UAV Research On Control And Communication System Based On Cotrex-M7

With the rapid development of science and technology,the research topic of UAV in military and civilian fields has caused great attention.As the "brain" of UAV,the flight control system bears variety of complex and special tasks.Since microprocessor is the core component of the flight control system which determines the control performance of the UAV.Model STM32 is the most commonly used microprocessor in current UAV on the market,however,due to its low frequency,STM32 cannot operate complex control algorithm which makes the UAV less competitive on control performance.Besides,the complexity of software system architecture causes a poorly portability for the system.The cons mentioned above will not bring great impacts for commercial UAV,but it is fatal for industrial-grade UAV.In order to develop a high performance industrial UAV flight control system,this topic will combine the advantages and disadvantages of the existing flight control system.Also,the new flight control system will be designed and implemented on top of samv71q21 microprocessor from cortex-m7 architecture serials.This topic adopts samv71q21,the latest microprocessor from ATMEL,as the core of the flight control system hardware.It was chosen not only to meet the highperformance microprocessor requirements for the flight control algorithm,but also to satisfy the performance needs of the sensor modules adopted in this topic.samv71q21 comes with up to 300 MHZ frequency,multiple data processing buses and multiple timers and other resources.It will meet various needs of data bus for different sensors,as well as the rotor expansion requirements for multi rotor UAVs.Considering the requirements of real-time performance,reliability and portability for the software platform,the Nuttx real-time operation system is adopted as the software system foundation of the flight control system which combines with existing flight control platform architecture.In order to ensure the system real-time performance,the underlying driver module of the flight control system is designed as an independent process in this case.Meanwhile,the u ORB communication system will be introduced to solve the problems of data exchange between processes,as well as the combination of wireless communication module and Mavlink communication protocol which aims at dealing communication issues between flight control system and ground station system.Regarding the explanation of flight control algorithm in this paper,the attitude and position dynamics model of the rotorcraft UAV is established based on Newtonian mechanics.At the same time,the dynamic model is simplified according to the actual flight condition of the rotor UAV.Finally,the analysis and design of attitude position controller is completed based on the simplified model and PID control algorithm,as well as the achievement for analysis and design of the horizontal position controller and altitude controller on the premise of the attitude controller stabilization.After completed the design of the whole rotor UAV flight control system,each of the modules in the flight control system has been inspected and tested independently.After that,a flight test has been done to the whole flight control system.The test data indicates that there is a great improvement on the new platform regarding the system portability,real-time and performance of the flight control algorithm,which meets the performance requirements of the industrial-grade UAV.In conclusion,the development of whole flight control system meets the expected demand.