Prescribed-Time Fault Tolerant Control Of Quadrotor UAV And Its Application

With the rapid development of information technology such as computers and wireless communications,unmanned systems are developing towards greater intelligence,efficiency and safety.Unmanned systems have become an important direction for future development,and they will bring significant changes and innovations to many fields.Unmanned systems are gradually replacing humans as the mainstay in scenarios with difficult and dangerous environments and in some repetitive activities,such as automated robotic arms in factories;automatically guided AGV vehicles in ports and warehouses;and quadcopter UAVs for automatic inspection of electrical facilities.Unmanned systems are changing the way these industries produce and improving productivity.Quadcopter UAVs are typical of these unmanned systems.In today’s society,the rapid development of quadcopter drone technology is changing the way people live.With its flexibility,portability and mobility,quadcopter UAVs are widely used in aerial photography,agriculture,logistics and other fields.However,as application scenarios continue to expand and become more complex,the requirements for flight control of quadcopter UAVs are also increasing.How to achieve more stable,accurate and efficient control,and even how to continue to fly and land safely and smoothly after a malfunction,has become an important issue in the field of quadrotor UAV research.Therefore,this paper is closely focused on the above-mentioned issues,and the main innovations and contributions are as follows:(1)In response to the problem of motor failure failures occurring during the flight of a quadrotor UAV,a quadrotor UAV system model considering the motor failure situation is first derived based on the ideal model of a quadrotor UAV.According to this model,a quadrotor UAV fault observer is designed,through which the fault information is estimated to improve the flight safety of the quadrotor UAV.(2)For quadrotor UAS convergence times that need to be more precise.In the attitude system,a quadrotor UAV prescribed-time attitude controller is designed using the backstepping design method to realise that the attitude and angular velocity information of the system can reach the desired state within a pre-set time regardless of the initial state;in the position system,a prescribed-time position controller is designed to realise that the position information and velocity information of the quadrotor UAV can reach the desired state within a pre-set time.The virtual control volume is also introduced,and the designed attitude controller and position controller are coupled together in the form of an inner and outer loop to realise the control of the complete process of the quadrotor UAV.(3)To address the problem that the factors encountered in the real environment are far more complex than those considered in the theoretical simulation,there are certain risks if the theoretical research results are directly applied to a real quadrotor UAV,so a quadrotor UAV hardware-in-theloop simulation platform is designed and built in this paper.This platform enables the rapid deployment of novel control algorithms into real-world environments,while reducing the risk and cost of research.The proposed quadrotor UAV fault observer and pre-determined time attitude controller are deployed into the platform in this paper to verify their effectiveness in real systems.The rapid development and widespread application of quadrotor UAV technology requires continuous research and exploration,and the results of this paper provide useful references and lessons for technological research and application in the field of quadrotor UAVs.