The challenge: Developing a system to remotely access research-quality wind tunnels to conduct real-time, hands-on experiments with tight, closed-loop control.
The solution: Using NI LabVIEW software and the CompactRIO platform for data acquisition and control.
Figure 1: The wind tunnel
GDJ was founded by Jack Gilbert, a former educator whose main goal is to bring science, technology, engineering, and math (STEM) concepts from theory into hands-on practice. During his time teaching at an aviation school, Gilbert found that the study of aerodynamic principles fascinated his students and that many could grasp math and science concepts through his demonstration of real-world connections to mathematical formulas. While using a wind tunnel may not seem like an obvious tool to teach basic math formulas, Gilbert found that many aerodynamic formulas require only simple algebra. Through Mech-Net, he wanted to start a new and innovative service to help schools and universities operate research-grade wind tunnels and engine stands via the Internet. GDJ has developed equipment for educational purposes for a number of years. They operate their laboratory equipment with GUI software to control basic equipment functions.
To provide data with the degree of accuracy required to conduct math formulas requires that the wind tunnel and data acquisition system are of research quality. The wind tunnel must product laminar, low-turbulence airflow and all instrumentation must be extremely accurate. Some institutions were able to purchase them for their programs, but the equipment was expensive and required frequent maintenance, which often made it cost-prohibitive. There were also space, noise and safety concerns. To make it cost-effective, accessing the user interface (UI) gives users the benefits without actually owning the physical hardware and provides multiple users simultaneous access.
The CompactRIO controller runs the entire application. LabVIEW Real-Time is used for the main loops and interfacing with the FPGA, which performs the control and data acquisition. Real-time, deterministic control using the LabVIEW FPGA Module allows for higher feedback rates, which significantly improves stability.
Rather than build the UI on the host computer, we designed it as part of the real-time application running on the CompactRIO. A thin LabVIEW client application is installed on the user’s host computer and, by specifying the remote IP address and system port in the host location, the user can connect to the system and “drive” it as though they are in the lab.