Ride Comfort Research On The Multifunctional Harvester And Dynamical Simulation

This thesis is finished based on the State Eleventh Five-year Scientific and Technological Support Project——The Research and Explore of the Multifunctional Key Technical Equipment on the Forest Harvesting and Cultivating Operation.This thesis is also one part of the project.With the continuous development of the domestic light industry,their demand of wood is more and more big,which is not satisfied only by the domestic harvesting machinery and equipment.Though many countries already have a large number of the multifunctional harvesting machinery,there wasn't such harvesting machinery in our country.Abroad multifunctional harvesting machinery is so expensive,and they are not suit for the domestic wood production.So,the study team develops the first multifunctional harvester that is more suitable for the domestic forest harvesting operation.The development of the multifunctional harvester has certain significance to improve wood productivity and inducing labor intensity of wood workers.The multifunctional harvester is an intelligent equipment which concentrates the functions felling,delimbing,scaling,cross-cutting,and so on.When it is driving and working,it would vibration inevitably because of certain causes.So,the ride comfort model of the multifunctional harvester while driving is built in the first time.And its multi-body dynamic model is also built in the first time.Based on the model,the movement states of the multifunctional harvester are simulated on different work situation.The results provide the theory proof to the further improvement of the multifunctional harvester.The research and development status of the harvesting machinery home and abroad are in introduced.Especially the research and development status of several abroad big company harvesters is discussed.The multifunctional harvester has similar chassis to the common vehicles.So,the general situation of the recent research on the vibration system of the vehicle was summarized with the aim of providing some useful information for the research of the harvester ride comfort.The structure of the multifunctional harvester is introduced.Working operation and vibration source of the multifunctional harvester is also analyzed.Though the reasonable necessary academic simplification and reasonable condition hypothesis,five-degree-of-freedom vibration mechanical model of the multifunctional harvester is built.The excitation of the vibration model is mostly the outer vibration excitation of the multifunctional harvester. According to the built vibration mechanical model,the vibration differential equation is derived by using the second kind Lagrange equation in the first time.Based on the matrix form of the vibration differential equation,the universal solver of the five-degree-of-freedom vibration system is built in the Matlab\simulink software.Most five- degree-of-freedom vibration system can be all solved after transformed the matrix form.By the intensive input way,input all the value of the parameters to the solver program,the acceleration,velocity,displacement curve of the all model parameters are obtained by computing.Though analysis,vibration generated by ground excitation is weaken owing to the tyres and seat.But the frequency of the man-seat is in the low frequency,so the vibration reduction performance of the seat should be improved.The multi-body dynamical model of the multifunctional harvester is established in the first time by combining the Pro/E software and ADAMS using Mechanism/Pro as bridge, which exerts their advantages.In the ADAMS,the states of the multifunctional harvester is simulated when it is driving straightly,excited by triangle bump and tree stump,working too. So,the vibration state in all conditions is obtained.The tyres and seats have good vibration reduction,but the instantaneous velocity and acceleration is large.So the vibration reduction of the harvester needs to improve.The solution of the five-degree-of-freedom vibration system and simulation of the multi-body dynamical model of the multifunctional harvester prove that the vibration model and the multi-body dynamical model are reasonable.In the same time,the results supply the evidence to improve the multifunctional harvester.This thesis also offers the ways and reference to study the similar forestry machine vbirtaion.