| The development trend of the excavator is high efficiency, energy saving and intelligent. The excavator industry in our country has no market competitiveness for its long development period and high cost of the new products. The excavator products in our country are far from the need of the development trend. The development of virtual prototyping provides nice method solving those problems mentioned above. It is studied in this paper that applying virtual prototyping in the excavator intelligentizing, supported by the China National Hi-tech R&D Program (863 Program) Study on the key technologies of the integration and intelligence of non-structure environment mobile robot (Granted No.2001AA422130) and national science foundation Generalized optimal mechanical design theory, method, technology, realization and application (Granted No. 59635150). The main points of this dissertation are building a virtual robotic excavator model integrating different subsystems, which is used for the analysis and optimization of the excavator energy saving and intelligetizing technology, improving the efficiency and automation of the excavator.1. The strategy of realizing the virtual robotic excavator prototype is put forward, taking the integrated mechanic hybrid property of the robotic excavator into account. The robotic excavator is separated into three related subsystems according to the need of abstract modeling, which are mechanical system, hydraulic system, control system. In order to get a comprehensive performance simulation platform, the integrated modeling of mechanical, hydraulic and control systems is developed. It mainly involves modeling of the subsystems and model integration trough parameter correlation, data interface setting up, integrating the subsystem models together in the software ADAMS. The dynamic, hydraulic and control system simulations can be analyzed on the resulted virtual performance test-bed of the robotic excavator2. In order to analyze the kinematics and dynamics of the robotic excavator, the modeling of the mechanical and dynamic systems is studied. The theoretical kinematic and dynamic models are induces through the method of D-H and Newton-Euler separately. Based on the research above, the simulation model of the robotic excavator mechanics is developed in the software ADAMS, which can be used to analyze the dynamics visually.3. The hydraulic and control system models are studied and developed in ADAMS. During the traditional modeling of the excavator hydraulic system, in the equations of the hydraulic actuator motions, the mass of the piston and piston rod and the external load are assumed constant for the they are related to the dynamic model and hard to exactly measured, which causes the discrepancy between the simulation model and the physical model. Modeling the hydraulic system based on the dynamic resolving of the virtual prototype is put forward to solve the problem mentioned above. Through modeling the hydraulic system in ADAMS and integrating the hydraulic model and the dynamic model through parameter correlation, the mass and external load will vary with the moving of the excavator through the automatic dynamic solving function of the ADAMS, which makes the simulation model simulate the hydraulic system performance during the real duty time more exactly. Then based on the modeling of the hydraulic system, the powering saving and servo control systems are modeled and integrated with hydraulic models by parameter correlation.4. Research on the evaluation of the digital virtual prototype accuracy. The author designed lots of tests to verify the accuracy of the model qualitatively and quantitatively. The qualitative validation is finished by checking whether the simulation results are inconsistent with the basic...
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