NASA has created a new digital modeling tool that allows aerospace engineers to innovate in the design of new aircraft, drawing on decades of experience using highly advanced aerospace computer codes.
Using this tool, researchers can create simulations of concept aircraft with technology that has never flown and get detailed data on how it works.
A tool called Aviary for enclosures where birds are kept and studied creates virtual models of the aircraft based on user-supplied information. In this analogy, the aviary is an enclosure and the birds are virtual model aircraft.
Researchers can capture information about the aircraft’s shape, range and other characteristics. Aviary then creates a corresponding digital model of that aircraft.
Jennifer Gratz
Aviary project manager
The aviary is an important step forward. Unlike older aircraft modeling tools, Aviary can be linked with other codes and programs to extend and customize its capabilities.
We wanted to make it easy to extend the code and connect it to other tools, said Jennifer Gratz, who leads Aviarys integration and development. Aviary is purposefully designed to be able to better integrate disciplines.
Aviary is free and available to everyone. The code continues to grow as public contributions are made. The code is on GitHub, along with its key documentation.
Aviary is a descendant of two earlier modeling tools created by NASA decades ago: the Flight Optimization System and the General Aviation Synthesis Program.
However, these older codes were relatively limited in terms of flexibility and detail.
The old codes weren’t designed to handle these more modern concepts like hybrid-electric planes, Gratz said. They saw certain systems as more separate than they actually are in the vehicles we think of today.
Aviary fills this gap, allowing researchers to seamlessly incorporate detailed information that reflects the more integrated and nested systems needed to model newer aircraft.
The team started building Aviary by taking the best parts of existing code and merging them, then adding new code to make Aviary extensible and compatible with other tools.
That’s one of its most important features, Gratz said. Aviary is flexible enough that you can decide what you want to learn more about and then configure it to teach you about it.
Knowing specific, tailored information in advance can inform researchers about the direction in which an aircraft design should go before proceeding with expensive flight testing.
Instead of having to use built-in estimates for certain parameters such as battery charge level, as was done with previous tools, Aviary users can simply use information generated by other tools with battery-specific insights.
Another feature touted by Aviary is gradients. The gradient basically shows how much a certain value affects another value when it changes.
Suppose a researcher is thinking about battery power to successfully power an airplane. Using older systems, the researcher would have to run a separate simulation for each battery power level.
But Aviary can perform this task in a single simulation by taking gradients into account.
You can ask Aviary to determine the battery power to make it worth using. They will fly a simulated flight mission and come back with the results, Gratz said. Older tools cannot do this without modification.
Aviary can simulate all of these concepts simultaneously, no other modeling tool can easily account for existing tools, separate user-introduced tools, and gradients.
Other tools have some of these things, but none of them have all of these things, Gratz said.
In addition, Aviary comes with extensive documentation.
Documentation is another important part of the Aviary, Gratz said. If no one understands the tool, no one can use it. By having a good history of Aviaries development and changes, more people can benefit from it. You don’t need to be an expert to use it.
NASA’s Glenn Research Center in Cleveland, Ames Research Center in California, and Langley Research Center in Virginia contributed to the Aviary.