VisionGauge® Pattern Matching Tools to Identify, Locate, and Verify Objects & Features

VisionGauge® has powerful pattern matching tools adapted to solve a wide range of applications. These tools can be used to identify and accurately locate objects in images and features on objects. There are absolutely no limitations on the number of objects and features. They can act as feature and object recognition tools and detect multiple instances of parts and features.

VisionGauge’s® pattern matching tools:

  • Are adapted for arbitrary objects & features
  • Are robust to additional parts & features in the image
  • Can handle partial occlusion and are robust to partial deformations
  • Are suited to arbitrary orientations
  • Can deal well with variations in illumination and are tolerant to noise

Their performance has been optimized and they are fast. They are very flexible and widely-applicable. And they are very easy to setup and very easy to use. VisionGauge’s® pattern matching tools are perfect to locate objects and features and carry out defect detection.

Screw pattern matching pattern
Pattern matching tools examples

Download a copy of this Application Note in .pdf format.

Contact us with your application requirements, and visit our Applications page for examples of applications we can solve.

VisionGauge® Edge Break Measurement Tool

An edge break consists in smoothing a corner that otherwise would be too sharp, most often using either a chamfer or a radius. The objective is generally to ensure part longevity, safe handling, and proper performance.

sharp edge - edge breaks

Sharp Edges

Edge Breaks - Chamfered edges

Chamfered Edges

Edge Breaks - Rounded edges

Rounded Edges

There is no GD&T symbol for edge breaks and they are not referenced in the ASME Y14.5 standard. Nevertheless, VisionGauge® systems are perfectly suited for measuring edge breaks, either using overlays or the new VisionGauge® edge break measurement tool.

VisionGauge®’s edge break measurement tool is suited to sharp, rounded, and chamfered edges. The tool automatically locate the edge break’s tangent points, to very high accuracy, and there are no limitations as to the angle at which the edges meet.

VisionGauge®’s edge break measurement tool is robust and filters our spurious noise (i.e. disregards point imperfections and defects such as contamination, “mouse-bites”, etc…) to obtain the true best-fit line. Measurement results are fast, repeatable, and completely operator-independent.

The VisionGauge® edge break measurement tool also has user-selectable parameters for demanding applications (e.g. the allowed “Delta” variation in distance from the calculated line before locating an edge break, etc…).

Automated edge break measurements - 1
Automated edge break measurements

This tool is available for both manual and fully-automated measurements (i.e. it can be included in an automated program). The edge break location can be saved as a datum and re-used in later measurements for fast and highly-accurate program results.

VisionGauge®’s edge break measurement tool is fully-integrated into the VisionGauge® Digital Optical Comparator’s software:  This means that VisionGauge’s® multi-level password protection will be available, reports can be produced, all of the data & results can be databased, sent to external applications, etc, etc, etc…

Contact us with your application requirements, and visit our Applications page for more examples of applications VisionGauge® Digital Optical Comparators can solve.

VisionGauge® Motorized Systems and Automation Features

Auto-Mosaic Tool (Auto-Stitch or Automatic Image Stitching)

VisionGauge®’s “Auto-Mosaic” Tool (or automatic image stitching) allows you to automatically build a very high-resolution image of areas that are larger than your system’s optical field of view. This feature is available in Motorized Stage systems.

VisionGauge®’s “Auto-Mosaic” Tool is very easy to use:  Simply select two opposite corners of the area that you are interested in and press the “Scan” button. VisionGauge® does everything else! You can also tell VisionGauge® to periodically refocus the image or ignore a certain number of rows & columns of pixels on each of the different borders of each field-of-view. This allows you to compensate for uneven illumination, for example.

Finally, please note that the maximum size of the resulting image (and thus the maximum area that you can scan at any one time) is only limited by your computer’s system memory.

Download a .pdf with information about VisionGauge®’s “Auto-Mosiac” tool.

