may be applied at nearly full current density initially without burning. In some cases, additional means may be provided to increase the throwing power by eliminating the negative current and using means such as capacitors or inductors to prolong the decay of the positive pulses, preferably such that the then composite positive pulses are maintained above a zero value.