Integration for a nonlinear quadcopter with flapping dynamics model into Mission Planner and Flightgear for 3D visualization

The objective for this milestone was to integrate the same model functionality developed and analyzed within the Matlab/Simulink environment into a mature environment that will be able to test most functionalities of the Flight controller software that will be flashed for real-flight testing.

The decision was to either migrate the Ardupilot (in this case ArduCopter) software into the Matlab environment or integrate the highly nonlinear quadcopter model with flapping dynamics into the Ardupilot environment. The former option would mean no easy integration with Mission Planner and the real-time sofware-in-the-loop (SITL) testing tool (which also includes the infrastructure to communicate with the Flightgear 3D visualization environemt, while the later with make use of singular environment although the software development effort would quite tedious and error-prone.

It was chosen to go with the first option as this was thought to be lead to more mature verification method prior to real-flight testing while having a relatively smaller integration effort. This effort was also also aided with the fact the simulation model in MATLAB was already designed in source code format (C++) and then wrapped around in MEX (Matlab Executable) which was compatible with the Ardupilot C++ environment.

The integration of the quadcopter model was done in a phased approach testing the robustness and functionality of the simulation after each integration step. This resulted in a considerable amount of debugging time saved allowing the whole integration to be completed within a week.

The Flightgear program was configured to use this new airframe model and this successfully tested using the Mission Planner software the Ground Control Station. The results from this milestone has enabled the analysis of aerodynamics effects to be quantified both on subsystem level using MATLAB, system level (using Mission Planner) and visualization (using Flightgear). This now serves a in depth analysis tool to the performance of subsequent designs that will be developed in the near future.

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