High-Accuracy Automated Volume Measurement Tool

VisionGauge® high-accuracy automated volume measurement software tool is:

  • Extremely easy to use
  • Fast
  • Produces very repeatable measurements, and
  • Yields operator-independent results

It produces:

  • a numerical value of the measured volume (you can select different metric or imperial units),
  • 3D surface plots (with an adjustable mesh coarseness, with either wire-mesh or surface rendering, and either with or without illumination modeling). These automatic 3D surface plots – which can be viewed from any perspective and rotated along all 3 axes – are very useful for properly viewing the sample from all angles and getting a good understanding of it.

The 1st image is “what the camera sees”. The other images are different automatic 3D plots of the computed surface.

Of course, VisionGauge®’s fully automated high-accuracy volume measurement tool is perfectly integrated with VisionGauge®’s wide range of easy-to-use statistics, data collection, databasing, and reporting tools.

Download a .pdf with information about VisionGauge®’s full-automated volume measurement tool.

VisionGauge® Video Sequence Capture, Live Image Overlays, & Additional Features

VisionGauge® Support for DXF Format CAD Files With “Part Tracking”

Powerful & easy to use:

VisionGauge®’s Live Image Overlay Builder supports DXF-format CAD files. When you read a DXF file into the Live Image Overlay Builder, VisionGauge® can automatically scale the drawing to match up with the system calibration. This means that if the item measures one inch in the CAD drawing, it will appear on the screen as a one-inch object under the camera.

This is the perfect tool to use when comparing a part against its CAD drawing; VisionGauge® scales the CAD drawing appropriately and draws it “on top” of the part! VisionGauge®’s Live Image Overlay software tool with DXF-format CAD file support allows you to quickly determine how well a part matches up with its CAD file definition.

And when you use this tool with a stage (either manual or motorized), the overlay can move with the part. By having the overlay “track the part” in this way, you can carry out inspections and compare the part with the CAD overlay drawing at higher magnifications, outside of the field of view.

Other display options are also available: for example, you can scale the CAD drawing to fit inside the image or you can specify your own scaling coefficient.

For more advanced CAD overlay handling and part comparison, including our patented CAD Auto-Pass/Fail™ and CAD Auto-Align™ features, learn about our ground-breaking VisionGauge® Digital Optical Comparator systems.

Download a .pdf with information about VisionGauge®’s DXF overlay tools

Full Frame-Rate Video Sequence Capture Tool

VisionGauge®’s powerful Video Sequence Capture tool allows full frame-rate video capture (or slower, if specified by the user) to system memory. Once captured to memory, the video can be played back, modified, saved to disk, and retrieved later on, etc… The amount of video that can be captured (i.e. duration) is only limited by system memory.

VisionGauge® can save the video to disk as a sequence of individual bitmap images or as an “*.avi” movie file that can be played by other media applications. This tool is especially useful for time-dependent processes, motion tracking, etc…

In all cases, the video is captured and saved at full resolution and without compression, in full color and at full video frame-rate.

VisionGauge®’s Video Sequence Capture tool supports both analog and digital cameras.

Download a .pdf with information about VisionGauge®’s Video Sequence Capture tool.

Programmable Computer-Controlled Illumination

VisionGauge®’s programmable computer-controlled illumination option:

  • Is extremely easy to setup and configure
  • Is easy-to-use and has a very simple and intuitive interface
  • Allows you to control up to 4 individual light sources
  • Is fully programmable (i.e. allows you to program different repeatable light configurations & intensities at different measurement points)
  • Proven to increase measurement repeatability in machine vision inspection
  • Is perfectly integrated with all of VisionGauge®’s other tools

Download a .pdf with information about VisionGauge®’s programmable computer-controlled illumination.

Motorized Zoom and Focus Optical Systems

VisionGauge® includes built-in support for motorized optical systems. With VisionGauge®, you can motorize both the zoom and focus axes, using either stepper motors or encoded servo-motors. VisionGauge® has a simple and intuitive interface that gives you full control over your motorized optical system.  Motorized optics are available in both operator-driven and fully-automated systems.

