Research On Lightweight Design And Molding Technology Of Unmanned Aerial Vehicle

In today's world,the development of Unmanned Aerial Vehicle(UAV)is changing with each passing day,and the long endurance time and far reconnaissance distance is one of UAV's development directions.The endurance time of foreign unmanned reconnaissance aircraft is up to 40 hours or more,and the maximum detection radius is up to 300 km,which make it can perform the reconnaissance missions for a long time in standoff.In order to make the radar see farther and more clearly,the large size radar becomes one of the necessary load equipment.But the endurance time of UAV is directly affected by the weight of radar,and the endurance time affect the combat capability further.The research of this thesis relies on the engineering development of an unmanned airborne radar.According to the requirements of overall scheme,the lightweight design and the molding technology of radar structure were studied,which based on the previous experience in the development of radar.The requirement on the device's weight limit is implemented.And the manufacture and the test verification of the radar machine have been done.According to the requirements about the function,weight and volume of radar,conventional materials can not meet the needs of the lightweight design for radar.So the special composite material was selected as the radar structural material.Through the study of various characteristics of the composite materials,E glass Fiber,Quartz glass fiber and Aramid fiber III were chosen as the alternative materials for structural design.Various mechanical properties and electrical performance index of the three kinds of materials were comparatively analyzed,and the Aramid fiber III was preliminarily selected as the main material for the lightweight design of the unmanned airborne radar structure finally.Because of the structure and function composition and the weight distribution of unmanned airborne radar,a plan which focus on the lightweight design of the servo frame on the radar's front combination was established with the lightweight design of the terminal combination in support.Aramid fiber III was used to manufactured the servo frame.We used the combination structural form of the truss and reinforcing bar to design the radar.UG was used to establish the radar's three-dimensional(3D)model and the weight was proved to meet the requirement by the simulation test.Through the simplification of the 3D model,the finite element simulation of radar structure by the ANSYS software was carried out.The rigidity and intensity of servo frame structure with composite material were proved to meet the requirements though the analysis of the simulation result of stress,modal and displacement.According to the comparative study of the various processing and molding technology,we mastered a set of molding processing technology about the aramid fiber III composites,and completed the production and manufacture of the whole radar finally.The impact test and the vibration test of the physical machine of the unmanned airborne radar were completed.The related mechanical properties were proved to meet the requirements of the structural design.Eventually,through the research of this thesis,the weight of radar with composites was 18 kg lighter than the metal materials.The lightweight structural design and the molding manufacture of an unmanned airborne radar was completed,which accumulated many experiences for the future application of composite materials in radar structure.