Our client already had a test system in place, but the tester (really two test systems testing two different product variants) was becoming obsolete. The tester was old, hardware was failing, and it was getting harder and harder to keep it reliably running. They wanted a new tester to improve reliability, but maintain the functionality of the existing tester to keep the FDA-mandated verification and validation time to a minimum.
The updated end-of-line manufacturing test system maintains the functionality of the old test systems, but with updated hardware and software. The same software is utilized for both the manual test system update and the automated test system update. Our client deployed 6 manual testers and 1 automated tester.
- Improved maintainability and reliability with updated hardware and software
- Maintains existing test system functionality to keep certification time down
There were two variants of the new test system. One was for an older product line that utilized manual test, with an operator that connected/disconnected the UUT, and initiated the test. The other was an automated tester, integrated into a manufacturing machine. Both testers utilized custom fixtures (provided by the client), off-the-shelf NI measurement hardware (selected by Viewpoint), and custom test software (developed by Viewpoint). The software is configurable for both the manual test system and the automated test system.
|Read UUT limits from config file|
|Perform tester self-test|
|Measure UUT output|
|Perform leak down pressure test|
|PLC interface (for automated tester) for start, done, pass, fail|
|Custom test fixture (provided by client)|
|PXI Multifunction I/O Module|
|PXI Digital I/O Module|
|PXI Relay Module|
|PXI Digital Multimeter Module|
|PXI Switch Matrix Module|
*- images are conceptual, not actual
|Touch PC interface / GUI|
|Closed loop parameter control|
|Controlled & emergency shutdown|
|NI analog input cSeries module|
|NI analog output cSeries module|
|NI digital input cSeries module|
|NI digital output cSeries module|
|INTERFACES / PROTOCOLS|
The client already had an existing manufacturing test system in place. They wanted Viewpoint to enhance the tester due to an increase in production volume demand. Viewpoint reviewed the existing test system and noted 3 areas for improvement:
- Automation available in the measurement instruments – most of the test equipment was automatable, via some combination of serial, GPIB, or Ethernet interfaces. Furthermore, some equipment, such as an oscilloscope, had the ability to store and recall setup configurations. The test operators already used these configurations to decrease setup time for the next test step. Most test equipment did not have automated setup.
- Operator time spent on each test step – the client had been through a Lean assessment and had already done a good job of timing operations. However, we specifically noted that the operator was manually connecting to the test points and manually transcribing to paper the measurement results from instrument displays.
- Automating the connections – many types of product models were being tested at this test system. Connecting the test equipment to all sorts of products would require either 1) many types of test harnesses and connectors or 2) a redesign of the products to make test connections simpler and quicker.
The enhanced automated test system included automation of instrumentation interfaces, a test executive to run the test sequences, automated test report generation, and automated test data archiving for the electronic UUT.
- Reduced total test time across several products by an average of ~25%.
- Time to create paperwork was reduced by ~2/3 due to automated data collection.
The enhanced test system included the following updates:
- Test sequence automation
- Automated test report generation
- Automated test data archiving
- Automation of instrumentation interfaces
- Configurable automated test steps associated with each type of measurement instrument. The test operators would create a sequence of steps to setup each instrument and record the resulting measurement. The sequence of steps could be saved and recalled for each product to be tested, so the instruments could be used automatically.
- New programmable meter – integrated the new DMM meter with a programmable interface to replace the one that was not automatable.
- Foot switch integration – Since the connections to the test points were manual, a foot switch allowed the operator to take the measurement and advance to the next step.
The StepWise platform managed the multiple test procedures created for the different products. StepWise also handled creation of HTML reports for every part tested.
|Test Data Archiving|
The device under inspection is essentially an image sensor array used for scanning images in high end commercial-grade scanning printers. The inspection system utilizes machine vision and precision motion control to verify the location & orientation of several parts, with measurement accuracy measured in microns.
|Vision / metrology – pattern match and inspection|
|Motion controller interface|
|Command Recipe Decoder|
|Robot Controller Command Interface|
|HARDWARE (SELECTED & SUPPLIED BY CLIENT)|
|ACS motion control system|
|2-Dimensional Cartesian Robot & Controller|
|LabVIEW RT – for managing the microcontroller functions and overall data collection and safety monitoring|
|Microcontroller application – to provide precision pulsing of the batteries|
|Communicate to the host PC – to both receive pulsing instructions and configurations and to return pulse waveforms for each battery tested.|
|MAIN HARDWARE COMPONENTS|
|PXI chassis & controller|
|PXI analog input modules|
|SCXI multiplexing switches|
|INTERFACES / PROTOCOLS:|