Measure at ANY zoom position over the full zoom range:

With encoded motorized zoom optics, VisionGauge® is continuously aware of the system’s optical magnification as you zoom in and out. This means that VisionGauge® is able to:

  • Carry out high-accuracy measurements at any time over the full zoom range of the optics
  • Go to programmable and repeatable zoom positions

VisionGauge®’s calibration procedure for encoded motorized zoom optics is very straightforward. The user begins by indicating the number of calibration points that he wants to enter and VisionGauge® distributes these points uniformly over the full zoom range of the optics. For each calibration point, VisionGauge® then brings the optics to the appropriate zoom position and prompts the user to carry out a simple field-of-view calibration. Once all of the points have been entered, VisionGauge® saves the calibration data to disk. This calibration data can be password-protected. VisionGauge® will then automatically read-in the calibration data on startup. And even though you only need to calibrate VisionGauge® at a limited number of zoom positions, VisionGauge® is able to carry out high-accuracy measurements at any position over the full zoom range of the optics by interpolating very accurately between the calibration points.

Motorized optics are another powerful tool that VisionGauge® puts at your disposal to easily and effectively solve difficult inspection and measurement applications.

Download a .pdf with information about VisionGauge®’s Motorized Zoom and Focus Optics.

VisionGauge® Counting & Sizing and Image Analysis/Processing Tools

VisionGauge® Counting & Sizing (Blob Analysis)

Reliable object thresholding and analysis:

VisionGauge®’s powerful and easy-to-use “Counting & Sizing” feature will let you analyze particles, grains, inclusions, cells, and other similar objects.

You can separate the objects from the image background based on either red, green, or blue channel values as well as luminance, intensity, hue, or saturation values. Using both lower and upper limits, you define where the objects are located in the histogram. Once you have set this range, you can also set limits on the object area. Once again, both lower and upper limits are available (i.e. you can instruct VisionGauge® to only consider those objects that have an area greater or equal to a certain lower limit and smaller or equal to a certain upper limit).

Counting & Sizing

You can define a region of interest in order to limit the “Counting & Sizing” tool’s scope to a user-selected portion of the image rather than the entire image. These limits can be entered manually or drawn directly onto the image. This blob analysis software tool can also be instructed to remove individual particles from the sample and to disregard any objects that touch region of interest’s borders.

The “Counting & Sizing” tool can also be used to obtain information about individual objects. You can easily obtain the area, projection, and the equivalent diameter of an object simply by clicking on it.

All of these adjustments are very easy to carry out because, as you work and refine the different parameters, VisionGauge® interactively updates all of the numerical results and graphs as well as the image of the individual objects. Results include the number of objects, the minimum, maximum, average, and median object areas, as well as the object area distribution curve.

VisionGauge® Counting and Sizing

Download a .pdf with information about VisionGauge®’s Counting & Sizing tool

Image Processing Software Tools for Image Analysis

Powerful & easy to use:

VisionGauge® has a broad set of powerful and easy-to-use image processing software tools that allow you to “clean-up” images that cannot be properly dealt with by the image analysis tools and transform them into imagery that can be successfully analyzed reliably.

For example, the images below illustrate the dramatic improvement obtained by proper image pre-processing using VisionGauge®’s noise reduction and uneven illumination correction tools.

As can be seen in Image 2, it is impossible to apply a unique threshold value across the entire image to successfully extract the objects from the image background. However, Image 5 shows that – using VisionGauge®’s Counting & Sizing tool – the objects can be separated easily & reliably from the image background after applying VisionGauge®’s noise reduction & uneven illumination correction tools.

Download a .pdf with information about VisionGauge®’s Image Processing For Image Analysis software tools.

Focused-Based Image Blending (“Perfect focus”)

You can use this tool to combine two or more partially-focused images into one fully-focused image! This is extremely useful in applications where your instrument’s optical depth-of-field is less than the height of the features and topography on the sample.

This fully-automatic image focus blending tool works on color as well as greyscale images, and there is no limit on the number of component images that you can use.

Here’s a simple example:

1st partially-focused component image
2nd partially-focused component image: (the IC is out of focus and the board is in focus)
Resulting fully-focused image

With this tool, you can choose from 4 different automatic image blending algorithms:

  1. Best focus
  2. Weighted focus
  3. Power-weighted focus, and
  4. Adaptive (i.e. neighborhood-weighted best focus).

In practice, the 4th algorithm generally gives excellent results (and is always active by default), but the other 3 schemes are also available to give advanced users a maximum level of flexibility.

