Research On Dynamics Simulation Of Crawler Travelling Mechanics Of Large Mining Excavator

Working in the open-pit mining,Excavator is the main equipment,it has a high degree of mechanization and automation,environmental performance, mining high efficiency,faster progress,reliable,good mobility and so on.Crawler sector is a major component of excavators.Crawler bear the pressures and torque,bear to face directly the torque in the process of excavators'working. Crawler also undertake the task of walking.For a large excavator,crawler-type is the best change,because the crawler can bear more load,few compression ratio.The analysis for crawler with the kind of experiment to come to the conclusion not only waste lots of time,also waste lots of manpower and resources,leading to increased costs,the longer development cycle,few profits and the competitiveness of their products in the market will be greatly decreased.Therefore,it is necessary for virtual prototype simulation in the computer to create a virtual environment for the work of the crawler.In this virtual environment for simulation and analysis agencies crawler.Such a greatly development costs will be reduced,the development cycle will be shorten.Meanwhile,the competitiveness of the products in the market will be improved significantly.In this paper a theoretical analysis of the whole crawler structure and some elements determine the type and the relationship of the components.Based on analysis the virtual prototype simulation,some results are concluded.Having numerous components organizations,sports complex,dynamic model in establishing is necessary to impose a correct and strict constraints.In the process of the constraints imposed,a good relations between the components of movement and freedom should be analyzed.To prevent over-constraint,the revolvable sections of each plate and the cylindrical section of the last track should be paid attention to.In the process of the establishment of a crawler kinetic model,the most complex contact force is imposed.Several contact forces are acting between driving wheel and track boards,guidance wheel and track boards,supporting wheel and track boards in walking.There are 912 contact forces in the kinetic model.It is not accurate and realized to impose the numerous contact forces with the usual method.The best selection is the macro in ADAMS.It's very convenient to impose numerous contacts with the cycle syntax of the macro.In the paper,the"for"cycle syntax of the macro is used frequently.The simulation analysis for crawler is divided into two parts:the way forward and backwards.Excavator at work will inevitably retreat.Tracked by the system backward is a great distinction with forward.The inner resistance of the walking system become greater in backward.Through this simulation shows the walking situation of the driving wheel in advance and retreat.For analyzing the relationship between the convex surfaces of the driving wheel and tracks,two tracks are selected in forward and backward.Four coincidence points are installed on the coincidence surface of the driving wheel'convex and tracks'convex.Four theory coincidence points were discussed in the actual operation about the movement of relative displacement,the relative acceleration and relative velocity.It was studied that the tracks is meshing with the driving wheel preliminarily.To provide a basis for analysis of wear their engagement,the sliding situation of the meshing surface was concluded.In the paper,UG and ADAMS were used to create a crawler 3D model and run dynamic/kinematic simulation analysis.In practical work,the results obtained with this method can improve the efficiency of product development,shorten the product design cycle,improve product quality and reliability,which can have significant economic benefits.