AUTOMATED OBJECT DIMENSIONING SYSTEM EMPLOYING CONTOUR TRACING, VERTICE DETECTION, AND FORNER POINT DETECTION AND REDUCTION METHODS ON 2-D RANGE DATA MAPS

• US 20020014533A1
• Filed: 06/07/1999
• Published: 02/07/2002
• Est. Priority Date: 12/18/1995
• Status: Abandoned Application

• Current Assignee: Metrologic Instruments Incorporated (Honeywell International Inc.)
• Original Assignee: Metrologic Instruments Incorporated (Honeywell International Inc.)
• Inventors: BLAKE, ROBERT E., AU, KA MAN, SCOTT, IAN, SCHNEE, MICHAEL, GOOD, TIMOTHY A., KNOWLES, CARL HARRY, KOLIS, GEORGE, ROCKSTEIN, GEORGE B., NAYLOR, CHARLES, GERMAINE, GENNADY, ZHU, XIAXUN, WILZ, DAVID M. Sr., GROOT, JOHN, DICKSON, LEROY
• Application Number:
  US09/327,756
• Publication Number:
  US 20020014533A1
• Time in Patent Office: Days
• US Class Current: 235/472.01
• CPC Class Codes: B82Y 15/00 Nanotechnology for interacting, sensing or actuating, e.g. quantum dots as markers in protein assays or molecular motors
• CPC Class Codes: G01S 17/58 Velocity or trajectory determination systems; Sense-of-movement determination systems
• CPC Class Codes: G01S 17/88 Lidar systems specially adapted for specific applications
• CPC Class Codes: G01S 17/89 for mapping or imaging
• CPC Class Codes: G01S 7/4817 relating to scanning
• CPC Class Codes: G01S 7/4818 using optical fibres
• CPC Class Codes: G02B 26/106 having diffraction gratings as scanning elements, e.g. holographic scanners holographic optical elements G02B5/32, holography G03H
• CPC Class Codes: G06K 17/0022 arrangements or provisious for transferring data to distant stations, e.g. from a sensing device "transfer between computer elements G06F13/00 "; data-transmission H04L
• CPC Class Codes: G06K 2207/1013 Multi-focal
• CPC Class Codes: G06K 7/10 by electromagnetic radiation, e.g. optical sensing; by corpuscular radiation
• CPC Class Codes: G06K 7/10564 Light sources
• CPC Class Codes: G06K 7/10584 Source control
• CPC Class Codes: G06K 7/10594 Beam path
• CPC Class Codes: G06K 7/10603 Basic scanning using moving elements
• CPC Class Codes: G06K 7/10663 using hologram
• CPC Class Codes: G06K 7/10673 Parallel lines
• CPC Class Codes: G06K 7/10693 for omnidirectional scanning
• CPC Class Codes: G06K 7/10702 Particularities of propagating elements, e.g. lenses, mirrors G06K7/10831 takes precedence
• CPC Class Codes: G06K 7/10722 Photodetector array or CCD scanning
• CPC Class Codes: G06K 7/10792 Special measures in relation to the object to be scanned
• CPC Class Codes: G06K 7/10801 : Multidistance reading
• CPC Class Codes: G06K 7/10811 : Focalisation
• CPC Class Codes: G06K 7/10851 : Circuits for pulse shaping, amplifying, eliminating noise signals, checking the function of the sensing device basic electronic circuitry H03
• CPC Class Codes: G06K 7/10861 : sensing of data fields affixed to objects or articles, e.g. coded labels postal sorting B07C3/14, conveying articles B65G47/48
• CPC Class Codes: G06K 7/10871 : randomly oriented data-fields, code-marks therefore, e.g. concentric circles-code
• CPC Class Codes: G06K 7/10881 : constructional details of hand-held scanners
• CPC Class Codes: G06K 7/10891 : the scanner to be worn on a finger or on a wrist
• CPC Class Codes: G06K 7/109 : adaptations to make the hand-held scanner useable as a fixed scanner
• CPC Class Codes: G06K 7/14 : using light without selection of wavelength, e.g. sensing reflected white light G06K7/10831 - G06K7/1097 take precedence
• CPC Class Codes: G07F 9/002 : Vending machines being part of a centrally controlled network of vending machines
• CPC Class Codes: G07G 1/0054 : with control of supplementary check-parameters, e.g. weight or number of articles
• CPC Class Codes: H01L 21/28575 : on semiconductor bodies comprising AIIIBV compounds
• CPC Class Codes: H01L 29/452 : on AIII-BV compounds

