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Aiming at the weak stiffness of the series support mechanism of the partial-face boring machine, poor adaptability of the non-circular TBM section, and difficulties in dealing with the blind area of excavation, a partial-face TBM propulsion mechanism based on the 6-SPS parallel mechanism is designed, and a stiffness prediction model establishment method considering the local flexibility of the platform is proposed. Firstly, the geological conditions is selected, the propulsion reaction force is calculated according to the total thrust prediction model, and the propulsion mechanism is designed. On the basis of inverse kinematics; the rectangular coordinate boundary search method is used to calculate the position workspace of the mechanism. Then, by deriving the micro-displacement mapping between branch chain and the platform, the branch chain is considered, the gravity of the moving platform is regarded as an external load, and the finite element software is used to identify the flexibility coefficient at the contact point between the platform and the branch chain; a semi-analytical static stiffness model of the propulsion mechanism is established, which is verified by the finite element software. Finally, the influence of the local flexibility of the platform on the stiffness performance is compared and analyzed, and the results show that the stiffness model considering the local flexibility of the platform is more accurate. This study provides a theoretical basis for the design and development of the partial-face TBM propulsion mechanism.

To eliminate blind spots in the field of vision and achieve a safe and collision‐free path, this paper proposes a path planning method based on multivehicle collaborative mapping in the context of vehicle networking. First, a multi vehicle map merging strategy based on the fireworks algorithm is proposed. In this strategy, a dissimilarity objective function based on the concept of grid map similarity is established and an improved fireworks algorithm is used to quickly search for the maximum overlap between local maps, achieving multivehicle collaborative mapping. Second, a real‐time path planning method based on artificial potential field theory is proposed. The information obtained from multivehicle collaborative mapping is first combined with the potential field model to form a multifield coupled road environment model. Then, the obstacle repulsion potential field model is improved to address the issues of traditional artificial potential field methods that target unreachability and poor dynamic response. The feasibility and effectiveness of the collaborative path planning method and single vehicle path planning method are tested through simulation analysis. This paper demonstrates through simulation analysis that the proposed path planning method can effectively achieve beyond line of sight perception and safely and comfortably guide vehicles to complete path planning. [ABSTRACT FROM AUTHOR]

[Display omitted] • A multi-objective optimization framework of operation parameters for large vertical mills is developed. • A numerical calculation method based on DPM-CFD of particle–fluid coupling system in large vertical mill is designed. • The Kriging method was used for correlation analysis, and the NSGA-II algorithm was used to obtain optimization results. The association mechanism between the main operation parameters and multi-physical fields of the large-scale vertical mill system is unclear, which leads to the difficulty in optimizing operation parameters to improve the performance of large vertical mill systems. To investigate the mechanism of multi-physical field coupling in the operation of the large vertical mill, the numerical simulation method is constructed by coupled CFD-DPM model to calculate the finished product quality, the simulation results were in good agreement with the actual operation results. Based on the Kriging surrogate model, a multi-objective optimization framework for large vertical mills is proposed. Finally, the multi-objective optimization design of LGM large vertical mills is carried out. Combined with CFD-DPM coupling method is developed, design variables and output responses are determined. The Kriging method is used for correlation analysis. The multi-objective optimization function was established. The NSGA-II. optimization algorithm was used to update the surrogate model and obtain the optimal solution, and the optimized operating parameters increased the vertical mill yield by 5.34% and the specific surface area by 9.07%. The maximum relative error between the simulated value and the optimized value is 2.02% through numerical calculation, which verifies the superiority of the optimization method of large vertical mill for performance improvement. [ABSTRACT FROM AUTHOR]