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Frequently Asked Questions: Mission Performance for Hypersonic Systems

In order to provide a few points of reference for STK users of all levels of expertise, we compiled a few of the most commonly asked questions asked during our recent DME webinar. Please refer to our Help section for more detailed troubleshooting and guidance, or check our News section for more articles exploring the capabilities of STK and AGI’s technology.

Be sure to view our On-Demand Webinar on Mission Performance for Hypersonic Systems on our Events page.
 
What are STK's capabilities in modeling battle management and fire control? Can custom guidance functions be implemented? What about lethality models?
 
Can you touch on any API links/outputs from STK?
 
Where are the NASA papers that were mentioned?
 
Is there a way to model hypersonic reentry from orbit? Is there any manual switchover I would have to tell the software to do since we would be going from a space environment to an atmospheric environment in STK Aviator?

How does STK incorporate my company's IP, and am I able to provide my customized services to customers? Do I retain the rights to my IP when it is incorporated into STK?
 
Are there any other small businesses that incorporate "secret sauce"  or IP, and then provide customized services to their customer? How is that delivered? Is there a way to patent the "secret sauce" part even though it is connected to STK?

You mentioned phugoid oscillations. Does STK model control surface deflections?
 
Can atmospheric consideration be included in the modeling, such as variations in air pressures, temperatures, crosswinds, etc. in real-time?
 
Am I limited to what CFD applications I use to generate data for the hypersonic vehicle?
 
What other kind of environmental effects can we model for communications i.e. BLOS (Beyond Line of Sight). Does this apply to any radar capabilities?
 
Can you make plumes with STK?
 
Q: What are STK's capabilities in modeling battle management and fire control? Can custom guidance functions be implemented? What about lethality models?
A: With STK Aviator and more specifically Aviator Pro, you can model entities dealing with battle management and any guidance logic associated. This is an export controlled capability, please reach out to us at info@agi.com if this is a specific interest.
 
Q: Can you touch on any API links/outputs from STK? 
A: With STK, you have the ability to connect to various programming languages and applications. For example, you can connect STK to MATLAB, Python, Csharp, and Excel to extend your analysis. Some users import their own transmitter models, aircraft models, and other models that are essentially taking some environmental parameters from STK and feeding into their own “secret sauce” plugins at a “per timestep” where the results from the plugin get fed back into STK for use in the next timestep analysis.
 
Q: Where are the NASA papers that were mentioned?
A: Here is the documentation we leveraged from NASA:
  • https://www.nasa.gov/centers/Armstrong/news/FactSheets/FS-040-DFRC.html
  • https://www.nasa.gov/centers/dryden/history/pastprojects/HyperX/index.html
  • https://www.nasa.gov/centers/langley/news/factsheets/X43A_2006_main.html
  • https://www.youtube.com/watch?v=XFb5U7FfvHc
  • https://www.nasa.gov/pdf/67456main_X-43A_Fa.pdf
  • https://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/20010071335.pdf
  • https://www.nasa.gov/pdf/47414main_x43A_mishap.pdf
 
Q: Is there a way to model hypersonic reentry from orbit? Is there any manual switchover I would have to tell the software to do since we would be going from a space environment to an atmospheric environment in STK Aviator?
A: Some users model the space side of this with Astrogator if there are burn maneuvers and more required than just orbits) or SatPro for advanced orbit propagation. At a certain altitude, these models no longer take effect and that is where we switch use the Aviator atmospheric environment. We have helped users set this up via the GUI and also assisted efforts to handle this programmatically via a language such as MATLAB or Python. The manual switchover takes the state of the spacecraft (pos, vel, etc.) at the end of the space flight portion, and leverages that state for the start of the air flight portion.
 
Q: How does STK incorporate my company's IP, and am I able to provide my customized services to customers? Do I retain the rights to my IP when it is incorporated into STK?
A: STK incorporates these through various explicit text files, leveraging a plugin script in a language such as MATLAB or even creating an engine application in C Sharp for example. We have different approaches, but we have had users deploy applications to customers. If you are planning to share your results or even STK scenario with someone else who has licenses, feel free to do so. We do not own any of the work for which you leverage STK or your custom plugins , nor do we own the results that you get.
 
Q: Are there any other small businesses that incorporate "secret sauce" or IP, and then provide customized services to their customer? How is that delivered? Is there a way to patent the "secret sauce" part even though it is connected to STK?
A: The short answer of your first question is yes. Please reach out to us so we can discuss this in more detail, as we have various options for product or data generation/delivery for customers of varying size and with varying needs.
 
Q: You mentioned phugoid oscillations. Does STK model control surface deflections?
A: STK models the surface deflections at a first order level. For example, if you have an aircraft that is landing, it will start to crab if you have also modeled crosswinds. Along with this, STK models different aircraft phases. If you are modeling a Boeing 747 takeoff from JFK airport, you can model the aircraft with the aerodynamic parameters representative of takeoff (i.e. control surfaces deployed, lift and drag different versus in cruise, etc.). With this, you can essentially model the various aerodynamic modes your aircraft has.
 
Q: Can atmospheric consideration be included in the modeling, such as variations in air pressures, temperatures, crosswinds, etc. in real-time?
A: STK can work in a real-time. We can ingest atmospheric data and connect to the NOAA ADDS service for usage, but that is downloaded all at once. This would be “real-time,” from the perspective that we obtained atmospheric parameters of a specific day to use in our analysis. If you are looking to do this type of analysis at a time step per time step basis or higher fidelity, contact us to discuss your needs in greater detail.
 
Q: Am I limited to what CFD applications I use to generate data for the hypersonic vehicle?
A: No, you are not limited to what applications you use. STK has a wide variety of options out of the box, but we allow various sources of data. This includes CFD data, just make sure it is in the proper format. For more help:
https://help.agi.com/stk/index.htm#stk/importfiles-aero.htm
 
Q: What other kind of environmental effects can we model for communications i.e. BLOS (Beyond Line of sight). Does this apply to any radar capabilities?
A: With STK, you can use the Terrain Integrated Rough Earth Model , or TIREM, module. This will allow you to model BLOS comms, and there are similar capabilities available regarding radar. Beyond these options, you can ingest in your own custom algorithms or data to enhance your analysis.
 
Q: Can you make plumes with STK?
A: You can leverage Missile Toolkit (MTK) to model missiles to a higher fidelity, a capability which extends to ballistic missiles, interceptors, and space launch vehicles. With MTK, you can also model various plumes with this that can be re-imported into STK. From there, you can leverage them and see them visualized in the synthetic scene within EOIR. This module is export controlled, so please reach out to us at info@agi.com for more info!
 
Author

Mohammad Syed


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