Accurate Real-Time Extensible Simulations of Dynamic Bodies

A model-based simulation technique has recently been developed and is being transitioned for use in two-body aerodynamic-dynamic problems of interest (slung loads, airdrops) to the vertical lift community. This model, the Georgia Tech Aerodynamics for Bluff Bodies (GTABB), has been shown to accurately predict the behavior of rectangular loads, validated with both computational fluid dynamics and flight test. This paper presents additional validation of the GTABB solver and its six degree of freedom dynamic modeling tool (6DOF) with flight test on new slung load configurations that are connected via either a hook or a gimbal. A new tether algorithm capable of modeling wind-up is demonstrated. In addition, the introduction of a long tether model in 6DOF and a graphical user interface to rapidly build and analyze, visually and quantitatively, tethered load simulations are described. In this paper, a new pre-processor that develops the quasi-steady data tables for arbitrary configurations, COMPlex Aerodynamic Shape Simulator (COMPASS), is introduced with initial verification and validation, demonstrating a concept first introduced in 2011-2012. COMPASS demonstrates the ability to reconstruct the dynamic mechanisms responsible for driving the motion of two-body aerodynamic-dynamic problems.