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)




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