Spacecraft Dynamics And Missions Simulator
The Spacecraft Simulator application has the objective to implement the algorithms used in Orbital Mechanics, Launch Mechanics ,and Entry Mechanics, integrating them inside a GUI application to simplify the analysis.
I decided to adopt the Python language to develop all the algorithms due to the high variety of libraries for scientific applications.
For the Graphical User Interface (GUI) I decided to rely on the QML language (part of the Qt environment) due to its flexibility and the nice and modern fill it can reach.
The Missions that can be simulated are the following:
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Orbit Insertion
Simulate the launch phase when the spacecraft reaches the orbit from ground thanks to a launcher
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Orbit Transfer
Simulate the cost in terms of$\Delta v$ ,$\Delta t$ , and$\Delta m$ of the transfer between a departure and an arrival orbit
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Orbit Propagation
Simulate the propagation of an orbit around Earth due to perturbations
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Interplanetary Transfer
Simulate the transfer between two planets of the Solar System
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Atmospheric Entry
Simulate the re-entry of a capsule
The application is developed in Python 3.11.9 and uses the following main libraries:
matplotlib 3.9.2for data visualizationmplcyberpunk 0.7.1for nice matplotlib plotsnumpy 2.0.2for linear algebra and matrix manipulationscipy 1.14.1for numerical intergrationPySide6 6.8.0.2for the Grafical User Interfaceqbstyles 0.1.4for nice matplotlib plotspyinstaller 6.11.1for executable generation
The front-end is developed in Qt 6.8.0 using the QML language.
The project is structured in the following folders.
dist: contains the application executableimages: README imagesimg: icons and images used in the GUIlib: list of external librarieslib\matplotlib_backend_qtquick: library for integrating matplotlib in QMLlib\pyextrema: library implementing Matlab extrema function
src: back-end of the applicationmissions: available missionssystems: available systemsutility: list of supporting classes
tools: algorithmstools\texture: list of images for different astronomical objects
ui: front-end of the applicationui\components: list of components used in the GUIui\dialogs: list of dialogsui\pages: list of pagesmain.qml: root file of the QtQuick / QML projectqml.qrc: resource file for the QtQuick / QML projectqtquickcontrols2.conf: configuration file for the QtQuick / QML project
generate.bat: batch file used to compile the file qml.qrc in Pythoninstaller.bat: pyinstaller command for the executable creationmain.py: root file of the Python projectSpacecraftSimulator.spec: pyinstaller generated file
Orbital Mechanics for Engineering Students
AuthorsHoward D. CurtisISBN9780080977485SeriesAerospace EngineeringYear2013PublisherElsevier ScienceURLhttps://www.google.it/books/edition/Orbital_Mechanics_for_Engineering_Studen/2U9Z8k0TlTYC?hl=it&gbpv=0
Manned Spacecraft: Design Principles
AuthorsPasquale M. SforzaISBN9780128044254SeriesAerospace EngineeringYear2016PublisherButterworth-HeinenmannURLhttps://www.google.it/books/edition/Manned_Spacecraft_Design_Principles/ntWcBAAAQBAJ?hl=it&gbpv=0
matplotlib_backend_qtquick
pyextrema
qbstyles
mplcyberpunk
From the left menu, it is possible to configure all the properties of the systems and the missions. The systems managed are the following:
LauncherSpacecraftRe-Entry Capsule
The first phase of a mission is to bring the spacecraft to space from Earth. This can be done thanks to a launcher. It is possible to simulate up to 3 stages in series activating them through the switch buttons. The pitchover conditions establish the altitude at which the rocket starts turning with a flight path angle slightly different from the 90 degress at launch. The circular parking orbit conditions allow the user to select the altitude of the target circular orbit, giving the value of the velocity for it.
Each stage is characterized by some parameters used by the Calculate Staging button to make an initial estimate for the parameters the user find on the Launcher page.
By clicking on the Simulate button, the launcher trajectory and data can be visualized and analyzed from the main window. It can be seen, from the example below, that the launcher reached the target altitude with the desired velocity, with a small flight path angle. In addition, the usage of three stages allows keeping the acceleration at small values.
An orbit transfer consists of a set of maneuvers to move a spacecraft from a departure orbit towards an arrival orbit. The user can decide the two orbits and the list of maneuver to simulate an orbit transfer.
First choose among the given celestial bodies.
The second step consists of configuring the Departure Orbit and Arrival Orbit. The orbits can be configured using one of the following representations:
- Cartesian based on the position vector and the velocity vector
- Keplerian based on the orbital elements
- Semi-major axis
- Eccentricity
- Inclination
- Right Ascension of the Ascending Node
- Anomaly of the Perigee
- True Anomaly
- Modified Keplerian based on the following elements
- Periapsis Radius
- Apoapsis Radius
- Inclination
- Right Ascension of the Ascending Node
- Anomaly of the Perigee
- True Anomaly
A preview of the Orbit and the Ground Track can be visioned by clicking on the available buttons.
At this point it is possible to configure the maneuvers for the transfer between the departure and the arrival orbits, among the following ones:
- Hohmann Transfer
- Bi-Elliptic Hohmann Transfer
- Plane Change Maneuver
- Apse Line Rotation From Eta
After the transfer has been evaluated, the values of
By clicking on the Simulate button, the transfer is simulated and becomes visible in the chart.
In the Orbit Propagation mission it is possible to analyze the effects of the following perturbations on an orbit around Earth in a range of dates:
- Drag
- Gravitational
- Solar Radiation Pressure
- Third Body: the user shall select the third body between Moon and Sun
for a given set of initial orbital elements.
By clicking on the Simulate button, you can simulate the orbit propagation. The evolution of the orbital elements with respect to the initial values can be analyzed in the main window.
One of the most interesting aspect of space is space exploration. In this section I explain how the user can simulate an interplanetary transfer.
Under the section Interplanetary Transfer it is possible to analyze/design the interplanetary transfer bewteen two planets of the Solar System, given a Launch Window and an Arrival Window. Once selected the parameters, by clicking on the Generate button the Pork Chop Plot is generated, and can be seen int the bottom right figure. Use the Stop button to finish the generation before it ends.
This is a Pork Chop Plot between Earth and Mars.
After the analysis of the Pork Chop Plot, the actual transfer can be simulated, by choosing the effective departure and arrival dates, and the departure and arrival orbits around the planets. The following is a simulation for a tansfer between Earth and Mars.
The Atmospheric Entry problem studies what happens when an object (e.g. capsule carrying extraterrestrial meterial) re-enters on Earth.
Under the section Atmospheric Entry it is possible to set up the parameters needed to simulate a capsule re-entry: some of the data are also present in the Capsule section. The user can activate / deactivate the usage of the parachute. Under the results sub-section the user can analyze the Impact Velocity at ground.
After you have decided the Entry Conditions, by clicking on the Simulate button, the simulation is executed and the results shown on the charts below. Each chart represents a peculiar parameter of the analysis:
- Velocity vs Time
- Acceleration g's vs Time
- Altitude vs Downrange Distance
- Fight Path Angle vs Time
- Stagnation Point Convective Heat Flux vs Time
- Stagnation Point Radiative Heat Flux vs Time
- Altitude vs Velocity
