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In order to reduce the measurement time of blade in the machining process, a data reduction algorithm is proposed in this paper. The proposed algorithm first selects a set of starting points on section curves. And then change-points are found according to its tangent properties for different segments divided by the starting points. In each segment redivided by the change-points, a redefined criterion uses a variable distance between the approximating line and section curve as objective function to ensure the proposed algorithm reserves more points where the curvature of the curve is large. This makes the achieved polygon accurately retains both the shape and details of section curves. When compared with other polygonal approximation algorithms, the proposed algorithm gives consideration to both computation time and compression rate, obtains a better approximation error distribution. Experimental results show that the proposed algorithm is stable and useful in actual machining process.

The blade is one of the key part of aero engine because its shape precision and surface quality significantly influence the performance, efficiency and reliability of the engine. The blade surface is generally obtained by precision finishing process, which is a repeated work of profile error measurement, profile error calculation and error correction manufacturing. For profile error calculation, the matching of measurement points and ideal blade surface must be firstly performed. However there is few detailed work reported on matching algorithm. In this paper, a new matching algorithm for profile error calculation was proposed. Firstly, the coarse matching method based on characteristics of blade section curves between measurement points and its corresponding ideal section curve was studied. Then the Sigular Value Decomposition (SVD)-Iterative Closest Point (ICP) precision matching method was adopted to improve the matching precision. After that, the weight calculation method was applied to balance the profile errors among different section curves. Simulation work was performed to validate the proposed matching algorithm. Results shows that micrometer-order matching accuracy of the blade section curves could be obtained through the above-mentioned three matching steps.

At present, when 3D printers print large angle surfaces, hollow and cantilever structures, printing materials are affected by gravity factors, photosensitive resins or special materials need to be added as support. To save material, increase stability, solve the problem of filling several supporting structure and so on, we optimize the structure of 3D printer. We design a platform flip 3D printer and introduces its structure and working principle to establish the simulation model of the system. The new structure is analyzed and the feasibility of the new 3D printer structure is proved finally.

In order to improve the dynamic performance of the grinding machine and improve the machining precision of the machine tool, a modal experiment is conducted on the complete machine and main sub-structures of the series-parallel hybrid grinding and polishing machine tool according to the basic theory of experimental modal analysis. Also, hammer impulse excitation and varied-time-based sampling methods are adopted to perform experimental modal analysis. Meanwhile, the eigensystem realization algorithm (ERA) is utilized to identify modal parameters, so that the low-order natural frequency, damping ratio and modal shape of the complete machine and its main substructures can be obtained. Based on the analysis of frequency and vibration mode, the beam is a weak link of the machine tool, while an approach to improve the dynamic characteristics of the machine tool structure is proposed to provide a basis for the optimized design of dynamics.

Blade is the key component in the energy power equipment of turbine, aircraft engines and so on. Research on the process and equipment for blade finishing becomes one of important and difficult points. The motion control of hybrid grinding and polishing machine tool is different from that of traditional machine tool, and there exists motion coupling phenomenon when it moves as a whole. In order to control precisely motion of machine tool, the inverse and forward kinematics solution considering motion coupling of parallel mechanism was solved based on designed hybrid grinding and polishing machine tool for blade finishing in this paper. Firstly, the coupling factor of parallel mechanism was taken into account in the new model, and the inverse kinematics solution was modified to improve the solution accuracy. Then, the forward kinematics solution of machine tool based on inverse kinematics solution was solved. Finally, the motion simulation was made to verify the inverse and forward kinematics algorithm based on kinematic coupling factor of parallel mechanism by simulation software ADAMS. The simulation result shows that the inverse and forward kinematics solution deduced is correct, which provides theoretical basis for the motion control scheme of machine tool calibration and inspection control system.

Mandible defect and the lack of dentition may result in facial deformity and chewing organ defects. It happens after the surgery of oral and maxillofacial tumors. This study aims at this problem. In this study, Finite Element Analysis (FEA) was employed to reconstruct the implanted mandible for customized patient. The 3D FEA model has great importance for biomechanical analysis. Though the analysis of the biomechanical situation with different numbers of dental implants, we can optimize the location and quantity of the implants. In this way, we can improve the quality of the implants, reduce the pain of patients, reduce the operation cost and avoid secondary surgery.

Blade is the key component in the energy power equipment of turbine, aircraft engines and so on. Researches on the process and equipment for blade finishing become one of important and difficult point. To control precisely tool system of developed hybrid grinding and polishing machine tool for blade finishing, the tool system with changeable wheel for belt polishing is analyzed in this paper. Firstly, the belt length and wrap angle of each wheel in different position of tension wheel swing angle in the process of changing wheel is analyzed. The reasonable belt length is calculated by using MATLAB, and relationships between wrap angle of each wheel and cylinder expansion amount of contact wheel are obtained. Then, the control system for changeable wheel tool structure is developed. Lastly, the surface roughness of blade finishing is verified by experiments. Theoretical analysis and experimental results show that reasonable belt length and wheel wrap angle can be obtained by proposed analysis method, the changeable wheel tool system can be controlled precisely, and the surface roughness of blade after grinding meets the design requirements.

Aiming at the implanted mandible titanium plate in chewing movement under the action of repeated load is prone to fracture, leading to problems such as secondary surgery. This study makes fatigue simulation analysis for customized implanted titanium plate of fatigue damage. It also analyzes the minimum service life position and low service life area on different loading. Simulation analysis of deformation is done. The analysis contains the deformation area and the maximum deformation degree with a variety of bite condition. This study also analyzes and forecasts the fatigue failure area, which provides basis for preventing fatigue failure for implanted titanium plate. It has important significance to improve titanium plate service life and strength. It also could alleviate patients’ sufferings.

The plasma spraying Al2O3-13%TiO2 (abbreviated as AT-13) ceramic coatings on Q235B steel surface were dealed with laser remelting technique. The microstructure and properties before and after laser remelting were studied. Experiment results shown that the microstructure of laser remelted ceramic coatings was dense, no porosity appeared. The main compositions of laser remelted ceramic coatings were α-Al2O3 and a small amount of TiO2 and TiAl2O5. Microhardness of AT-13 plasma spraying coatings and laser remelting coatings were measured with vickers, and the maximum microhardness value of the former was 1000 HV0.2 , while that of the latter was 1700 HV0.2; The average bonding strength value of AT-13 plasma spraying coating was 24.36 Mpa, while the average bonding strength value of laser remelting coating was more than 67.02 Mpa. The wear resistance of laser remelting coatings was higher than that of AT-13 plasma spraying coatings through the pin-dish particle wear test.

In this paper, the current bicycle wheel was replaced by the ones which composed by the wheel hub with Glassfiber Reinforced Plastic (alkali free thin-walled cylinder material, hereinafter referred to as GFRP) material and the protective components made up of rubber outer pneumatic pad. With the help of the basic theory of elastic-plastic mechanics, the finite element “Nonlinear buckling” analysis of the wheel was carried out. The results show that the maximum elastic deformation of the wheel hub and the critical value of buckling failure load were restricted by the elasticity under the condition of external loads. Considering with the tensile strength and elastic modulus of the GFRP value of the material, it is demonstrated that the material is feasible to be used for wheel hub.