Automated 6DOF Model Generation and Actuator Sizing Within AFSIM 2019-01-1336
The Air Force Research Laboratory has interest in automatically generating the extensive aerodynamic databases essential for six degree of freedom (6DOF) models and the use of 6DOF models for design. To be most useful, automation must include all aspects of producing the database including meshing, control surface deflections, running the CFD solution, and storage of the results. This effort applies newly-developed software to produce the desired results. Firstly, AFRL software called Computational Aircraft Prototype Syntheses (CAPS) allows automated meshing using the Advancing Front Local Reconnection (AFLR) software from Mississippi State University and automated control surface deflection using Engineering Sketch Pad (ESP) software from MIT/Syracuse. CAPS includes the ability to run the NASA CFD code FUN3D and interpret the FUN3D results via an Application Interface Module (AIM). This may sound like a complicated process. However, it is quite simple using a python interface to CAPS called pyCAPS. The automated generation of the aerodynamic database for the 6DOF model is handled by use of a short python script that includes nested loops that handle the numerous CFD runs to capture the combinations of angle-of-attack, sideslip angle, and control surface deflections needed for the database. This database is then paired with an appropriate controller and other information, like propulsion data and mass property data, to form the complete 6DOF model. Of interest is the design of actuators that are attached to the aircraft control surfaces. The 6DOF model is then used to fly the aircraft through an Operational Analysis (OA) scenario in AFSIM (Advanced Framework for Simulation, Integration and Modeling) where maneuvers and environmental conditions like gusts or turbulence are simulated. The entire process is shown to be tractable and accessible.
Darcy Allison, Kyle Shimmin, William Schley, Dean Bryson
US Air Force Research Laboratory, PC Krause & Associates