Abstract

A fully automated package identification and measuring system, in which an omni-directional holographic scanning tunnel is used to read bar codes on packages entering the tunnel, while a package dimensioning subsystem is used to capture information about the package prior to entry into the tunnel. Mathematical models are created on a real-time basis for the geometry of the package and the position of the laser scanning beam used to read the bar code symbol thereon. The mathematical models are analyzed to determine if collected and queued package identification data is spatially and/or temporally correlated with package measurement data using vector-based ray-tracing methods, homogeneous transformations, and object-oriented decision logic so as to enable simultaneous tracking of multiple packages being transported through the scanning tunnel.

Claims

1. An automated package identification and measuring system, wherein an omni-directional laser scanning tunnel is used to read bar codes on packages entering the tunnel, while a package dimensioning subsystem is used to capture information about the package prior to entry into the tunnel.

2. An automatead package identification and measuring system, wherein LAser Detecting And Ranging (LADAR-based) scanning methods are used to capture two-dimensional range data maps of the space above a conveyor belt structure, and two-dimensional image contour tracing methods are used to extract package dimension data therefrom.

3. An automated package identification and measuring system, wherein the package dimensioning subsysten is realized as a LADAR-based package imaging and dimensioning unit (i.e. subsystem) supported above the conveyor belt structure of the system.

4. An automated package identification and measuring system, wherein the LADAR-based imaging and dimensioning subsystem produces a sychronized amplitude-modulated laser beam that is automatically scanned across the width of the conveyor belt structure and, during each scan thereacross, detects and processes the reflected laser beam in order to capture a row of raw range (and optionally reflection-intensity) information that is referenced with respect to a polar-type coordinate system symbolically-embedded within the LASAR-based imaging and dimensioning subsystem.

5. An automated package identification and measuring subsystem, wherein the rows of range data captured by the LADAR-based imaging and dimensioning subsystem are continously loaded into a preprocessing data buffer, one row at a time, and processed in real-time using window-type convolution kernals that smooth and edge-detect the raw range data and thus improve its quality for subsequent dimension data extraction operations.

6. A automated package identification and measuring subsystem, wherein the LADAR-based imaging and dimensioning subsystem automatically substracts detected background information (including noise) from the continously updated range data map as to accommodate for changing environmental conditions and enable high system performance independent of background lighting conditions.

7. An automated package identification and measuring subsystem, wherein the LADAR-based imaging and dimensioning subsystem automatically buffers consecutively captured rows of smoothed/edge-detected range data to provide a range data map of the space above the conveyor belt, and employs two-dimensional image contour tracing techniques to detect image contours within the buffered range data map, indicative of packages being transported through the laser scanning tunnel system.

8. An automated package identification and measuring subsystem, wherein the LADAR-based imaging and dimensioning subsystem automatically processes the indices (m,n) of the computed contours in order to detect vertices associated with polygonal-shaped objects extracted from the range data map, which are representative of packages or like objects being transported through the laser scanning tunnel system.

9. Another object of the present invention is to provide such an automated package identification and measuring subsystem, wherein the LADAR-based imaging and dimensioning subsystem automatically processes the m and n indices of the detected vertices associated with the computed contours in order to detect candidates for corner points associated with the corners of a particular package being transported through the laser scanning tunnel system.

10. An automated package identification and measuring subsystem, wherein the LADAR-based imaging and dimensioning subsystem automatically processes the m and n indices of detected corner point candidates in order to reduce those corner point candidates down to those most likely to be the corners of a regular-shaped polygonal object (e.g. six sided box).

11. An automated package identification and measuring subsystem, wherein the LADAR-based imaging and dimensioning subsystem automatically processes the m and n indices of the corner points extracted from the range data map in order to compute the surface area of the package representated by the contours traced therein.

