Abstract: A robotic welding system has a remote light pattern generator and a remotely located video camera and controller connected to an arc welding torch by flexible coherent fiber optic bundles. The improved torch has integral projection and viewing optical systems supported on the ring-shaped torch body. The first projects the light pattern onto the workpiece to measure workpiece profile and detect the joint location; the second produces an image of the weld puddle and light pattern for use as feedback information. The optical systems are tilted away from one another at a small angle corresponding to the angle of reflection to provide for optimum interception of the projected light pattern by the viewing optics.

Abstract: Structured light patterns are introduced into the arc vicinity within the field of view of the integral optical sensor on a gas tungsten arc welding torch. Processing the image yields data needed to guide the torch and control and assess the weld process. The optical welding torch has a projector system with a remote light source and flexible fiber optic bundle over which the light pattern passes to an exit projection and relay assembly mounted on the torch. A programmable laser pattern projector, useful for other applications, has a beam deflection device that traces a two-dimensional pattern on the entrance of a coherent fiber optic bundle; no moving parts or electrical connections are needed at the terminal end. An optional modulator changes the pattern intensity spatially or temporally.

Abstract: A gas tungsten arc welding torch suitable for robotic welding has an improved built-in optical vision sensor which images the weld puddle and weld region on the face of a fiber optic cable; the image is relayed to a video camera and computer to control the torch motion and weld process. The electric arc is much brighter than the area around the arc it is desired to image. A shaped blocking device on the tungsten electrode, such as a molybdenum sleeve or collet set back so that the arc is undisturbed, prevents the arc from being imaged and eliminates image distortions caused by the presence of the bright arc.

Abstract: A portable, low-cost, bichannel image processing and enhancement system t can be programmed to accept two video sources, operate upon one or both simultaneously and deliver an enhanced result to a color monitor. The operations that can be performed on each source include, for example, unity gain, logarithmic amplification and differentiation, and both outputs thereafter can be subjected to such arithmetic operations as addition, subtraction and multiplication. The results are passed through an electronic user programmed window, color encoded by a quantizer and then displayed on a color monitor. The processor includes an area measurement circuit which quantitatively measures the percentage of the screen covered by any of the levels used in the quantizer, a luminance distribution analyzer which generates an histogram approximation to the distribution of grey levels in the image and a luminance cross-section analyzer which displays a graph of the image luminance along a vertical line.