Abstract: An apparatus and method for indicating a contour of a surface relative to a vehicle, in which a first electromagnetic radiation source projects a first beam to create a first reflection pattern on the surface. A second electromagnetic radiation source projects a second beam to create a second reflection pattern on the surface. An apparatus is provided for coupling the first and second electromagnetic radiation sources to the vehicle, such that a movement of the vehicle results in a movement of the first and second reflection patterns on the surface.

Abstract: Disclosed is a reticle generator having an azimuth array (64) of light emitting diode filament lines and an elevation array (66) of orthogonal light emitting diode filament lines. The arrays (64, 66) are fixed by rigid bracket members (136, 144) with respect to the faces (74, 80) of a partially reflecting prism (76). An illuminated LED filament line projected into the prism (76) by azimuth array (64) is reflected by the partially reflecting surface (82), and emitted from prism face (84). A selected LED filament (78) from elevation array (66) is transmitted through the prism (76) and emitted from face (84) and thus superimposed with the azimuth filament line (72).

Abstract: A circuit is provided for apparatus of the type in which a member is reciprocated through a work stroke relative to a support on which work is placed and from which it is removed by the operator. Typical operations are cutting and forming. The circuit includes two parallel leads and a pair of switches in control of both leads, one switch for each hand of the operator. The switches are normally closed with reference to the first lead. The second, normally open lead includes a device which, when energized, initiates the work stroke and the first lead includes means enabling the second lead to be closed relative to the device if the operator actuates both switches but the means of the first lead cannot again be operated unless and until both switches are in their normal position.