Research On The Access Device Of The Standard Model Of Mobile Aerial Radioactivity Measurement Sample

With the rapid development of airborne radioactivity measurement and its standard model in China,the research on automatic access device of standard model has become an important factor affecting the development of airborne radioactivity measurement technology.The airborne radioactivity measurement device is equipped on the aircraft,and the relevant data needs to be tested before the aircraft takes off.The standard model has to frequently go back and forth between the storage warehouse and the airport.Moreover,in order to ensure the standard of the standard model data,the model cannot be stacked,bumped or damaged in the process of handling and transportation.Therefore,it is of great significance and engineering value to design an automatic device for standard model access.According to the actual needs of the aerial survey and remote sensing center,this subject has designed a set of automated access systems dedicated to the storage of standard models,including transportation vehicles,mechanical systems,control systems,power supply systems,and intelligent transport vehicles.This article focuses on the design and research of the access device,and the static and dynamic analysis of the access frame.The main research contents and results of the paper are as follows:First,the overall structure of the access device is designed,and the threedimensional model of the transport vehicle,the access rack,the transport rack and its auxiliary components is established and rendered using UG.The design scheme of the access rack,the working mode of the transport rack,other working parts and the working process of the entire access system are introduced in detail.The finite element analysis software is used to statically analyze the pallets of the access rack and the transportation rack,and the rationality of the designed device is verified according to the simulation results.Secondly,the modal analysis of the access rack is carried out to obtain the natural frequency of the access rack and the first six modes of vibration mode diagrams,so as to prepare for the subsequent dynamic analysis.A dynamic analysis is carried out on the impact of the transport vehicle encountering bumpy roads on the access rack during transportation.Establish a random road power spectrum model and use the Ride module of ADMAS to establish the power spectrum curve of the transport vehicle traveling on the B-level road at 60 km / h,and load the corresponding road surface excitation on the access rack using Workbench for finite element analysis and calculation.Under the action of pavement excitation,the overall deformation of the frame is smaller.The maximum equivalent stress is about 2.320 MPa and the maximum shear stress is about 0.446 MPa.The access frame will not be greatly affected by the pavement excitation.According to the analysis of the harmonic response of the access rack,the frequencydisplacement response curve shows that the frequency of the displacement peak of the access rack does not overlap with the natural frequency of the access rack,so the possibility of resonance is small.Then,the impact of the collision of the transport vehicle during transportation on the access rack is analyzed.The rigid wall is built using LS-DYNA to simulate external collisions.The dynamic characteristics after the collision showed that the acceleration of the access rack reached the maximum after 0.04 s of collision,indicating that the access rack was subjected to the largest impact at this moment.The stress at this moment is about 125.6MPa and the maximum deformation is about 0.446 mm,thus inferring that the energy in the collision process is mainly absorbed by the front wall of the transport vehicle,the bumper,etc.,and the energy transferred to the access rack is small,which has little effect on the overall structure of the access rack.Finally,the test modal analysis is performed on the access rack.Although it was impossible to complete the test due to the impact of the “Novel Coronavirus Pneumonia”,a test platform was built to explain the test equipment required in the test and briefly introduce the overall test plan.