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Abstract At present, in the process of study tour, study tutors are responsible for supervising the safety of primary and secondary schools' students, and many hidden dangers are present in safety supervision. Therefore, how to provide study tutors with intelligent information tools and thus help safety tour have become the primary issue for the construction of research bases and the normal. For this reason, this study proposes an adaptive dynamic security area generation method and dynamic security area early warning technology. By comparing the location of the dynamic security area and the dangerous area, whether the users in the area are in a safe state can be determined. On the basis of mobile smart terminals, a dynamic safety supervision system that supports the study tour of primary and secondary school students has been developed. Practical application shows that the system has perfect functions and safe, stable, and reliable performance. The system has good application prospects and promotion value and can be used in other similar field safety management and control fields.

Continuous fibre reinforced polymer (CFRP) have a distinctive anisotropic character. In traditional 3D printing processes, deposition direction cannot be adjusted. As a result, the performance of CFRP parts is deficient in the fixed direction. To address the issue, this paper proposes a variable deposition direction (VDD) 3D printing process for CFRP. The process optimises the mechanical properties of the moulded part by adjusting the direction of deposition. The principles and processes of the VDD 3D printing are described in detail. Then, using the hollow cylinder as an example, a mathematical model of the variable deposition direction structure is developed, and subsequent simulations is conducted to evaluate its mechanical properties. In the experimental part, the composite material used has a fibre content of 20% and consists of PETG and carbon fibres. The VDD hollow cylindrical parts have been printed to verify the feasibility of the process. And performance testing experiments were carried out on a variety of test specimens of different structures with VDD. The results show that adjusting the deposition direction of the CFRP can greatly improve the tensile properties of hollow cylinder. The tensile properties of a suitable structure with VDD were improved by a factor of 69.4 compared to a single deposition direction structure. And the actual tensile situation is consistent with the simulation. To summarise, the proposed method can effectively solve the defects of the traditional process and optimise the mechanical properties of the moulded parts.

The combination of the carbon fiber composite and 3D printing technology can be a powerful approach to produce the high-strength light-weight and complex construction mechanical parts. Compared with the short carbon fiber which has been widely used, application of continuous carbon fiber in 3D printing can undoubtedly better play its good mechanical properties. Usually, complex parts include multiple independent contours, which lead to discontinuous paths in the 3D printing process.For the continuity characters of the continuous carbon fiber composite, it needs to be sheared off due to the discontinuous molding printing path, so as to ensure the quality of the forming process. To solve this problem, a shearing method is put forward and the shearing device is realized. Based on the 3D printing planning path by the slicing process, the actual shearing position is calculated by shearing position recognition and distance compensation between the jump and the shearing point. On the basis of this method, the corresponding shearing device is designed to build a shearing system. The accuracy and feasibility of the continuous carbon fiber shearing system is verified by simulation analysis of path jump and single-layer and multi-layer model 3D printing experiment. The method provides basis for the realization of continuous carbon fiber composites 3D printing.