Electro-optical gaging system

Abstract

Computerized electro-optical system gages dimension of a moving hot bar. Back-lighted electronic camera head generates high-speed bar shadow pulses which represent the bar dimensions. Bar pulses are processed by way of camera electronics and a digital computer. CRT and printing terminals, interacting with the computer, indicate and/or record cold-size bar diameter measurement, with respect to commercial tolerance references and a gaging system histogram. Camera head electronics includes camera AGC circuit, a digital type one-axis bidirectional linear sweep, bar pulse edge-detection with an autocorrelator to remove noise and enhance the bar pulse, and a digital accumulator of digital bar size signals and digital bar position-in-field-of-view signals. The digital computer assimilates bar size and bar position signals bar temperature, aim size, and other data signals. The computer is programmed to: (a) compensate bar size signal for field-of-view errors and other optical and electronic nonlinearities, bar temperature and other sources of error; (b) calibrate the gage off-line and automatically recalibrate the gage on-line to correct for drift and slope errors; (c) perform a gaging system histogram; and (d) communicate with the CRT and printing terminals and an exterior control system.