Dynamic Analyses And Controller Design For A New-Type Face-Shovel Excavator

In recent years, as everyone knows of the rapid development of national economy. As the quantity and investment of projects of the public port infrastructure, water and hydropower as well as ore mining, increase quickly and the scale is gradually huge, the need for large loading and mining equipment grows rapidly. Due to advantages of high load-carrying capacity, great efficiency and wide workspace of face-shove hydraulic excavators, more and more users select face-shove hydraulic excavators for mining and loading. However, there are much less systematical design and analysis researches in China. In addition that the foreign intellectual property chronically monopolize, as well as the type is unitary. Based on these, this thesis proposed a new-type multi-linkage mechanism which is suitable for face-shovel hydraulic excavator from the point of mechanism innovation, furthermore accomplished the whole analyses of performance characteristics and design of controller.The article followed the studying process of selection of mechanism, analysis of kinematics, analysis of dynamics, simulation of virtual prototype and design of controller. Based on the atlas database of planar 12-link 3-DOF topological graph, moreover according to several additional selection principles, which were established by the operating characteristics of face-shovel hydraulic excavators, then a suitable mechanism was elected.According to the loop algebra theory and the graphical modularization, a universal analysis flow diagram of mechanical kinematics was established. The mathematic models of kinematics were built, as well as the position kinematics solutions, velocity solutions, workspaces and three sets of mapping relationships of state space were conducted. By contrastive simulation experiments, the correctness of kinematics analyses was verified. The generalized moments of joints effected by components were obtained, based on the Kane method and principle of conservation of energy. According to the equivalent principles, the relationships between the driving forces and joint torques were established. Eventually, the dynamics mathematical models were deduced and built.The virtual prototype model of the face-shove hydraulic excavator was built based on Solid Works and ADAMS. The simulation analysis and verification of dynamics characteristics were conducted in ADAMS software, which were compared with the results simulated by MATLAB. Then the correctness of the dynamic mathematic model was testified. With the control system of boom hydraulic cylinders, for example, the transfer functions of three sets of hydraulic cylinders were built. Before adding the controllers, the control system was steady. However, the error of tracking was great, and the phase delayed. The system could not track control parameters in a short time. After adding the PID controller, the control system was steady. In addition, the response time and the adjust time were reduced, and the target tracking effect was good. The results show that the controller basically met the actual control requirements.