Abstract: Embodiments of the present disclosure relate to a smart tracking-based projection method and system. The method includes: acquiring information of a real space of a spatial information capturing unit, constructing a 3D model of the real space, and acquiring first position information of a projection picture; acquiring target image information of a target tracking unit, and acquiring second position information of a tracking target based on the target image information; acquiring a target projection region based on the 3D model and the second position information; acquiring, based on the target projection region, rotation information desired by the projection unit; and controlling, based on the rotation information, a drive unit to operate such that the projection picture reaches the target projection region.

Abstract: A ladder having a first box rail having a first side, and a second side extending perpendicularly from the first side. The first side having a first hole. The second side having a first hole in alignment with the first hole of the first side. The ladder having a second box rail, at least a portion of which is in parallel and spaced relation with the first box rail. The ladder comprises a first hollow tube disposed in the first box rail in alignment with the first hole of the first side and the first hole of the third side. The ladder comprises a bracket having a first bracket hole in alignment with the first hole of the first side. The ladder comprises a first fastener extending through the first hole of the third side, the first hollow tube, the first hole of the first side and the first hole of the bracket which attaches the bracket to the first box rail. A method for using a ladder. A method for producing a ladder.

Abstract: A ladder having a first rail having a bottom and a web, a first flange attached to a first end of the web and a second flange attached to a second end of the web. The ladder having a second rail. The ladder having rungs attached to the first rail and second rail upon which a user steps to climb the ladder. The ladder having a foot having a plastic body with a recess which receives the end of the first rail and is positioned about and conforms to the web and the first and second flanges of the first rail. The foot has a plastic base having a top side from which the body extends. The base has an edge positioned about the body with perforations, and a rubber tread disposed along an underside of the base and extending through the perforations and along the edge on the top side of the base to form an overmolded portion of the tread that attaches the tread to the base without any mechanical or other types of fasteners.

Abstract: A ladder having a first rail having a bottom and a web, a first flange attached to a first end of the web and a second flange attached to a second end of the web. The ladder having a second rail. The ladder having rungs attached to the first rail and second rail upon which a user steps to climb the ladder. The ladder having a foot having a plastic body with a recess which receives the end of the first rail and is positioned about and conforms to the web and the first and second flanges of the first rail. The foot has a plastic base having a top side from which the body extends. The base has an edge positioned about the body with perforations, and a rubber tread disposed along a underside of the base and extending through the perforations and along the edge on the top side of the base to form an overmolded portion of the tread that attaches the tread to the base without any mechanical or other types of fasteners.

Abstract: A ladder having a first box rail having a first side, and a second side extending perpendicularly from the first side. The first side having a first hole. The second side having a first hole in alignment with the first hole of the first side. The ladder having a second box rail, at least a portion of which is in parallel and spaced relation with the first box rail. The ladder comprises a first hollow tube disposed in the first box rail in alignment with the first hole of the first side and the first hole of the third side. The ladder comprises a bracket having a first bracket hole in alignment with the first hole of the first side. The ladder comprises a first fastener extending through the first hole of the third side, the first hollow tube, the first hole of the first side and the first hole of the bracket which attaches the bracket to the first box rail. A method for using a ladder. A method for producing a ladder.

Abstract: A ladder having a first rail having a bottom and a web, a first flange attached to a first end of the web and a second flange attached to a second end of the web. The ladder having a second rail. The ladder having rungs attached to the first rail and second rail upon which a user steps to climb the ladder. The ladder having a foot having a plastic body with a recess which receives the end of the first rail and is positioned about and conforms to the web and the first and second flanges of the first rail. The foot has a plastic base having a top side from which the body extends. The base has an edge positioned about the body with perforations, and a rubber tread disposed along a underside of the base and extending through the perforations and along the edge on the top side of the base to form an overmolded portion of the tread that attaches the tread to the base without any mechanical or other types of fasteners.

Abstract: The disclosure relates to a hand-held cleaning device including an elongated nozzle base having opposed first and second ends and a longitudinal axis. The second end is releasably connected to a hand-held suction wand of a vacuum source. The longitudinal axis of the elongated nozzle base is aligned with a longitudinal axis of the wand. A battery is located in the elongated nozzle base. A DC motor is located in the elongated nozzle base and is electrically connected to the battery. The motor has an axially rotated output drive shaft. A drive assembly is connected to the drive shaft for rotation therewith. A first brush is located at the first end of the elongated nozzle base and is connected to the drive assembly.

Abstract: The disclosure relates to a hand-held cleaning device including an elongated nozzle base having opposed first and second ends and a longitudinal axis. The second end is releasably connected to a hand-held suction wand of a vacuum source. The longitudinal axis of the elongated nozzle base is aligned with a longitudinal axis of the wand. A battery is located in the elongated nozzle base. A DC motor is located in the elongated nozzle base and is electrically connected to the battery. The motor has an axially rotated output drive shaft. A drive assembly is connected to the drive shaft for rotation therewith. A first brush is located at the first end of the elongated nozzle base and is connected to the drive assembly.