Abstract: A system and method of welding or additive manufacturing is provided where at least two welding electrodes are provided to and passed through a two separate orifices on a single contact tip and a welding waveform is provided to the electrodes through the contact tip to weld simultaneously with both electrodes, where a bridge droplet is formed between the electrodes and then transferred to the puddle.

Abstract: A laser diode collimating and aberration correction (LDCC) molded plastic optical system having a refractive lens(es) to collimate fast axis and a refractive lens(es) to collimate the slow axis of the laser diode (this lens combination is termed a cross cylindrical lens system) with a diffractive element(s) to correct for astigmatism and provide circularization of the output laser beam. All optical elements are molded in plastic to high tolerances with regard to the surface optical figure (shape of the curved surface), surface roughness, and alignment between surfaces (tilt, rotation, and translation). With proper alignment of the optical system to a suitable laser diode emitter, the combination of optic and laser diode is capable of delivering diffraction limited performance—collimated beam, circular beam cross section, and no astigmatism.

Abstract: Ultrasonic surface examination, of interest in a variety of manufacturing and maintenance situations, is facilitated by a method which involves localized sensing of a surface wave by optical-fiber interferometry. The method is particularly applicable for examination of surfaces in confined spaces and wherever line-of-sight examination is difficult.