Origin Technologies Corporation

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App Fastener HS702Inspection problem: Fasteners on the exterior of aircraft must be flush to the surface within a certain tolerance. A fastener that protrudes above or one that is driven below the adjacent surface may adversely affect performance in flight.

Mechanical devices measure the height at one single point on the fastener head and an operator must position the stylus many times on one fastener just to find the highest point. This can be a very time consuming process. 3D mapping of the surfaces is not feasible; it requires expensive equipment, is very time-consuming and the equipment is not practical to use on the flight line.

REQUIREMENTS

App Fastener Screen HS702Measurements - The height and depth of the fastener relative to the surrounding surface must be measured to within thousandths of an inch. Fasteners that measure outside the tolerance range for height or depth must be identified immediately. The read-out must flag any out-of-spec conditions so the operator can mark the fastener or take corrective action.

Instrument - Fasteners are located all over the outer skin of the aircraft, on the fuselage, wings and tail. The measurement instrument must not only be portable, but also lightweight so the operator can inspect any accessible fastener on the plane. A measurement cannot take more than a few seconds because there are hundreds of fasteners to be inspected. Documentation may be required for all measurements or for only those that are out-of-spec.

LASERGAUGE SOLUTION

LaserGauge® System - Depending on the diameter of the fastener and the resolution required, an HS702 sensor with either a 1.2" or 1.9" field-of-view is recommended. This DSP sensor displays the profile of the fastener head in real-time on the LCD so that the operator can make sure that the sensor is positioned correctly over the fastener.

Measurements - Measurements are automatic. The operator positions the laser stripe over the fastener and releases the trigger. The edges of the fastener are identified and the height and/or depth are calculated for both the fastener's left edge and right edge relative to a surface line-fit.

Each measurement takes approximately less than two seconds to complete and to display the results in the data table. SPC or tolerance limits can be specified and any measurements that are outside the spec range are shown in red. The data table is automatically saved for documentation of the measurements taken.

ADVANTAGES REALIZED

Time Savings - Hundreds of fasteners can be inspected in a matter of minutes, and the measurements automatically documented.

Cost Savings - Due to its speed and portability, one LaserGauge® system can be used to support several repair facilities saving the cost of duplicate equipment.

Accurate and Repeatable - With sensor resolution in the thousandths of an inch, measurements are much more accurate than conventional methods.

RELATED APPLICATIONS

App Rivet Screen HS702Angle - The angle of the head of a rivet, screw, bolt or other fastener relative to adjacent surfaces may indicate improper installation. Even though the head is within flushness tolerances, an exaggerated angle can be of importance to aerospace and space vehicles.

LaserGauge® System - Depending on the diameter of the fastener being inspected and the resolution required, an HS702 sensor with a 1.2" or 1.9" field-of-view will accurately calculate the feature angle.

Measurements - The operator pulls the trigger, positions the laser stripe over the feature where desired and releases the trigger. Real-time plots are displayed on the sensor as the operator takes the scan. This allows the operator to view the surface as the laser stripe is being moved into position. If the feature is protruding above the surface or is sunk below the surface sufficient for its edges to be detected, the angle can be calculated automatically, displayed in the data table and can be saved to a data file.

Features - Data is displayed in the table and out-of-spec conditions can be flagged in red. A surface profile as seen on the sensor display can be captured and saved. The scan file can be retrieved to a PC and plotted using any common spreadsheet application.

Our continuing commitment to quality may mean a change in specifications without notice. This system complies with 21 CFR Chapter I, Subchapter J.