Research And Implementation Of Multi Flight Modes Control System For Small Size Unmanned Helicopters

The research of small-scale unmanned aerial vehicle (UAV) helicopters gradually becomes more and more popular both in industrial and academic filed in recent years. The small-scale UAV helicopters are agile, controllable and can take-off and land vertically, hover, and cruise. Owing to these natural advantages, they are widely used in military and civil domains.The main purpose of this paper is to develop an autonomous flight control method for small-scale unmanned helicopter. In this paper, flight control algorithms base on PID are designed, and a large number of simulation and real flight experiments were made to verify the proposed flight control methods. The main contributions of this paper are outlined as follows:(1) The Mathematic model of small-scale unmanned helicopter was researched. Based on the dynamic model proposed by researchers from Carnegie Mellon University, we understand the characteristics of our own TREX 600 helicopter.(2) Based on the classic PID (Proportional-Integral-Derivative) method, autonomous flight control system was designed: A flight control system using the classic PID method is developed. The whole control system is separated into three loops. Simulation results show that with this control strategy, the UAV helicopter can autonomously take-off, landing, and hovering.(3) Based on Multi-modal in helicopter flight, the helicopter modal can be divided into five modals: static modal, take-off modal, cruise modal, landing modal and fault modal. In every flight modal, we designed different control strategy for make flight control system complete flight tasks better. (4) According to the characters of airborne software, the method of software architecture is researched. The logical view and data view are given to the flight control system to make sure the architecture is well capability.(5) The flight control system air-borne software was designed and developed in an onboard computer PC 104, with Linux operating system.(6) Perform real outdoor flight experiments: The real outdoor flight experiments show that the autonomous flight control system proposed in this paper is correct and effective.The achievement of this paper is provides a vital foundation for the research and application on the small-scale unmanned helicopter. The flight control system be proposed in this paper can successfully drive TREX 600 helicopter to take-off, landing, and hovering outdoor, with excellent performance in control precision, stability, and response time.