Resource-optimized bare-metal DSP implementation of UAV flight control software

Abstract

A Flight Control System (FCS) of an autonomous Unmanned Aerial Vehicle (UAV) is highly time sensitive as it is required to efficiently integrate various sub-systems running at different speeds. Moreover, functional accuracy has to be maintained while sharing the memory, computing and peripheral resources. A real-time implementation of a complete FCS in a tight closed loop on a TI® DSP microcontroller (Delfino® Dual-Core F28377D) without kernel support is described. The bare-metal embedded code developed for this application achieves the required timing constraints through efficient use of flexible memory organization, timer interrupts and CPU resource sharing. The developed system has been functionally verified to autonomously control the intended UAV in the desired manner through extensive real-time Hardware-In-Loop (HIL) simulations. The current archetype can run at 50 Hz with extensive data logging, communication, navigation and control algorithms engaging only one DSP core.