How to implement various gravity models with precessing reference frames using Aerospace Blockset™ blocks. The Aerospace Blockset blocks are shown in red.

This project shows how to model NASA's HL-20 lifting body with Simulink®, Stateflow® and Aerospace Blockset™ software. The vehicle model includes the aerodynamics, control logic, fault management systems (FDIR), and engine controls (FADEC). It also includes effects of the environment, such as wind profiles for the landing phase. The entire model simulates approach and landing flight phases using an auto-landing controller. To analyze the effects of actuator failures and wind gust variation on the stability of the vehicle, use the "Run Failure Analysis in Parallel" project shortcut. If Parallel Computing Toolbox™ is installed, the analysis is run in parallel. If Parallel Computing Toolbox™ is not installed, the analysis is run in serial. Visualization for this model is done via an interface to FlightGear, an open source flight simulator package. If the FlightGear interface is unavailable, you can simulate the model by closing the loop using the alternative data sources provided in the Variant block. In this block, you can choose a previously saved data file, a Signal Editor block, or a set of constant values. This example requires Control System Toolbox™.

How to estimate a quaternion and model the equations in the following ways: