Displacement Analysis And Virtual Prototyping Research Of Grader Working Device

Grader is a kind of earthworking construction machinery, which is high-speed,high-efficiency, high-precision and multipurpose. It is widely used to form and shapethe roads, airports, farmland, etc.. With the rapid development of many industries,such as construction machinery, construction works, high-speed railway, etc., thegraders will be used in various fields more and more. The working device is the mostdirect and important stressed working part of construction machinery. At home andabroad the researches of construction machinery working devices mainly focus onfew machinery such as loaders, excavators, etc., but the direct research of gradersworking devices is rare, especially on these respects, for example, position analysis ofspatial mechanism, kinematics and dynamics simulations, optimization design ofhinged points, and also relevant data and literatures are much less. Thus this subjecthas important meanings for improving the stability, reliability and kinematicsperformance of the working device.Based on an example of a certain type of grader and the theory of spatialmechanism, according to the structural features and working ways, the hybridmechanism model of grader working device was simplified and confirmed to includea lower-mobility parallel mechanism and a combination planar mechanism. Utilizingthe numerical analysis method, an analysis has been carried out on forward solutionsof lower-mobility parallel mechanism’s displacements. Then its virtual prototype wasbuilt to make forward displacement calculation based on ADAMS software. Based onPro/E software, the3D model of the whole grader working device was established. Byintroducing the model into ADAMS simulation environment, the virtual prototypingof the working device was fulfilled. Many kinematics parameters of working devicewere analyzed and verified on the basis of four typical working ways, and the resultswere within the range error. After confirming the dynamics simulation condition ofthe working device, dynamic simulations of the virtual prototyping were fulfilled. Thecorresponding dynamic parameters along with their variation of key hinged pointswere obtained. A new model of the lower-mobility parallel mechanism was built in ADAMS, when the maximum depth of insertion was treated as optimization objective,the positions of key hinged points could be optimized. As a result a new model withreasonable structure was obtained, the kinematics performance and the reasonablenessof trajectory of the working device were improved.