Download a .pdf with information about VisionGauge®’s Focus-Based Image Blending Tool.

VisionGauge® Measurement Tools, Statistics, & Reporting Features

High Precision Measurements and Measurement Statistics

Powerful & easy to use:

VisionGauge® is a powerful tool for non-contact visual measurements. It uses advanced edge-detection technology that produces sub-pixel accuracy, increases measurement repeatability and virtually eliminates operator dependent measurement error.

VisionGauge® is very simple to use and supports a wide range of measurement tools: from simple point-to-point measurements, diameters, radii, angles, and XY calipers to skew-corrected parallel hashlines and powerful and flexible marker-to-marker measurements, as well as fully-automated measurement software tools (e.g. line width, area calculation, and more).

Computing measurement statistics:

You can use VisionGauge® to compute measurement statistics, including sample mean, median, minimum and maximum, variance and standard deviation, as well as process capability statistics (i.e. Cp and Cpk). With VisionGauge®, it is easy to manage all of your data (i.e. images, measurements and statistics):

  • Link, store and recall all of your data with the easy-to-use integrated database and report generator
  • Save the information to disk
  • Print the information
  • Seamlessly transfer the information to other application

Example:

Here is an example of a simple marker-to-marker measurement. In this case, we are measuring from the center of the hole to the center of the pad. X, Y and “straight line” distances are shown:

Download a pdf with information about VisionGauge®’s Measurement Tools and Statistics Toolbox.

VisionGauge® Measurement Toolset

VisionGauge® has a wide selection of easy-to-use and powerful machine vision software measurement tools, including:

  • Point-to-point (i.e. “True Distance”) measurement
  • Horizontal distance
  • Vertical distance
  • Distance between arbitrary parallel lines (i.e. with built-in skew correction)
  • Simultaneous XY measurements
  • Diameter (using 3 or more measurement points)
  • Radius (also using 3 or more measurement points)
  • Angle measurement
  • Orthogonal line width (i.e. automated measurement tool)
  • Arbitrary line width (i.e. automated measurement tool)
  • Automatic circle (i.e. automated measurement tool)
  • Automatic angle (i.e. automated measurement tool)
  • Pathline measurement
  • Area measurement
  • Z measurements
  • Distance between a point and a plane
  • The area of a thresholded object
  • The equivalent diameter of a thresholded object
  • The equivalent radius of a thresholded object
  • Maximum X and Y dimensions of a thresholded object
  • Marker-to-marker measurements, where markers can be:
    • A point
    • The center of an XY rectangle
    • The center of a circle
    • The center of an arbitary triangle
    • The center of an arbitrary 4-vertex feature
    • The center of an arbitrary 5-vertex feature
    • Line midpoint
    • Orthogonal to line
    • Zero position
    • The centroid of a thresholded object
  • Advanced, fully-automated volume measurement tool
  • etc…

VisionGauge®’s Enhanced Database Search Tools
with “Thumbnail” Preview Image Gallery

VisionGauge® allows users to create customized measurement reports, storing an image, measurements, and text descriptions for each report. Reports can be used as templates for operators to fill in or standalone inspection reports for each part saved to the VisionGauge®’s integrated database.

You can use VisionGauge®’s enhanced “Database Search” tools to call up all of the reports in VisionGauge®’s report database that contain a specific search string (for example: a date, an evocative keyword, a specialized term, etc…). These enhanced “Database Search” tools work seamlessly with VisionGauge®’s integrated Report Generator and Database.

To carry out a search, simply type-in a search string and VisionGauge® shows you all of the reports in which it can be found, sixteen at a time. For each matching report, VisionGauge®’s “Database Search” tools display a thumbnail preview image, along with two “key field” strings. Then, when you click on the image of the report that you’re looking for, VisionGauge® retrieves it from the database and loads it into the Report generator.

