HOLLY O'DELL, CONTRIBUTING EDITOR
Many machine vision projects start with one premise: to significantly improve upon the accuracy and repeatability of human inspectors. G2 Technologies Inc. fielded such a request when a customer needed an integrator
to create a system that automatically
inspected connector pins used in the
aerospace industry.
Designed for multiple insertions in aerospace craft, the connector pins required a higher level of inspection than their automotive or regular commercial counterparts, which typically have only a single insertion. In aerospace applications, the connector’s contact comprises a pulse of wires from the male and female side that are interwoven to provide multiple contacts, resulting in highly reliable resistance connectors.
G2 Technologies met its customer’s need for an integrator to create a system that automatically inspected connector pins for the aerospace industry.
The inspection system created uses the Linea Mono 8k 13 kHz line-scan GigE camera from Teledyne DALSA because the application calls for high resolution at low cost. “The customer wanted a cycle time of one minute to inspect each connector,” said Craig Borsack, president of G2 Technologies. “The Linea allowed us to acquire and process the images in this time frame.”
In addition to looking at the overall length and width of the connector pin,
the system inspects the pocket in which the wires reside to ensure they are all positioned correctly on the inner
diameter, rather than in between the
inner and outer diameters. The grouping criteria changes based on the male
and female connectors. Since these two connectors have to mate, the inspection criteria ensures that both connectors will mate and make acceptable electrical contact. The camera also counts the number and condition of
wires and checks for debris or foreign
objects in the cavity.
If a defect is found, the system alerts
the operator. If the part is dimensionally
incorrect or the pockets are too small,
the customer will pull the connector
from the line. Missing pins will be replaced, and any debris in the cavity will
be removed.
The aerospace connectors’ inspection
mechanism can detect defects within
±0.005-in. accuracy. The system also looks at the overall length and width of the connector pin, examines the pocket in which the wires reside, and ensures that male and female connectors make acceptable electrical contact.
The detailed inspection of the connector pins requires a robust software platform to support it. G2 Technologies used dTRAK, its manufacturing and test software that automates and standardizes test, measurement, and other manufacturing processes. The main screen provides operators with the current status of the system and the unit under inspection. Users can access features such as the manual interface, where they can troubleshoot the system or make adjustments as needed. The customer found dTRAK especially useful for data management; the software gathers, stores, and analyzes the image data. This allows the customer to run various reports on the results.
Although the inspection system can measure accuracy to within ±0.005 in., lighting the object initially presented a setback. “The wires inside the cavity aren’t finished or cut the same way, and
the orientation on those wires is different for each one of them,” Borsack said. “But the reflection off those wires created hotspots, which wouldn’t allow us to identify between the wires because they were too close.”
A connector’s contact comprises a pulse of wires from the male and female side that are interwoven to provide multiple contacts. The result is highly reliable resistance.
To fix the hotspot issue, G2 Technologies applied a filter and two LED line
lights from Advanced Illumination. The
lights, placed at a 45° angle with the
camera in the middle, allow the right
amount of illumination needed to inspect the object.
The pin inspection, which includes a
Linea camera and LED line lights, plays
a critical role in the overall assembly of the connector pins.
The vision inspection system exceeded the customer’s expectations because the system significantly improved upon accomplishing tasks that humans could not accomplish. “The system can consistently detect defects and [it] performs accurately across shifts and changes in personnel, which had been issues in the past,” Borsack said.