Real-Time Test Data System modified to further meet AEDC customers’ needs

  • Published
  • By Deidre Ortiz
  • AEDC/PA
AEDC software engineers at Arnold Air Force Base have continued to modify the Real-Time Test Display System to better meet test customers’ needs and make the system even more user-friendly.

RealTDS is a software that enables the project team and test customers to view data in real time. It has been in a side-by-side evaluation with the legacy system for a couple of years but officially went into production this year.

Cameron Liner, chief of Test Information Systems Section for the Test and Communications Branch at Arnold, highly commended the work that’s been done by the developers.

“RealTDS represents the best of AEDC's ability to innovate using a blend of commercial-off-the-shelf and locally-developed solutions,” he said.

Liner also stated that data acquisition is a critical component of what makes AEDC of such great value to the U.S. Air Force and other customers.

“Being able to view data in real time is key to ensuring data quality, maintaining safe operations and increasing our agility to make course corrections during test,” he said.

Chad Dotson, software engineer and part of the RealTDS development team, said major benefits have been gained from the program’s implementation.

"It's available in any test unit on base; from the wind tunnels to engine test cells,” Dotson said. “We're now able to share ideas between mission areas that have not traditionally done so.”
One of these improvements has been to the RealTDS Every Sample Server.

RealTDS web-clients require Enterprise Data Acquisition and Processing System (EDAPS) or eSTARR Every Sample data, which is high-throughput data system.

“What RealTDS does is pull data from eSTARR and feed it directly out to clients,” Dotson said. “It’s able to handle huge amounts of data, up to 100,000 samples a second, so it’s rendering at 40 million data points per second.”

He mentioned that while individual data requirements vary, clients should be able to use RealTDS and have as many of the desired applications up and running with no impact to the server.

“We enabled RealTDS to keep every sample data in larger binary buffers and access it minimally,” Dotson said. “The larger buffers are then transmitted without modification to web clients. As a result, RealTDS web clients are able to receive data at the rate required for Every Sample Displays.”

The system is now set up to handle the large data format without slowing the process down.

“JavaScript garbage collection can be detrimental and excessive when running RealTDS,” Dotson said. “So, the large binary buffers also allow RealTDS client code to use more efficient C-like memory copies and access data directly from these buffers instead of creating extra objects that take up computer memory.”

Jeff Mann, Arnold software engineer who assisted in the further development of Every Sample Display, stated that because a large amount of data is pulled when using the RealTDS program, it uses up a great deal of Central Processing Unit (CPU) time.

“We need the ability to render the data on mid-level PCs without the use of special hardware being added,” he said. “The solution was to eliminate the impact from JavaScript garbage collection by using C-type structures and circular buffers.”

CPU time was also dramatically reduced by pushing most of the processing to the Graphics Processing Unit (GPU) using vertex shaders.

“A vertex shader is used to transform the attributes of vertices, or points of a triangle, such as color, texture, position and direction from the original color space to the display space,” Mann said. “You can now have 40 million points per second on a standard computer with much higher data rates possible with better graphic cards.”

Software engineer Jackson Chandler has helped enhance RealTDS by changing the part of the system dealing with Hypertext Markup Language (HTML) loading of lists.

“AEDC facilities at Arnold needed a new set of modern, real-time data and control panel displays that enable the future Enterprise Instrumentation Data and Controls Architecture vision,” Chandler said. “To provide these displays, the application logic and heavy lifting is heading to the browser.”

To take care of this issue, Jackson created a set of real-time data displays and control panels using modern tools and techniques.

“Common HTML structures used for this include select boxes, lists and tables,” Chandler explained. “When using these default structures with larger data sets, a noticeable performance degradation occurs and a need for a more efficient way to display these arises.”

By using an enhanced loading method, users are able to manipulate the existing structures to act the same as before but with better loading and display times.

Updating test units is made easier and more efficient since all that has to be done to update the application in a test unit is update the server.
“We have been able to achieve a massive increase in performance,” Mann said.

Test analysts have provided positive feedback, noting that RealTDS is a definite improvement from the legacy systems that were being used.

“RealTDS has added new capabilities, which enhance online validation and situational awareness, and has greatly simplified the setup of online displays,” said Joel Nalin, Aeropropulsion test analyst.

Adam Moon, also an Aeropropulstion test analyst at Arnold, added, “RealTDS has done an excellent job of keeping legacy system functionality while providing test analysts with new tools. We are now able to construct more detailed on-line analysis screens that are more unique and flexible than we have previously been provided.”

Liner mentioned that in addition to creating one system for data rendering, RealTDS has also provided a cost-savings for AEDC.

“Because the capabilities are shared across the mission areas, RealTDS provides a lower total cost to the owner for AEDC systems,” he said.