Study On Flight Control System Of Small Unmanned Helicopter

Unmanned helicopter has an extensive application in both military and civil domain. This dissertation focuses on building an autonomous flight control system on a small unmanned helicopter. The flight control system architecture is designed. The flight control law design based on hover mode of helicopter are accomplished and the reliability of the integral system is validated through the actual experimental flights.According to the overall system design requirements, the devices for hardware architecture of the control system are selected and the overall architecture of flight control system is built. In this dissertation, based on the analysis of the dynamic model of the small helicopter, the attitude controller and velocity closed-loop controller for hover mode are designed. Then the hierarchical hybrid control system is built in accordance with the multi-mode characteristic of unmanned helicopter and the full envelope flight task. The result of the rectangle cruise flight in 3-dimension space on the small helicopter validates the control algorithm.The main work of this dissertation is as follows:(1)The overall framework of the flight control system for a small unmanned helicopter is established. The system satisfied the technical indexes and the function requirements, which has the explicit definition of the subsystem, good planning interface, and rational portability and expansibility.(2)The dynamic characteristic of the unmanned helicopter is analyzed and its approximate linearization model in hover mode is built. Based on the model the attitude controller and the velocity controller of unmanned helicopter are designed. Both the hovering experiments and the small speed forward flying experiments have achieved good application effect.(3)The hierarchical hybrid system framework is built to complete the rectangle cruise flight task in 3-dimension space on an unmanned helicopter. This experiment solves the most common problems in the implementation process of building the flight control system, which provides theoretical basis and rich practical experience.