Specification of Disturbances class

1. Overview

1. Functions

This class integrates all disturbances calculation.
All disturbances are initialized in this class.
Their update calculations are called in this class.

2. Related files

src/disturbances/disturbances.hpp
src/disturbances/disturbances.cpp

3. How to use

When you make a new disturbance class, you need to register the new disturbance class in the InitializeInstances function.
If you register your disturbance class correctly, the update function is automatically updated in the Disturbances::Update class, and the disturbance force and/or torque is added for dynamics propagation.

2. Explanation of Algorithm

1. `Update` function

1. overview

This function calls the Disturbance::Update functions defined by each disturbance class.
Generally, orbital disturbances depend on spacecraft position. Some disturbances depend on spacecraft attitude with respect to the disturbance sources. Therefore, there are two update timing in this function.
- When the spacecraft position is updated, all disturbances are updated.
- When the spacecraft attitude is updated, disturbances which depend on attitude are updated.

1. `InitializeInstances` function

1. overview

The instances of all disturbance classes are made and registered to the disturbance list in this function.
The Earth only disturbances are registered when the selected center object is the Earth.

4. References