Specifying Tolerances for VisionGauge®’s Patented CAD Auto-Align™ & CAD Auto-Pass/Fail™ Tools

VisionGauge® offers two ways to specify tolerances. The first is to simply enter them directly in the VisionGauge® software. VisionGauge® has a simple and intuitive interface to allow you to do this quickly and easily. It is extremely flexible and supports the common bilateral “plus / minus” tolerances as well as “plus / plus” and “minus / minus” tolerances. Furthermore, VisionGauge® allows you to specify both uniform and linearly variable tolerances. All parameters can be set on an entity-by-entity basis and VisionGauge®’s “snap to entity” tool makes it easy – even in very busy drawings – to quickly set everything up.

VisionGauge® can also read in tolerances directly from CAD files. In this case, the tolerances can vary arbitrarily, i.e. uniform, linearly or otherwise… This is the absolute fastest way to setup CAD Auto-Align™ and CAD Auto-Pass/Fail™ operations. Everything can be setup in under a minute, with time to spare.

In both cases, VisionGauge® offers a wide range of display options, including the following:

  • hiding the nominal (to avoid clutter)
  • displaying the maximum deviation from nominal over either all or certain user-specified entities
  • displaying the search range
  • a wide range of line styles and colors as well as unique display modes
  • etc…
  • CAD Auto-Pass/Fail tolerances specified for an orthopedic plate

VisionGauge Digital Optical Comparator Featured Software Tools

The VisionGauge® OnLine software drives the VisionGauge® Digital Optical Comparator. This powerful machine vision software for automated inspection, verification, and data collection includes state-of-the-art vision tools for defect detection, pattern matching, automated measurement, optical character recognition, blob analysis, and much more. VisionGauge® OnLine features exclusive tools for use with our VisionGauge® Digital Optical Comparators, many of which are listed below.

The VisionGauge® Digital Optical Comparator's CAD Auto-Align™ tool automatically aligns the CAD data to the part.

 

The VisionGauge® Digital Optical Comparator’s ground-breaking CAD Auto-Align™ tool automatically aligns the CAD data to the part, drastically reducing inspection times and obtaining increased accuracy.

The VisionGauge® Digital Optical Comparator's patented CAD Auto Pass/Fail™ tool allows you to automatically determine, very accurately and in real-time, if a part is within tolerance.

 

The VisionGauge® Digital Optical Comparator’s patented CAD Auto Pass/Fail™ tool accurately computes and displays, in real time, a part’s deviation from nominal, to automatically determine with a Pass/Fail result if a part is within tolerance.

Bone screw teeth verification with the VisionGauge® “Tooth Checker™” tool

 

VisionGauge®’s powerful and innovative new Patent Pending “Tooth Checker™” tool automatically locates, to very high accuracy, the crests and / or roots of  a part’s teeth or threads and determines if they are within their tolerance band.

CAD Auto-Pass/Fail inspection on a condyle implant

 

VisionGauge® OnLine has an easy and intuitive interface for specifying tolerances on CAD overlay files used with the CAD Auto-Align™ and CAD Auto-Pass/Fail™ tools. You can also read-in tolerances directly from the CAD file. Multiple tolerance types are supported with different display options.

True Position measurement of a cylindrical feature inspected using Cartesian basic dimensions

 

Easily define features with datums, then automatically determine if the Actual occurrence of a feature falls within the Nominal’s allowable tolerance zone with VisionGauge® OnLine’s True Position measurement tool (Position Tolerance).

Automated edge break measurementsVisionGauge®’s Edge Break Measurement tool automatically locates to high-accuracy, the edge breaks of lines – including sharp, rounded, and chamfered edges. Lines are automatically calculated at any orientation and there are no limitations to the angle at which the edges meet.

pattern matching tools - sampleVisionGauge® includes powerful pattern matching tools useful in solving a wide range of applications. These robust tools can quickly and accurately identify and locate objects and features without limitations.

