This guide showcases how environment models can be added to a simulation In this guide, a basic simulation and a Magnetic Field Centered Dipole and Atmosphere Exponential environment models will be added to a blank level.
Adding Environment Models
In the event graph, to add in a magnetosphere, the Solar System will need to be fetched first. This can be found by calling Get SolarSystem from the level blueprint. Once the system is added, multiple functions can be called. In this case, the Create Magnetic Field Centered Dipole can be called, which will create a Magnetic Field Centered Dipole Planet Model model around the Earth (or another body) with some basic parameters. The default parameters are based on the magnetosphere on Earth.
NOTE
The magnetic field-centered dipole model is an approximation of the Earth’s magnetic field. It is not completely accurate based on positions but it can be used as a benchmark for approximations and measurements. The World Magnetic Model (WMM) model is the more accurate magnetosphere model but uses more computational power to run.
To add in an atmosphere, the Create Atmosphere Exponential function can be called, adding in an Atmosphere Exponential Planet Model around the selected planet. The exponential atmosphere assumes an atmospheric density that decreases exponentially up from the surface of the planet.
NOTE
Similarly, the Atmosphere NRLMSIS Planet Model model is the more accurate representation of the temperature and density variations around the Earth’s surface. This model is also more computationally expensive to compute.
Once the play button is pressed, the Earth will be shown in the level (assuming no other components have been added). There will be no visible difference between not adding any of the models or adding the models to the Earth.
Advanced Models
Each of the magnetosphere and atmosphere models includes an advanced model which are computed and not a simple approximation. These models are the WMM and NRLMSIS models respectively. Unlike the approximation ones, these models are Earth-specific and cannot be used around other planets.
WARNING
Only one atmosphere and one magnetosphere model can be added to a single planet at a time. E.g. If the WMM model is added, the centered-dipole model should not be added to the Earth.
Magnetic Field Example
Open up Demo_MomentumManagement. This demo uses the Magnetic Field Centered Dipole environment models that were added in this guide.
In the Magnetometer Reading” graph on the right, the Magnetic Field that the Three-Axis Magnetometer (TAM) is reading is displayed.
Atmosphere Example
In Demo_OrbitRaising, it is set up with an Atmosphere and Drag Effector by default. The spacecraft is affected by atmospheric drag with the Spacecraft’s SMA slowly decreasing over time.
The atmosphere properties log (bottom left) also shows the local density increasing over time as the spacecraft falls into thicker atmosphere.