12. An automated package identification and measuring subsystem, wherein the LADAR-based imaging and dimensioning subsystem automatically processes the m and n indices of the corner points extracted from the range data map in order to compute the x, y and z coordinates corresponding to the corners of the package representated by the contours traced therein, referenced relative to a Cartestion-type global coordinate reference system symbolically embedded within the automated package identification and measuring subsystem.

13. An automated package identification and measuring subsystem, wherein the LADAR-based imaging and dimensioning subsystem automatically processes the m and n indices of the corner points extracted from the range data map in order to compute the average height of the package representated by the contours traced therein, referenced relative to the Cartestion-type global coordinate reference system.

14. An automated package identification and measuring subsystem, wherein the LADAR-based imaging and dimensioning subsystem employs a polygonal-type laser scanning mechanism for scanning an amplitude-modulated laser beam across the width of the conveyor belt.

15. An automated package identification and measuring subsystem, wherein the LADAR-based imaging and dimensioning subsystem employs a holographic-type laser scanning mechanism for scanning an amplitude-modulated laser beam across the width of the conveyor belt.

16. A LADAR-based package imaging and dimensioning subsystem for imaging and/or profiling packages transported thereby a substantially constant velocity.

17. A LADAR-based imaging and dimensioning subsystem, wherein a sychronized amplitude-modulated laser beam is automatically produced and scanned across the width of a conveyor belt structure and, during each scan thereacross, detects and processes the reflected laser beam in order to capture a row of raw range (and optionally reflection-intensity) information that is referenced with respect to a polar-type coordinate system symbolically-embedded within the LASAR-based imaging an d dimensioning subsystem.

18. A LADAR-based imaging and dimensioning subsystem, wherein captured rows of range data are continously loaded into a preprocessing data buffer, one row at a time, and processed in real-time using window-type convolution kernals that smooth and edge-detect the raw range data and thus improve its quality for subsequent dimension data extraction operations.

19. A LADAR-based imaging and dimensioning subsystem, wherein detected background information (including noise) is automatically substracted from consecutively captured rows of smoothed/edge-detected range data to provide a range data map of the space above the conveyor belt, for use in carrying out package dimension data extraction operations involving the same.

20. A LADAR-based imaging and dimensioning subsystem, wherein two-dimensional image contour tracing techniques are used to detect image contours within the buffered range data map, indicative of packages being transported thereby.

21. A LADAR-based imaging and dimensioning subsystem automatically processes the indices (m,n) of the computed contours in order to detect possible vertices associated with polygonal-shaped objects extracted from the range data map, which are representative of packages or like objects being transported by the subsystem.

22. A LADAR-based imaging and dimensioning subsystem, wherein the m and n indices of the vertices associated with the computed contours are automatically processed in order to detect candidates for corner points associated with the corners of packages transported by the subsystem.

23. A LADAR-based imaging and dimensioning subsystem, wherein the m and n indices of detected corner point candidates are automatically processed in order to reduce those corner point candidates down to those most likely to be the corners of a regular-shaped polygonal object (e.g. six sided box).

24. A LADAR-based imaging and dimensioning subsystem, wherein the m and n indices of the corner points extracted from the range data map are automatically processed in order to compute the surface area of the package representated by the contours traced therein.

25. A LADAR-based imaging and dimensioning subsystem, wherein the m and n indices of the corner points extracted from the range data map are automatically processed in order to compute the x, y and z coordinates corresponding to the corners of the package representated by the contours traced therein, referenced relative to a Cartestion-type global coordinate reference system symbolically embedded within the automated package identification and measuring subsystem.

26. A LADAR-based imaging and dimensioning subsystem, wherein the m and n indices of the corner points extracted from the range data map are automatically processed in order to compute the average height of the package representated by the contours traced therein, referenced relative to the Cartestion-type global coordinate reference system.

27. A LADAR-based imaging and dimensioning subsystem, wherein a polygonal-type laser scanning mechanism is used to scan an amplitude-modulated laser beam across the width of the conveyor belt.

28. A LADAR-based imaging and dimensioning subsystem, wherein a holographic-type laser scanning mechanism is used to scan an amplitude-modulated laser beam across the width of the conveyor belt.