This repository contains the Python code used for compiling the paper "Swinging Motion of a Kite with Suspended Control Unit Flying Turning Manoeuvres" that is published on Wind Energy Science [1] (preprint).
The code uses experimental flight data of Kitepower B.V. to impose the measured flight path of the wing. A specific figure-of-eight cross-wind manoeuvre of the 65th pumping cycle is thoroughly analysed for which the flight data is provided in 20191008_0065_fig8.csv. Moreover, ten pumping cycles are studied in the paper and the corresponding data files are included in the cycles directory. The full flight data can be accessed at [2].
Two models are used in this analysis: the steady-rotation-state and dynamic models, based on the papers of Williams [3] and Zanon et al. [4], respectively. The dynamic model is implemented using CasADi [5] to efficiently solve the motion of the kite and tether. Moreover, CasADi is used to pre-process the recorded kinematics of the wing using an optimization problem.
The code is tested in Python 3.11. It is recommended to use Anaconda for setting up the environment. The following instructions are for Linux.
We assume that a version of Anaconda is installed on your machine. Set the name of your environment in environment.yml by a name of your choice and create the virtual environment using the following command:
conda env create -f environment.yml
Activate the new environment to use it:
conda activate [env_name]
in which [env_name] should be replaced by the chosen name (previously source activate [env_name]).
All the required Python packages (listed in requirements.yml) are installed when creating the environment. Make sure that the new environment is active every time you run any of the Python scripts. Alternatively, linux-64 users may use environment_linux-64.yml which lists all dependencies explicitly including version and build numbers.
The steady_rotation_routine.py and dynamic_simulation.py scripts output files in the results directory that are input to compare_results.py. Therefore, these scripts should be executed prior to generating the plots that compare the simulation results of the two models. The table below lists the scripts that need to be executed to generate the figures of the paper.
| Script | Output figure(s) |
|---|---|
| turning_center.py | 5, 8 |
| steady_rotation_routine.py | 7, 12 |
| dynamic_simulation.py | 12 |
| compare_results.py | 10, 11 |
| plot_steering_input_relations.py | 13 |
| flight_trajectory_reconstruction.py | 4, A1 |
To execute one of these scripts, open the directory of the project and use the following command:
python [file_name]
in which [file_name] should be replaced by the file name of the script.
This data set is licensed under the
[1] Mark Schelbergen and Roland Schmehl (2023). Swinging Motion of a Kite with Suspended Control Unit Flying Turning Manoeuvres. Wind Energy Science Discussions, 2023, 1-32. https://doi.org/10.5194/wes-2023-121
[2] Mark Schelbergen, Roland Schmehl, Bert Buchholz, Joep Breuer and Johannes Peschel (2024). Kite power flight data acquired on 8 October 2019. Version 1. 4TU.ResearchData. dataset. https://doi.org/10.4121/19376174.v1
[3] Paul Williams (2017). Cable Modeling Approximations for Rapid Simulation. Journal of Guidance Control and Dynamics, 40:7, 1779-1788. https://doi.org/10.2514/1.G002354
[4] Mario Zanon, Sébastien Gros, Joel Andersson and Moritz Diehl (2013). Airborne Wind Energy Based on Dual Airfoils. IEEE Transactions on Control Systems Technology, 21:4, 1215-1222. https://doi.org/10.1109/TCST.2013.2257781
[5] Joel Andersson, Joris Gillis, Greg Horn, James Rawlings and Moritz Diehl (2019). CasADi: a software framework for nonlinear optimization and optimal control. Mathematical Programming Computation, 11, 1-36. https://doi.org/10.1007/s12532-018-0139-4
This project has received funding from the European Union’s Horizon 2020 research and innovation programme under the grant agreement No. 691173 (REACH) and the Marie Sklodowska-Curie grant agreement No 642682 (AWESCO).