PyFDM: A modular flight dynamics simulation environment for fixed-wing aircraft with morphing wings

Kurzfassung

The Python Flight Dynamics Module (PyFDM) is a flight dynamics simulation environment designed specifically for the requirements of highly actuated, morphing wings. Classical approaches to modelling the aerodynamics, for instance those based on look-up tables or on linear aerodynamic derivatives, become impractical for systems with pronounced fluid-structure coupling and a large number of control variables. The development and evaluation of modern control methods therefore calls for a continuous \enquote{live} re-computation of aerodynamic forces and moments. PyFDM addresses this challenge through a modular and flexibly extensible design. The simulation environment reproduces the complete six-degree-of-freedom flight dynamics and integrates models for actuators, sensors and atmospheric disturbances such as turbulence. Several modelling approaches are available for the aerodynamics, among them derivative models, surrogate models and methods based on the vortex lattice method (VLM). Depending on the application, a suitable compromise between model fidelity and complexity can thus be selected. A central development goal is ease of use: The environment is intended to be usable by flight control engineers without specialised software engineering training. At the same time, the modular design permits a flexible adaptation of the simulation environment to different aircraft systems and research questions. PyFDM supports several numerical solvers and offers interfaces to established communication protocols such as MAVLink. Beyond this, the integration of Functional Mock-up Units (FMU) allows externally developed flight control laws to be embedded in the simulation. External tools can be connected for visualisation. In addition, PyFDM is integrated into the Gymnasium environment and therefore permits direct use for the training of reinforcement learning agents.