An open-source C++ framework for spacecraft simulation, guidance, navigation and control.
Modern • Modular • Extensible • Research-Oriented
The Spaceflight Dynamics Framework (SDF) is an open-source C++ framework for developing modular aerospace simulation software.
Rather than focusing on a single simulation, SDF provides reusable building blocks for 6-DOF spacecraft dynamics, propulsion, guidance, navigation, control, telemetry and visualization.
Its mission is to provide a platform where aerospace enthusiasts, students, researchers and developers can learn, experiment and develop modern aerospace software while following clean software engineering principles.
SDF is not just a simulation. It is intended to become an extensible platform for education, experimentation and scientific research in spacecraft dynamics and aerospace software engineering.
The repository currently contains a demonstration application showcasing the capabilities of the framework including full six-degree-of-freedom spacecraft dynamics, autonomous lunar landing and a modular cockpit architecture.
Future applications can reuse the same framework architecture while targeting completely different spacecraft missions and simulation scenarios.
Current SDF demonstration application
- Full 6-DOF rigid-body dynamics
- Quaternion-based attitude propagation
- Modular translational & rotational physics
- Modular simulation backend
- Dedicated interface layer
- Frontend / backend decoupling
- Telemetry Mapper
- Telemetry DTOs
- Eigen-based mathematics
- JSON spacecraft configuration
- Adaptive descent controller
- Multi-engine propulsion system
- Individual RCS thruster simulation
- Qt cockpit application
SDF layered architecture overview
Further documentation:
- Core Data Flow Documentation — architectural data flow diagrams and subsystem ownership
https://www.aerospace-simulation.dev/simulation/architecture/
SDF is intended to become an experimental environment for aerospace research.
Research topics include:
- optimal control
- GNC
- adaptive controllers
- numerical integration
- simulation stability
- spacecraft dynamics
- optimization
- telemetry analysis
- controller benchmarking
- rigid-body dynamics
- attitude dynamics
- spacecraft simulation validation
SDF has reached Code Freeze for the first SDF Light release.
The implementation scope of the initial 6DoF Core Simulation is considered feature-complete. Development is now transitioning from feature implementation to release qualification, verification and acceptance testing.
For SDF Light, Code Freeze means:
- no new
D-issues(development/features) are planned for the release - the production code baseline is kept stable
T-issuesare now the primary focus for testing, verification and release acceptanceB-issuesmay still be created and fixed if acceptance testing reveals reproducible defects- non-critical enhancements and architectural extensions are deferred to later releases
The current SDF Light baseline includes:
- Full translational rigid-body dynamics
- Full rotational rigid-body dynamics
- Quaternion-based attitude propagation
- Quaternion-based attitude stabilization
- Modular main-engine and RCS propulsion
- Force & torque aggregation
- Deterministic fixed-step numerical propagation
- Multi-frame coordinate architecture
- Landing-site-relative initialization
- Structured telemetry export
- Qt cockpit demonstration application
The automated test infrastructure introduced with T03 is now established and provides:
- GoogleTest-based C++ tests
- CTest integration
- separated unit, integration and verification test structure
- a reproducible local PASS / FAIL workflow for release qualification
The project is currently in the acceptance-test phase for SDF Light. The remaining work is focused on analytical reference cases, end-to-end verification, regression testing and the final Milestone 1 acceptance.
SDF Light is approaching its first public release.
No additional functionality is planned for the release baseline. Remaining production-code changes should only result from confirmed defects found during verification or final release-candidate testing.
The Spaceflight Dynamics Framework follows an incremental development strategy. Each release expands the framework while maintaining a stable architectural foundation.
SDF development roadmap and release strategy
The long-term vision is to extend the existing 6-DOF simulation core with:
- orbital mechanics
- advanced GNC algorithms
- ROS2 integration
- replay & telemetry analysis
- controller benchmarking
- planetary mission scenarios
- advanced sensor models
- environmental models
See the installation guides in the docs folder.
git clone https://github.com/gerd-lrt-dev/spaceflight-dynamics-framework.git
cd spaceflight-dynamics-framework
mkdir build
cd build
cmake ..
cmake --build .Comprehensive documentation is available on the project website.
https://www.aerospace-simulation.dev
Framework architecture and software design.
https://www.aerospace-simulation.dev/simulation/architecture/
Overview of the current demonstration application.
https://www.aerospace-simulation.dev/simulation/demo/
Physics & Motion
https://www.aerospace-simulation.dev/mathematics/physics/
Coordinate Frames & Transformations
https://www.aerospace-simulation.dev/mathematics/coordinateTransformation/
Main Engine Model
https://www.aerospace-simulation.dev/mathematics/thrust/
Reaction Control System
https://www.aerospace-simulation.dev/mathematics/RCSBasicModel/
Adaptive Descent Controller
https://www.aerospace-simulation.dev/mathematics/adaptiveDescentController/
Impact & Structural Integrity
https://www.aerospace-simulation.dev/mathematics/impact/
Meet the people behind the project.
https://www.aerospace-simulation.dev/team/
Whether you're an experienced aerospace engineer, a software developer, a researcher, a student or simply curious about spacecraft simulation — contributions are always welcome.
SDF is an interdisciplinary project, and contributing means much more than writing code. There are many ways to get involved:
- develop new simulation models
- validate and benchmark physical models
- improve numerical methods
- design and evaluate control algorithms
- test and benchmark new features
- improve existing software components
- enhance the user interface
- extend the documentation
- discuss ideas, report bugs and suggest improvements
If you would like to contribute, please have a look at:
- CONTRIBUTING.md
- Installation Guidelines
Every contribution—whether it is code, validation, documentation, testing or engineering expertise—helps make SDF a better platform for learning, experimentation and aerospace research.
We'd be happy to have you onboard.
This project is released as open-source software.
See the LICENSE file for licensing information.
If you are interested in spacecraft simulation, aerospace software engineering or simply want to learn something new, you're invited to join the journey.