DMC and our partners designed, manufactured, and programmed several fixed stations and several mobile test stations for use in our client’s controlled burn laboratory. The client has strict reliability and performance requirements for the data acquisition system due to the costly nature of setting up and executing the tests (in both time and expense).
System Requirements Overview
- Data acquisition autonomy
- Data store-and-forward
- Hundreds of IO channels per test cart
- Thermocouple channels
- Digital channels for sprinkler control
- Various analog channels for flow meters, pressure transducers, humidity, etc.
- Data processing
- Upload data to network destination
Hardware
DMC used UEI’s PowerDNA Cube platform to ensure maximum uptime and reliability. The UEI hardware platform is mechanically and electrically ruggedized for operation in harsh conditions and can be configured with a variety of different I/O channels.
Software
Data Acquisition
DMC developed a C++ application (using the Poco framework and ZeroMQ) that runs directly on the Cube’s operating system. The Cube is configured to run a standard Linux kernel with a real-time API, so all development can be done using the familiar GNU toolchain. This application acquires and processes data during a test, and then sends that data to a network location for analysis and long-term storage.
For accurate thermocouple temperature measurements, DMC implemented cold junction compensation (CJC) calculations in the UEI Cube software per the client’s standards.
The data acquisition stations were synchronized using the Precision Time Protocol (PTP) to ensure that data from all stations could be time-aligned and correlated for post-processing.
Data Processing
Acquired data is streamed in real-time to a centralized server using ZeroMQ. There, data streams are processed based on the test’s custom configuration, offering dozens of preset or customizable formulas (e.g., min, max, integral, derivative, mass flow calculations, heat release rate) selected to meet the client’s requirements for that burn test.
Data Storage
To ensure that no valuable test data is lost if the network location is unavailable, data is cached locally in a Sqlite database until it can be uploaded to permanent storage in a SQL Server Columnstore.
Web Application
DMC developed an ASP.NET Core web backend and a React frontend for operators, engineers, and managers to interact with the test station configurations and historical data.
Some notable features of this application include:
- Multiple levels of user authentication to restrict different user types from accessing configuration screens or running and controlling tests.
- Test configuration, including:
- Customizing data channels
- Parameterizing calculations using data channels
- Attaching point-in-time metadata of associated test
- Multiple options for customizable visuals, including:
- Types: table, time chart, heat map, x-y plot
- Selectable time ranges, zoom/pan functions for easy data navigation
- Ability to visualize full-frequency or downsampled dataset
- Support for importing and visualizing legacy test data
Conclusion
DMC’s use of Commercial-Off-The-Shelf (COTS) hardware paired with several layers of custom software integration provided our client with a robust, flexible, and scalable system to meet their testing needs. DMC continues to work with this client to add new features to the system.
Learn more about DMC's Test and Measurement Automation expertise and contact us for your next project.