G-FOLD
├─ demo.png
├─ demo_data.html
├─ demo_traj.html
├─ LICENSE
├─ README.md
├─ requirements.txt
├─ src
│ ├─ plot.py
│ ├─ gfold_util.py
│ └─ lcvx_optimizer.py
├─ vessel_parameters_earth.json
└─ vessel_parameters_mars.json
G-FOLD (Guidance for Fuel-Optimal Large Diverts) algorithm implementation in Python 3. This code first solves a minimum-landing-error guidance problem for a closest landing point and then solves a minimum-fuel guidance problem to reach the landing point.
It's recommended to use venv to set up the environment.
python3 -m venv env
source env/bin/activate
(or for windows, double click "Activate.ps1" in env/Scripts/)
pip install -r requirements.txt
And there you go! We are good to go.
python3 src/gfold_util.py
-h, --help show this help message and exit
-f JSON path to JSON file containing vessel parameters
-n Positive Integer number of intervals (default: 20)
There are two vessel parameters provided already, you can change some of it to see how the trajectory changes accordingly.
Higher N values lead to greater accuracy at the cost of performance, though generally, 20 to 60 suffices.
Utilizes a Golden-section search to determine the optimal flight time.
(Since it's Python, it could be a bit of slow).
- Implement Successive Convexification.
- Generate C code for a better performance.
- Build a control module to run test in Kerbal Space Program.
This project is licensed under the MIT License. See the LICENSE file for details.
For questions or feedback, please create issues!
[1] Acikmese, B., & Ploen, S. R. (2007). Convex programming approach to powered descent guidance for Mars Landing. Journal of Guidance, Control, and Dynamics, 30(5), 1353–1366. https://doi.org/10.2514/1.27553
[2] Blackmore, L., Açikmeşe, B., & Scharf, D. P. (2010). Minimum-landing-error powered-descent guidance for Mars landing using convex optimization. Journal of Guidance, Control, and Dynamics, 33(4), 1161–1171. https://doi.org/10.2514/1.47202
[3] Acikmese, B., Carson, J. M., & Blackmore, L. (2013). Lossless convexification of nonconvex control bound and pointing constraints of the Soft Landing Optimal Control Problem. IEEE Transactions on Control Systems Technology, 21(6), 2104–2113. https://doi.org/10.1109/tcst.2012.2237346