Multibody Simulation Of Attachment And Finite Element Analysis Of Boom Of An Earthmoving Equipment

Abstract

This dissertation work describes use of multi-body simulation approach wherein computer simulations are used to predict physical behavior of earthmoving equipment under action of external forces. Excavator is taken as specific application. External forces due to hydraulic cylinders and digging force at the bucket tip are taken into consideration. The main objective of this dissertation is to determine reaction forces at different joints of attachment of earthmoving equipment under static load condition. Also dynamic model from computer simulation is used to predict reaction forces under dynamic load conditions. These reaction forces can be used as boundary conditions for doing Finite Element Analysis. Digging force is changing with different position and orientation of excavator attachment. To determine digging force Mathcad program is prepared. Multi-body simulation is carried out with MotionView software. Hypermesh is used for creating mesh and for preprocessing. Abaqus is used as solver for analysis purpose. Also optimization is carried out for minimizing weight of boom. For doing this, Hyperstudy software is used. Plate thicknesses are taken as design variables. Stress level should not exceed above 200 Mpa so constraint is imposed and the objective is to minimize weight. At last, stresses induced during dynamic load conditions are determined using ‘Flexible Body Generation’ concept.