570 likes | 583 Views
Welcome to. Machine Vision Solutions for Part Identification & Traceability. OCR/OCV. 2D Data Matrix. Part Identification. Linear Barcode. Agenda. Agenda Con’t. Agenda Con’t. Part Identification & Traceability Overview Dr. Michael Schreiber DVT Director of Applied Engineering.
E N D
Welcome to Machine Vision SolutionsforPart Identification& Traceability OCR/OCV 2D Data Matrix Part Identification Linear Barcode
Part Identification & Traceability OverviewDr. Michael Schreiber DVT Director of Applied Engineering
Topic Outline • Identification and Traceability • Methods of Identification • OCR • 2D DataMatrix • Marking Methods • Readability
Identification • The ability to recognize a part by unique key features and/or markings • Feature Identification • OCR • 1D Barcodes • 2D Codes
Feature Identification • Size • Shape • Color • Unique Features
Feature Identification • May be able to use existing features • Less Specific • Usually go/no go • Not unique • Less data for traceability
Traceability • Ability to store pertain data • Specific to part, date, lot • Data is Valuable • Inventory control, forecasting, business operation • Recall information • Error Proofing – Making sure part are made in the correct order
Methods of Reading • AlphaNumeric • Ease for Human to read • Takes up a large amount of room • Hardest for Machines to read • 1D Codes • Simple readers • No Error Correction • Large Footprint
Methods of Reading • 1D Stacked Codes • More information, • 2D Codes • Small Footprint • Error Correction Build-In • More information
Industrial OCR • What is Industrial OCR? • Reading of characters in any manufacturing or production environment • Lot Codes, Date Codes, Part Numbers • Typically use OCR “friendly” fonts • OCR A, OCR B, Semi • Undecorated, non-serif fonts • Almost always upper case
Industrial OCR • Semi-conductor • Wafer ID’s • Virgin & in-process • IC part numbers • Laser etched • Fixture ID’s • IC pack numbers
Industrial OCR • Automotive • Metal parts • Engine block, cases, stamped body parts, etc. • Glass • Displays • Aerospace • Similar to automotive
Industrial OCR • General Manufacturing • Metal parts • Pin stamped • Engraved • Warehousing • Labels • Ink-jet, dot matrix • “Junk mail” sorting
Industrial OCR • Pharmaceutical • OCR combined with OCV • Date, lot code inspection & sorting • Stringent FDA standards • Label printers • OCR and/or OCV • High speed
Industrial OCR • Cellular Phone • “Read” displays • Check for missing segments • Medical manufacturing • Many, many more …..
OCR Technologies • Correlation • Mathematical, oldest, slow, clean images only • Geometric • Pattern matching algorithms • Algorithmic • Pre-trained, only perfect character printing • Feature extraction • OCR specific, fast, flexible, trainable
OCR – Feature Extraction • Foreign Languages • Curved Printing • Vertical Printing • Dot Matrix • Handles more Variability
OCR Font Choices • OCR enhanced - best • Serif or decorated fonts - worst • Stroke - best • Segmented – problem for most readers, not DVT • Dot Matrix – big problem for most, not DVT
Typically Tough Font Situations • Non-stroke characters • Imperfect stroke characters • Warped and italicized characters • Dot matrix in this class impossible for most • Touching characters • Varying size and aspect ratio • “Junk” above and/or below characters • Imperfect lighting
Achieving OCR Success • Dot matrix or Stroke fonts • Must be OCR “friendly” • Can be thresholded • Not embedded in patterns or pictures • No gross imperfections running through the text • REPEATABLE IMAGES!!!!!!!!!! • Tougher images can be read, but require more effort
Application Overview • OCR Smart Sensor is trainable • Variety of automatic threshold options • OCR specific filters • Dot matrix or stroke characters • Pre-trained standard fonts • Control of spacing and bounding boxes
1D Codes • RSS-14 • Code 93 • POSTNET • Micro PDF417 • RSS • Limited, Composite, Expanded • Planet Code • UPC Composite • UPC/EAN • Interleaved 2 of 5 • USS-128 • USS-39 • Codabar • PharmaCode • BC412 • PDF417
2D Data Matrix • More Data • 6 to 3116 digits • Smaller Footprint • Reed-Solomon error correction • Up to 50% code degradation • More Tolerance to lighting and marking changes • Many formats: • Square and rectangular • ECC 00, 050, 080,100,140, 200 • ECC-200 preferred on new applications
2D Code Selection • Industry Specific • DataMatrix Prevalent • Automotive Industry Action Group (AIAG) • Department of Defense • Aerospace (IAQG) • NASA • Electronics Industry Association (EIA) • ECC200 for non-specified standard
Less Sensitive to Variability • Skew • Lighting • Size
Marking Factors • Life Expectancy • Material to be printed on • Surface characteristics • Volume • Symbol Size • Space
Marking Methods • Laser Marking • Laser burns surface • Good speed and quality • Semicon, electronics, packaging, medical • Dot Peening • Mechnical stylus dented surface to create dots • Automotive, Aerospace • Ink Jet Printing • Ink leaves colors mark on surface • Surface characteristics determine permanence • High Speed, moving parts, good contrast • Thermal Transfer • Etching (Electro-Chemical ) • Oxidation of metal surface • Round parts
Mark Placement • Flat Surface • Clean Area • Raised surface instead of embedded • Readily visible
Readability/Print Grading • Quiet Zone • Area around Code • Finder Bars • L Shaped used for finding symbol • “Clocking” Pattern • Alternating dots opposite Finder Bars • Data Cells • Encoded Information
Cells • Marking Method determines cell shape and size • Minimum size may be determined by surface texture
Verification/Grading • AIM Standard – A-F Grading • Symbol Decode • Contrast • Print Growth • Axial Non-Uniformity • Unused Error Correction • Other Parameters • Dot Size • Dot Offset
Reading Challenges • Poor Focus • Washed Out • Low Contrast • Non Uniform Background
DVT DMReader • DataMatrix/Readers
Solutions • Intelligent Scanners • OCR, 1D, 2D Reading • DMReader frontend for simple setup • Regular Speed and High Speed • SmartImage Sensors • Color, Higher Resolution, Stainless Steel Options
100 DataMatrix reads per second Stainless steel enclosure that is suitable for FDA-regulated wash-down environment IP66,IP67, and IP68 Rated Industrial I/O and Ethernet connectors Legend 550 Speed Hardware Specs: 640 X 480 Grey- scale resolution Hatachi SH4 Processor 32 Mb RAM 8 Mb Flash 4 to 8 times faster than the Legend 540
CFR 21 Part 11 • Pertains to • Electronic record keeping • Electronic signatures • In Terms of OnLine inspection Systems • Documenting a trail of changes and • Who made the changes
CFR 21 Part 11 • Two DVT Component allow a system to be configured for FDA compliancy. • Access Control • DVT SmartLogger Service
CFR 21 Part 11 • Access Control and SmartLogger • Aid in creating a FDA 21 Part 11 compliant process • Increase ability to monitor user activities • Maintain version history of camera states • Provide central location for event logging for multiple systems