Mechanics Property Analysis And Optimization Research Of Hydraulic Heavy Mechanical Arm

The hydraulic heavy mechanical arm is an important auxiliary equipment in mining machinery.The force of the manipulator is complicated during the process of replacing the liner of the mill.Its strength,stiffness and vibration characteristics are related to the safety and stability of the whole manipulator in the process of transportation and assembly,and the good operation of the manipulator cannot be ignored.By taking into account the policies issued in China,such as smart manufacture and so on,the finite element technology is adopted to carry out the exploration on the structure of the manipulator,to understand the redundant parts and optimization space of the research and design,is of great significance to the verification and industrialization of the hydraulic heavy mechanical arm.The specific research content is as follows:(1)In line with the demands of the work,it carries out research on 11 working conditions.Based on this,the hydraulic heavy mechanical arm’s normal operation needs 3 necessary conditions.When it comes to the models of the hydraulic heavy mechanical arm under the typical working conditions,Solid Works and ANSYS Workbench contain it.The mechanical arm was meshed by the Partition Grid Division Method based on the model’s perfection,the high quality mesh was obtained.What’s more,it conducts exploration on the pressure and deformation under the working environment that was typical.As a result,it can get clear of the most dangerous points existing in those three conditions.(2)Based on the analysis of the vibration characteristics of the working environment with danger,the frequencies in normal states and the modes of the first 6order of the hydraulic heavy mechanical arm that corresponds with it were obtained by modal analysis.According to the analysis related to harmonic response analysis,the transformation curve of the hydraulic heavy mechanical arm with frequency was obtained,and the amplitude of the hydraulic heavy mechanical arm is almost the same as the frequency of response.As for the vibration amplitude,it can reach 31.55 mm at5.40 Hz to the largest extent.Comparing the two analytical methods,it can be seen that the amplitude’s response frequency at the maximum status of the mechanical arm gets close in contrast with the frequency of the two orders.Leading to the difficulty in exciting the hydraulic heavy mechanical arm under the first and second order modes.(3)Box-Behnken is referred to in this thesis,which focus on the use of Design Expert to carry out the research on the three-factor and three-level telescopic arm.Their 3D models were established according to 13 groups of sample parameters combination.In addition,it makes the research on the finite element simulation.Through the application of cross-term quadratic polynomial,the response surface function is built in this thesis.In terms of the conduction of the regression analysis,each parameter’s connection with the response surface is studied by using the way of the least square.On the other hand,it gets the section’s optimal parameter combination,in which it reduces 65.10 kg for the telescopic arm.(4)For the purpose of verifying the optimization scheme’s accuracy,ADAMS/View Flex module was used to carry out flexible processing of key components.By adding the constraint relation between each part,and setting the motion law,it makes the rigid and flexible coupling simulation that is related to the hydraulic heavy mechanical arm models experiencing optimization through the adoption of the step function.After that,the motion track is obtained.The significant reduction of the vibration change of the optimized end-effector is reflected from the simulation results after conducting the contrast.Through referring to the trajectory error,it gets the result that the average value of the total trajectory error is reduced by 1.61 mm after calculation.