CompactRIO Enables Automated Circuit Board Testing
- Oct 16
- 3 min read
Project Summary
Cyth Systems automated testing of CircaFlex embedded control circuit boards with custom bed-of-nails fixture using NI CompactRIO, LabVIEW and TestStand in 12 weeks.
System Features & Components
Custom bed-of-nails mechanical fixture with pneumatic actuation for reliable probe contact with circuit board test points
NI CompactRIO platform with multifunction I/O, voltage output, and universal analog input modules
LabVIEW-programmed tests orchestrated by NI TestStand to test hundreds of individual components and functional tests in minutes
Automated test reporting and storage of all measurement data and pass/fail status for quality validation
Outcomes
PCBA validation in minutes, greatly improving test throughput
Testing execution time reduced due to integration of mechanical, pneumatic, and data acquisition system onto a unified technology stack
Test system development from proof of concept to production-ready unit delivered within 12 weeks
Technology at-a-glance
Hardware
NI CompactRIO real-time control system
NI C Series Modules
Custom bed-of-nails fixture
Pneumatic actuation system
Embedded PC
Software
Functional Circuit Testing
Circuit boards serve as the center of processing and control in most consumer electronic devices, from smartphones to home appliances. These printed circuit board assemblies (PCBAs) boards require rigorous testing to validate quality and function before distribution to consumers.
Cyth designs and builds systems for the test of PCBAs, so when they found themselves needing to test the PCBAs that their PCBA manufacturer builds per Cyth specifications. They decided to design and build a test system on their PCBACheck reference architecture.
They needed a system that could perform comprehensive electrical measurements, validate individual component function, and sequence hundreds of tests rapidly while maintaining repeatability across production runs.
Mechanical & Data Acquisition Requirements
The mechanical design of the clamshell bed-of-nails included:
Custom pin layouts to interface with specific circuit board contact points
Pneumatic actuation for reliable probe contact
Sophisticated test sequencing capabilities
Without automated testing infrastructure, validating each board's functionality would create production bottlenecks and inconsistent quality control.
Cyth Systems designed and built a bed-of-nails test fixture using NI CompactRIO data acquisition hardware and LabVIEW software for test sequencing and data acquisition.
Mechanical Fixture Design
Custom-fabricated bed-of-nails fixture with pneumatic hood actuation for probe engagement
Spring-loaded electrical probes with unique board layout for contact with circuit board test points when hood lowers into place
Pneumatic control push buttons mounted externally for operator system override
Data Acquisition & Control
Comprehensive Functional Testing
Test Sequencing & Programming
LabVIEW software controls test execution and sequences hundreds of individual tests
Test sequences run with TestStand software to validate board functionality
Automatic generation of test reports to document all measurement data and pass/fail status
Test Process
Operator places circuit board in fixture
Operator actuates control button to pneumatically lower hood, creating contact between electrical probes of fixture and the contact points on the PCBA
Automated test sequences executed with measurement data acquired by cRIO system
Comprehensive report generated and stored upon test completion
Hood releases pneumatically and operator removes tested board
Left: A bed of nails test fixture is used to test Cyth’s Circaflex circuit boards. Right: The NI CompactRIO enables the fixture’s data acquisition.
Cyth’s PCBACheck reference architecture accelerated the development of a comprehensive functional circuit test (FCT) solution for CircaFlex hardware. The final solution accommodated varied capabilities throughout the technology stack:
Custom bed-of-nails fixture tailored to board geometry and functionality
NI CompactRIO and C Series modules for all control, measurement and sensor requirements
Cyth PCBACheck reference architecture software built on:
LabVIEW low-level programming of complex measurement, control and data acquisition
TestStand sequencing of tests programs, report generation and pass/fail reporting on HMI
This approach enabled comprehensive electrical characterization, including operational power testing to validate device performance across varied functionality.
Sustainable Test Design
Cyth developed the complete fixture from proof of concept to finished product in 12 weeks, integrating mechanical design, pneumatic actuation, data acquisition hardware, and test software into a production-ready system.
The system performs functional circuit testing in minutes, reducing test cycle time and overall cost compared to manual validation methods. Cyth expects their CircaFlex test solution to As a robustly architected and flexible test solution, it is expected to ensure CiraFlex product quality and function well into the future.