Applied Mechanics and Materials Vols. 184-185

Abstract: Multifunctional mobile bed-chair is designed base on human body engineering principles, it has several functions such as mobility, sitting up, bend knees and sleeping flat. We determine the size of components in both back raising mechanism and bend knees mechanism with geometric mapping method to satisfy the requirements of movement and work space. With the soft of ADAMS to optimize and simulate the motion of the bed-chair, the optimization goal is minimization of maximum value of the angular acceleration of both the back rod in back raising mechanism and leg rod in bend knees mechanism. Finally, we got the satisfied size of mechanisms.

Abstract: Based on the preprocessed measuring data, this paper proposes a method for identification and reconstruction of regular curves and surfaces including straight line(segment), circle(arc), four-sided plane and right cylindrical surface. Considering the geometric feature of each kind of regular curve or surface, the paper studies the corresponding algorithm for identifying the curve or surface point set, reconstructs the curve or surface and gives the parameter equation.

Abstract: In this paper, a cylinder involute gear model is established in AUTOCAD2007 software. SAT file format is imported in the ANSYS software and contact stress on gear meshing position is analyzed. The stress distribute drafts of the gear is obtained so that it is convenient to check the bending strength of the root of the gear and the fatigue contact strength of the face of the gear. The result is similar to the real situation. The whole process of model construction, analysis shows that ANSYS software is a reliable and effective tool which could provide theoretical basis to the gear teeth strength designation.

Abstract: On the basis of the analysis of special demand of helical gear of automotive transmission, gear precision modeling and finite element analysis of bending stress were carried out in this paper. In UG three-dimensional modeling environment, helical gear model was generated and imported into ANSYS software. Then the meshing on the geometric model and influence on gear strength with different radius of root fillet were discussed. The paper provided certain methods to guide the gear parametric design, strength analysis and improve optimization design efficiency of transmission gear parts.

Abstract: For the high hoisting height, wide using range, tower crane is widely utilized in the architecture construction, while there are some deficiencies in the high rising architecture such as chimney, so the performance can’t exerted. By virtue of computer aided technology, the finite element static analysis of metallic structure of unconventional dedicated tower crane is conducted in this paper, and the figures of stress and displacement are achieved for the two working conditions and two structures. It is proved that the results are satisfied the requirements of stiffness and strength, and also foundation is established for the further analysis.

Abstract: The relationship between the porosity and the mechanical property was still a bottle-neck in bone tissue engineering scaffold. Porosity increasing may reduce the scaffold strength. In order to solve the contradiction, the idea of enhancing the mechanical properties by controlling the scaffold porosity was proposed in this paper. Using reverse engineering technology, 5 different porosity cranium scaffolds were first established. Their FE models were built through FE surface preprocessing and volume fitted meshing. According to results of static analysis, the displacements and stresses of the 5 porosity scaffolds were compared and discussed and it indicated that the 36% porosity bionic scaffold have good porous level and mechanical properties.

Abstract: Objective To set up a three-dimensional (3-D) finite element (FE) model of Less Inwasive Stabilization System (LISS) intreating distal femoral fractures(AO /33-A3), and make preliminary biomechanical analysis, which can provide a scientific basis for future clinical application. Methods To obtain information of the spatial structure of the femur by CT scan, then to build their three-dimensional solid model using of software, and use three-dimensional reverse engineering to obtain three-dimensional model of LISS. The model was assembled using the ABAQUS, then meshed and simulated axial compression force, the stress distribution of femur and LISS plate. Results The largest stress of the LISS focuses on the edge of the plate and the region which is close to the femur.

Abstract: This paper mainly solved the 3D modeling and force analysis of double telescopic mast about the real structure of ZY18000/32/70D hydraulic support. According to the GB of mast standard, computer simulation was manipulated for double telescopic mast about ZY18000/32/70D hydraulic support by not only 1.5 times rated axis load strength analysis but also 1.1 times rated load and eccentric 30mm buckling analysis. Through analysis and simulation tests，not only the distribution and deformation of the double telescopic mast about ZY18000/32/70D hydraulic support but also the stress distribution and simulation conditions were got about mast. Thus, theoretical basis could be provided for the design of double telescopic mast about ZY18000/32/70D hydraulic support.

Abstract: The frame of 4MPa vertical type high-pressure grouting machine is used as the research object. The finite element analysis software ANSYS is applied to the modal finite element analysis of the frame. The first five order natural frequencies and the corresponding vibration modes of the frame are obtained, and then the influence of every mode shape on the performances of the frame was discussed. It provides a reference for the dynamic structural design and optimization of the frame of vertical type high-pressure grouting machine.

Abstract: In the previous study, the rigid model of flapping wing rotor ignores the flexible factors to describe its in detail. So a new flexible wing model is established here to further study the aerodynamic characteristic of this wing. And a variable-speed factor is taken into account in this new model too. It is found that the deformation position and amplitude are both useful to increase aerodynamic force. The variable-speed factor has a significant effect on aerodynamic characteristic. In the end, the results show the flexible wing has much better performance than rigid one.