Advanced Materials Research Vols. 694-697

Abstract: To make a six-bar mechanism of shaper to be more reasonable, at first, the geometrical models of a couple of mechanisms were created by the ADAMS and the kinematical analysis on the models was carried out. The simulation results reveal the regulation that the displacement, velocity and acceleration of plough head of shaper vary with time. Through comparing the movement charts, we can not only gain the performance parameters of the mechanisms, but also evaluate more comprehensively the performance of a shaper. Then through parameterized modeling, how the length change of each rod of the mechanism to affect its performance was analyzed. Taking the minimization of mechanism maximum pressure angle and acceleration as the objective function, the optimal design of mechanism was implemented. This method to use ADAMS to conduct simulation and optimization greatly improves research efficiency and shortens product development cycle.

Abstract: The mathematical model of automobile driving was established, the calculation method of standing start acceleration time based on principle of optimal power continuous shift was introduced. The simulation analysis, calculation and verification were conducted by MATLAB. It lays the theoretical foundation for the analysis and calculation of dynamic performance by computer.

Abstract: Application of ANSYS parametric design language APDL built the model of workover rig derrick-guy line system. Take XJ70 type workover rig for example, optimization of derrick anchor pile piling position has been calculated under the condition of anchor pile ultimate uplift force. The uplift force obtained from pullout tests and different from soil type and soil condition. By optimizing calculation, on the premise of anchor pile bearing safety, the minimum and feasible piling positions have been gotten to guide piling work in special well site conditions. When the bearing capacity of soil decreased, make hook load as design variable, get the hook load limits at each pile position to ensure the ground anchor pile bearing safety.

Abstract: In this paper, it use Solid edge ST5 to establish the 3D model of manipulators designing for verifing the correctness of structure designing, and use ADAMS to simulate the sports of virtual prototyping for verifying the parameter of joints. Comparing the simulation results with theory of design structure, the scheme can fulfill the anticipative design requirements and successfully verify the feasibility of the design. In the design, it use Solid edge ST5 to establish the 3D model of manipulators designing, and use ADAMS to simulate the sports of virtual prototyping. Thus, we can reduce the design faults, shorten the test time, reduce the development costs to save the cost and improve the manipulator quality.

Abstract: The internal and outside tooth profile of the link plate in the new silent chain can simultaneously mesh with the sprocket when the tight side of silent chain is secant with the sprocket pitch circle in the traditional silent chain drive. The root of the outside tooth profile of the new silent chain is made up of the arcs and can mesh with the sprocket in order to reduce friction. Through the investigation on the transmission progress of new silent chain mechanism, the movement trajectory of the chain link and the sprocket is achieved. The result shows that the conjugate meshing, the small polygon action and the meshing friction reducing can be achieved through reasonably designing the tooth profiles of the link plate and the sprocket.

Abstract: In the article, the vibration resistance of spindle system in grinding head of roller grinding machine is studied by means of harmonic response and modal analysis, by using the method of the transfer matrix, obtained the first five orders of the natural frequency of spindle system. By studying the M84100A type spindle system in grinding head of roller grinding machine, obtained the conclusion that the natural frequency was far from the work frequency, so laid a foundation of the spindle system dynamic design.

Abstract: Fins, which are mounted at the rear of the underwater vehicles, have the action of stabilizing. X-fin and Cross-fin are two basic types of fins used in modern underwater vehicle. In the present paper, focused on the deep-sea autonomous underwater vehicle (AUV) developed by Tianjin University, influence of types and mounting positions of fins on the static stability (STS) of the AUV is investigated. Results show that AUV with Cross-fin has better STS and the mounting position of fins is the key influence on STS of AUV.

Abstract: In this paper, by using the DNV’s software SESAM, establishing the FPSO and mooring system model, a hull/mooring coupled dynamic analysis program in time domain is developed for the global motion simulation of a turret-moored, tanker based FPSO designed for 300m water depth. This paper especially concerns the dynamic response in the working condition and extreme condition. The analysis results show that the maximum response of surge in the working condition is 2.4542m and that of sway is 5.7532m, both of them are in safety range. In the extreme condition, the maximum response of surge is 28.748m and that of sway is 3.955m, FPSO has a large amplitude motion. The result can provide a reference for the design of FPSO system and have high application value.

Abstract: Considering the special load characteristics of the wheel loader, thispaper focus on compiling the load spectrum of the transmission of the wheelloader using the nonparametric statistical extrapolation method (NSEM). In thisprocess, the determination of the kernel function shape is the critical issue,which has been discussed in detail. Before extrapolating the sample loadspectrum, the signal denoising of the field-tested time-history load signals isperformed. After that, the sample load cycles are obtained using the rainflowcounting method and the corresponding kernel function shape is determined. Thenthe NSEM of rainflow matrix is proposed, by which the whole-life load spectrumis estimated. The proposed extrapolation method can well realize the estimationof the load cycles that do not appear in sample load cycles but may exist inthe whole-life load history.

Abstract: A crucial step to obtain a reliable fatigue life prediction is to determine a proper small load threshold below which the cycles at small loads or stresses with high frequency causing little fatigue damage are truncated from the original load time history. By taking both the peak over threshold theory and the endurance limit threshold into account, a proper small load threshold is proposed in this paper. The optimal threshold should be high enough to remove the high-frequency small cycles and low enough to minimize the loss of the fatigue damage which maybe be truncated by the empirical small-load omitting threshold. Based on this proper threshold, the fatigue life prediction will be more reliable.