Simulation Research On Virtual Prototype Modeling And Dynamic Characteristics Of Multi-systems Of Underground Load-Haul-Dump Vehicle

Underground Load-haul-dump Vehicle (LHD) is the key equipment used in underground trackless mines from 1960s. It is high efficient, maneuverable and flexible, and it has loading, hauling and dumping functions. Researches have been carried out in this study according to the problems existing in LHD design in our country. The theoretical and experimental methods in this study can solve the key problems of a complete LHD set dynamics and dynamic characteristics of system. These methods are of theoretical and practical significance for the three-dimensional and digital design of LHD. The main contents of this dissertation are as follows.1. The current developments, research trend and problems in designing and producing LHD in our country are fully and accurately summarized. At the same time, the significance of this study is expounded.2. The current developments of multi-body system dynamics and vehicle dynamics at home and outside are fully summarized, and the modeling theory and solving method of Software ADAMS were discussed.3. The kinetic mathematical model of LHD bucket system was built through adopting the kinetic theory of multi-body system. And then the velocity, acceleration and motion orbit equation of every rigid body of LHD bucket system and the motion orbit equation of the bucket tooth tip were obtained. The visual three-dimensional (3-D) digital kinetic LHD bucket system was modeled under the Solidworks software environment. By using the bucket system of model DCY-1 LHD as an example, the kinematics of 3-D bucket system of LHD with ADAMS software was simulated. And then the translational characteristics and dumping characteristics of the bucket system of LHD was simulated and analyzed.4. The dynamic mathematical model of LHD bucket system was built by means of adopting the dynamic theory of multi-body system. By using the bucket system of model DCY-1 LHD as an example, the dynamics of the 3-D bucket system of LHD with ADAMS software was simulated. The parameters affecting dynamic characteristics of LHD bucket system such as non-central loading and the action point of bucket- out force were simulated and analyzed. And then relevant conclusions were obtained respectively.5. The dynamic mathematical model of LHD was built through adopting the dynamic theory of virtual prototype. The 3-D digital dynamic modeling of LHD was modeled under the Solidworks software environment. By means of employing the model DCY-1 LHD as an example, the dynamics of 3-D LHD with ADAMS software was simulated, and then the load states of the every rigid body of LHD were obtained. The parameters affecting dynamic characteristics of LHD such as loading resistance, loading velocity and the loading distances between the bucket and the pile of ore were simulated and analyzed. And then relevant conclusions were obtained respectively.6.With theories of ANSYS software modal analysis and ADAMS software flexibility, the lift arm of LHD was translated from rigid body to flexible body, and the modal vibration types were obtained. The coupling model of rigid body and flexible body of LHD bucket system was made. The method presented in this dissertation, from finite element construction analysis in ANSYS software to dynamic analysis in ADAMS software, and then from dynamic analysis in ADAMS software to finite element construction analysis in ANSYS software, can be applied to other research fields too.7. The dynamic stresses and strain of LHD lift arm in the course of bucket out, bucket lifting and bucket dumping were simulated respectively. The dynamic stress and or strain diagrams of LHD flexible lift arm were obtained after dynamic simulation. These results laid foundation for fatigue analysis and life estimation of component.8. The simulated mathematic models were built respectively according to the analyses and researches on different kinds of steering system and braking system of LHD. The dynamic characteristics of different kinds of steering system and braking system of LHD were simulated with MATLAB/SIMULINK software. And then relevant conclusions were obtained respectively.9. In order to verify the validity of simulated mathematic model of virtual prototype of LHD, the experiments were conducted by means of employing the pneumatic-hydraulic brake system and bucket hydraulic system of model DCY-1 LHD as an example. The experimental results verify that this simulated model in this study was correct.In a word, the design theories and analyses and calculating methods proposed in this dissertation not only successfully solve the problems of LHD 3-D dynamics and system's dynamic characteristics, but also have enriched and developed the design theories of LHD. At the same time, it is of both theoretical significance and practical value to modern digital design of LHD.