Laser projection system and method
A laser projection system for projecting an image on a workpiece includes a photogrammetry assembly and a laser projector, each communicating with a computer. The photogrammetry assembly includes a first camera for scanning the workpiece, and the laser projector projects a laser image to arbitrary locations. Light is conveyed from the direction of the workpiece to the photogrammetry assembly. The photogrammetry assembly signals the coordinates light conveyed toward the photogrammetry assembly to the computer with the computer being programmable for determining a geometric location of the laser image. The computer establishes a geometric correlation between the photogrammetry assembly, the laser projector, and the workpiece for realigning the laser image to a corrected geometric location relative to the workpiece.
1. A method for projecting an image onto a workpiece comprising:
providing a laser projector configured to project a laser image onto the workpiece and an optical sensor assembly for detecting light reflected from the direction of the workpiece;
periodically emitting light toward the workpiece for detection by said optical sensor assembly;
using the optical sensor assembly for optically detecting the location of a plurality of reference targets disposed upon the workpiece by detecting light emitted toward the workpiece that is reflected from the reference targets toward the optical sensor including scanning a space comprising the workpiece establishing a background image and subtracting the background image from light reflected by the plurality of retroreflective targets;
calculating the location of the workpiece within a geometric coordinate system based on the location of the plurality of reference targets;
causing the laser projector to project a template onto a desired geometric location of the workpiece for a manufacturing operation based upon the calculated location of the workpiece;
monitoring for relative movement between the workpiece, the laser projector, and the optical sensor assembly by repeatedly updating the calculation of the workpiece within the geometric coordinate system based upon the location of the plurality of reference targets disposed upon the workpiece as determined by light reflected from the reference targets toward the optical sensor assembly; and
correcting the template being projected onto the workpiece based upon movement of the workpiece.
2. The method set forth in claim 1 further including determining a geometric correlation between the optical sensor assembly and the laser projector.
3. The method set forth in claim 1 wherein the geometric coordinate system is a three-dimensional coordinate system.
4. The method set forth in claim 1 wherein the optical sensor assembly includes a photogrammetry assembly comprising first and second cameras that are spaced apart from each other by a fixed distance.
5. The method set forth in claim 1 wherein the emitted light includes a wavelength of between 520 nm and 540 nm.
6. The method set forth in claim 1 wherein the template is a manufacturing template for performing a weld operation or a machine operation on the workpiece.