A method and apparatus for optically determining the dimension of part surfaces. Particular embodiments describe optical triangulation based coordinate measurement machines capable of accurate measurement of complex surfaces, such as gear teeth and turbine blades. Other embodiments provide highly useful sensors for robot guidance and related purposes. Up to 5 axis sensing capability is provided on surfaces of widely varying form.

Method and apparatus for electro-optically determining the dimension, location and attitude of objects including light spot centroid determination

A system for mapping terrain from an overhead position such as from an aircraft by scanning an array of terrain segments to measure at least two polarization parameters of the light reflected therefrom, together possibly with other parameters to represent spectral components of the reflected light, thereby to derive digital indications thereof for parameter measurement matrices corresponding to each measured parameter. A computer is used to perform a matrix operation to derive at least one additional matrix representing an interrelationship between the measured parameters. The additional matrix is used to derive a map-type display of the terrain in terms of the interrelationship of polarimetric values.

Computerized polarimetric terrain mapping system

A device is disclosed which enables calculation of the location of an object within a three dimensional work area. The system utilizes a pair of position sensing detectors each of which is surrounded by light emitting diodes (LED's) and requires attachment of a retro-reflector to each target whose position is to be determined. In a preferred embodiment, each position sensing detector is surrounded by infrared LED's of two different light wavelengths. Two targets are present in the work area each with a retro-reflector attached thereto and each including a single bandpass filter, in front of its retro-reflector, one target having a bandpass filter corresponding to one LED wavelength and the other target having a bandpass filter corresponding to the other LED wavelength. Circuitry is also disclosed which drives the LED's and interprets the signals received by the position sensing detectors so that the position of the two targets may be determined and displayed in the form of x, y, and z coordinates.

Passive optical position measurement system

An optical system for tracking a target scans an optical beam across the target in a Lissajous pattern. The pattern has at least one portion that extends across the target. Return signals reflected from the target are used to calculate the range (and, if desired, also the intensity) of each measured point on the target (and beyond the target if some portions of the pattern miss the target), and to calculate the deviation of a reference location on the pattern, e.g. its center, from a selected location of the target. This deviation is used to correct the scan to move the reference location on the pattern towards the selected location on the target, thus tracking the target. The amplitude of the pattern can be changed to adjust the pattern on the target or to search for a target. By virtue of the range data obtainable for points on the target and on edges of the target, the system can also determine other features, such as the shape, profile, identity and attitude of the target.

Optical tracking system

A pattern recognition system wherein an image dissector tube is used to provide a scan of an optical image, which scan, when used to establish the degree of similarity of two patterns or changes occurring in a single pattern, is capable of being modified to produce the maximum information required to establish said similarity or change, such modification being achieved by changing the electronic commands controlling the position and movement of the electronic image of the deflectable photomultiplier such that the size, shape, and position of the scanned area and the size of the effective aperture used to generate the scan is modified by appropriate control circuits (normally used in a feedback mode) to insure that the said modification increases the quantity, accuracy, and processability of the said information, full use being made of all a priori knowledge available to constrain scan size, shape, and position, and effective aperture size to further insure optimum scan parameters to provide the required information in the required form.

Pattern recognition system having electronically controllable aperture shape, scan shape, and scan position

Apparatus for establishing and maintaining a predetermined angular relation to a source of radiant energy

Object locating system using image centroid measurement

Apparatus for plotting contour maps automatically employing a cathode ray tube

Strapdown star tracker for space vehicle attitude control, using scanning and error-signal determination method

Morris M Birnbaum

Papers

Apparatus for establishing and maintaining a predetermined angular relation to a source of radiant energy

Object locating system using image centroid measurement

Apparatus for plotting contour maps automatically employing a cathode ray tube

Strapdown star tracker for space vehicle attitude control.