True Position Measurements (Position Tolerance)

VisionGauge® OnLine programs can take advantage of our new True Position measurement tool. True Position (sometimes referred to as “Position Tolerance”) is the total permissible variation that a feature can have from its “true” position. VisionGauge® OnLine’s approach to True Position allows a user to define a Nominal feature whose position is compared to the Actual occurrence of that feature. Features are defined using datums that have been set in previous program steps, using VisionGauge® OnLine’s rich measurement toolset to specify points. Nominal features can be defined using either Cartesian or Polar coordinates, which makes this software tool versatile in solving different types of applications. Nominal features can also be offset from a position using Basic Dimensions in the current measurement units.

VisionGauge® Online presently supports Cylindrical (point location) and Non-Circular (line) features of size. The Nominal tolerance zone is displayed along with the Actual feature location. As with all VisionGauge® Online measurements, results – including a Pass/Fail result – can be automatically output to Data Groups and other reporting options.

True Position – Cylindrical (Cartesian)

True Position measurement of a cylindrical feature inspected using Cartesian basic dimensions
True Position measurement of a cylindrical feature inspected using Cartesian basic dimensions

In the above example, the hole’s nominal center point is defined precisely 1.250 inches vertically and horizontally from the corner of the part. The actual center of the hole is located, and the software automatically computes the True Position of the feature and reports a Pass/Fail result based on the diametric tolerance zone defined.

True Position – Cylindrical (Polar)

True Position measurement of a cylindrical feature inspected using Polar basic dimensions
True Position of a cylindrical feature inspected using Polar basic dimensions

In this example, the hole’s nominal center point is defined precisely at 60 degrees clockwise on a radius of .750 inches centered about the part’s center hole. The actual center of the hole is located, and the software automatically computes the True Position of the feature and reports a Pass/Fail result based on the diametric tolerance zone defined.

True Position – Non-Circular (Polar)

True Position of a non-circular feature inspected using Polar basic dimensions
True Position of a non-circular feature inspected using Polar basic dimensions

In this example, the nominal centerline is defined precisely at 45 degrees clockwise and centered about the part’s center hole. The actual centerline of both teeth on the spline is located, and the software automatically computes the True Position of the feature and reports a Pass/Fail result based on the tolerance zone defined (equidistant and parallel to the nominal centerline).

Please contact us with your application requirements, and visit our Applications page for more examples of applications we can solve.

True Position Measurements (software feature)

VisionGauge®’s Patent Pending “Tooth Checker™” Tool

VisionGauge®’s Patent Pending “Tooth Checker™” tool is specially adapted to check parts
with teeth

VisionGauge®’s powerful and innovative new Patent Pending “Tooth Checker™” tool automatically locates, to very high accuracy, the crests and / or roots of  a part’s teeth or threads and determines if they are within their tolerance band. It can also determine all other part characteristics, such as tooth pitch, thread depth, major & minor diameters, etc…

Bone screw teeth verification with the VisionGauge® “Tooth Checker™” tool
  • Fully automated
  • Completely independent of part orientation & clocking
  • With a rotary stage the crest and root points can be used to calculate part runout
  • Can also be applied to parts that are larger than the field-of-view
  • The tool is usable in both manual and fully-automated modes (i.e. within an automated program)
  • The tool produces a PASS / FAIL result (which can be exported and used in all of the same ways as the current PASS / FAIL results) and also shows where the part passes and where it fails
  • Supports linearly variable tolerances, plus/minus tolerances, plus/plus tolerances, minus/minus tolerances, etc…
  • Smart “Adaptive Thresholding” automatically disregards point imperfections

Perfect for quickly and accurately checking:

  • Bone screws
  • Medical rasps
  • Gears
  • Fluted Instruments
  • Threads & fittings
  • Etc…
Medical Rasp Inspection and Verification

The Tooth Checker tool can check that either crests, roots, or both, are in tolerance

Automatic thread inspection: Automatically detect crests and roots in major/minor diameters of teeth or screw threads with VisionGauge®’s new Patent Pending “Tooth Checker™”.

Quick & Easy to Set Up!

VisionGauge Tooth Checker Nomenclature

Using the crest & root points that the Tooth Checker tool has found, it can then automatically determine all other part characteristics

Download a .pdf version of this VisionGauge® Digital Optical Comparator Application note here.