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Specific to a problem of large vibro-impact aris ing from the cutting unit of the hard rock tunnel boring machine (TBM), a hybrid magnetic coupler based on soft start was proposed in this paper. The mathematical model for total eddy current losses of such a coupler was established by field-circuit method. Then, magnetic-thermal coupling simulation was performed by virtue of three-dimensional finite element software. In addition, an experimental prototype was independently designed; by comparing the model with experimental data, validity of the above mathematical model was verified. The relevant research results indicated that calculated values were consistent with experimental values, and the magneto thermal coupling method could be applied to accurately analyze temperature distribution of the hybrid magnetic coupler. By contrast to the existing magnetic coupling of the same dimension, output efficiency of the hybrid magnetic coupler was improved by 1.2%. Therefore, this research technique can provide references for designing the cutting unit of hard rock TBM with a high start impact.

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Aim to the problems of low load and precision of the serial manipulator used in casting operation. Casting execution equipment based on 2UPR-2RPU mechanism was designed. A prototype of heavy-duty casting robot has been proposed and developed. Based on the theory of robot topology, the mechanism constraint relation of the casting execution equipment was analyzed, and it is concluded that the casting actuator has three degrees of freedom. Both the inverse position equation of the casting execution equipment and axial velocity equation of branch chain were established. In this article, kinematics simulation of the casting execution equipment based on ADAMS software was presented, and its kinematics characteristics of each parallel branch chain were analyzed. The validity of this kinematics model of casting actuator was verified. Based on the working space analysis method for parallel mechanism, the working space range of casting execution equipment was simulated by the MATLAB software. This research provides a reference for expanding the application of hybrid structural robot in casting field and developing casting heavy-duty casting robotic products.

In order to release the lateral force of pipe conveyor belt in vertical transportation, the thesis had a study of the lateral force of the conveyor belt. By making use of Janssen Principles and fractal theory, based on reasonable simplification, the author established a mathematical model of the lateral force in vertical transportation, and with the research foundation of the pipe belt conveyor for underground transportation, through solution analysis, the author found out that the change of material diameter would lead to nonlinear variation of the lateral force of the conveyor belt. Under the circumstances of different material diameter, discrete element method was adopted to simulate the lateral force of the conveyor belt, thus working out the distribution curve chart of the lateral force. To verify the reliability of the theory, the author built an experimental platform for pipe conveyor belt in vertical transportation, and experimented with five groups of materials in different diameter, working out the strain of lateral force of the characteristic conveyor belt; by comparing the theoretical result, the simulation result and the experimental result, it showed that the solution to relieving lateral force through optimization selection of material diameter put forward in this thesis was reasonable and effective. It provides theoretical reference for the design of pipe belt conveyor.