My thesis discusses my contribution to the FLEXOP project that I participated in at MTA-SZTAKI, which was designing and developing a suitable flight control computer specifically for the experimental UAV being built exclusively for the purposes of this project.
FLEXOP proposes active control over the aircraft's actuators inside the flexible wings to possibly counteract the negative effects of aeroelastic flutter. In theory, this could be achieved by measuring the local inertia of the wing segments, and acting upon these measurements. Theoretical possibilities notwithstanding, any such unmanned aircraft would need an avionics system, therefore based on the demands of this project, requirements were laid down regarding a flight control computer.
From our preliminary research on the market, we concluded that none of the readily available popular FCCs would suffice for handling both the baseline flight control tasks and the flutter-related specific demands of this project, therefore we resorted to design our own system from the ground up.
In the beginning of this process, we specified the details of our flight control computer. In this, we devised a system consisting of the following elements: a single board computer as a processing unit, to broaden its capabilities regarding external connections; an I/O extender and, for a safety measure, a radio control multiplexer which, provided that the human pilot intervenes, could possibly prevent a crash in the event of a critical system failure.
To materialize this conceptual system, consisting of multiple boards, I chose the specific parts in accordance with our requirements, this involved power supply design and microcontroller interfacing with numerous protocols. Following this, I implemented schematics to accommodate these components. Based on these schematics, I designed the printed circuit board layouts of our boards with care regarding high-speed, ESD, and EMC considerations. After we got our PCBs manufactured, I populated these boards with components, and tested them to great extent.
Over the course of my thesis, an UAV FCC platform, specially tailored for the FLEXOP project's demands and requirements was designed and prototyped. However, this platform could be made to fit other applications easily, even if through a redesign. In theory (and hopefully in practice), our part of the experimental aircraft's avionics system does not contain any single point, whose failure could compromise the safety of the airframe by itself, provided that the human pilot intervenes in the event of any such failure.
Finalizing my thesis I will outline some of the opportunities regarding future improvements of our system, enabling further development.