Design And Research On Retracting And Putting Down Automatically System For UAV Landing Cear

Retracting and putting down automatically of UAV landing gear is an important basis for large-scale UAV to complete taking-off and landing.At present,most of UAV landing gear retractable systems use the hydraulic actuation structure,and hydraulic retractable system has some advantages,such as mature technology,the output power,dynamic response,positioning accuracy.However,due to the use of hydraulic retractable system UAV fuselage covered with long hydraulic lines,it can easily lead to leakage,and there are some issues,such as complex system has the advantages of simple structure,easy maintenance,high efficiency and high reliability.Therefore,it is of great theoretical and practical importance to carry out the research of the electromechanical actuation system of UAV landing gear.In this dissertation,we thoroughly study the UAV landing gear actuation system,and emphasize the research work on the design of the UAV landing gear electromechanical actuation system overall structure,the research work on the design of the UAV landing gear electromechanical actuation controller,multi-motor real-time multi-task control technology research.The main research contents are summarized as follows:(1)We systematically analyze the functions and the compositions of the electromechanical actuation system of the UAV landing gear,and put forward overall structure of UAV landing gear electromechanical actuation system.The main redundancy uses multi-motor control center based on DSP and FPGA architecture,which achieve the speed and current dual closed-loop control.The backup redundancy uses pure hardware logic circuit,which achieve open-loop control at a fixed speed.(2)According to the overall structure of the UAV landing gear electromechanical actuation system,the software and hardware structure design and principle prototype of the electromechanical actuation control system of the landing gear are completed.The design of hardware circuits include the design of main control circuit unit,the design of main drive circuit unit,the design of backup drive circuit unit,the design of rotor position,speeddetection circuit unit,hall signal processing circuit unit and power supply circuit unit.The software design includes DSP programming and FPGA programming.(3)The simulation model of UAV landing gear motor system is built in Simplorer environment.The simulation model includes motor ontology model,drive controller model and load model.The traditional PI control algorithm is used in the velocity loop and current loop to verify the effectiveness of the double closed-loop control structure.(4)The experimental platform of UAV landing gear electromechanical actuation system is built,and the experimental verification is done when main redundancy and backup redundancy work.