Papers by Keyword: Dynamical Simulation

Abstract: Dynamical mathematical model was established for accurately positioning, fast response and real-time tracing of electro-hydraulic servo control system in railway vehicle bogie parameters test system with elastic load. The model could precisely control the output of position and force of the hydraulic cylinders. Induction methods was proposed in the paper. Dynamical simulation verified the mathematical model by software simulink. Meanwhile the key factors affecting the dynamical characteristics of the system were discussed in detail. Through the simulation results, high precision is obtained in application and the need of real-time control on the railway vehicle bogie parameters test-bench is realized .

Abstract: Swing movable teeth reducer is a new type of small teeth difference planetary gear transmission. As a new product development technology, virtual prototype technology is a digital design method based on the product simulation model. It is important to carry on the performance simulation of the reducer and seek the optimization design of the products on virtual prototype technology. Based on the study on the principle and structure of the swing movable teeth transmission, it analyzed the motion of the system, carried on the dynamical simulation of the swing movable teeth reducer, which is established on the virtual prototype. At the same time, the paper analyzed the dynamical simulation on the rotational speed and force of the mainly parts.

Abstract: The dynamic simulation analysis method is adopted to investigate the dynamic damping characteristics of lathe tool with large length to diameter (L/D) ratio. The multi flexible body dynamical simulation model of dynamical damping lathe tool with large length to diameter ratio is built up according to the actual experiment lathe by using the software ADAMS and ANSYS. Simulation analysis of the multi flexible body dynamical model which has been optimized shows that the system damping performance is improved greatly. On this basis the relationship of rubber bush, mass body and vibration absorption cavity is discussed. And the result of the discussion indicates that the shape of rubber bush should be confirmed by repeatedly simulating the model.

Abstract: Based on finite element analysis and explicit Euler method, the present study visualized the dynamical simulation of a knotless netting in R environment. In the physical models, the linking between knot and twine were considered as a mass-spring system. Vector algebra methods were applied to analyze the hydrodynamic forces and tensile forces of the spring. To solve the equations numerically, explicit Euler method was introduced for the mechanical system to achieve the stable solutions. A package of scatterplot3d in R program was transferred to realize the visualization of the knotless netting in three-dimensional space. The results of dynamical simulation were displayed distinctly to show the sinking processes and equibibrium state of the knotless netting in the sea water.

Abstract: Swing movable teeth reducer is a new type of small teeth difference planetary gear reducer, which is used to transmit the rotary motion and power between two shafts with same axis. It is important to carry on the systematic design and performance simulation of the reducer and seek the optimization design of the products by the virtual prototyping. Based on the study of the principles and characteristics of the swing movable teeth transmission, this study established the virtual prototype and achieved the dynamical simulation of the reducer by CAD/CAE software. The rotate speed and force analysis proved the feasibility of the model.

Abstract: In this paper, we point out several problems on fluid mechanics existing in the abrasive flow finishing, and study the dynamic simulations methods in the area. A case study is conducted on the process of free abrasive flow finishing, where we complete the dynamic simulations on the kinematic characteristics by a model of two-phase fluid. It is shown that the theory of two-phase fluid can practically direct the design of polishing machine, and the selection as well as the optimization of parameters for polishing technique.

Abstract: Improving the cutting performance, especially the cutting quality of sugarcane harvesters is the most magnificent problem for popularizing the application of the havesters. Much research has been done on most effect factors but rare on the influence of rigidity enhancement of sugarcane cutter. Indeed, the rigidity of sugarcane cutter has notable influence on the quality of sugarcane cutting，as it effects its vibration and the vibration in turn brings great damage to the cutting quality. This paper analyzes how the rigidity of sugarcane cutter effects its working vibration by building up its mathematical model, then further investigates it by making a dynamical simulation analysis to compare two cutter structures with different rigidity based on ANSYS and ADAMS, and validate the actual effect of enhancing the cutter rigidity through a physical experiment. The result shows enhancing the rigidity of the cutter could lead to notable improvement of sugarcane cutting quality.

Abstract: A new hybrid-control structure for the compensation of the volume-delay negative effect in the mixed-gas pressure control is designed. The volume-delay mechanism is discussed. A Smith predictor is used in the primary loop of a cascade control system where the secondary loop has a negligible delay while the primary loop has a significant and variant delay. To deal with the sensitivity of Smith predictor to modeling error, the gas pipe model for the Smith predictor can be updated by measuring the gas pressure and choosing the model characteristics through a lookup table. The results show that the proposed control structure brings together the best merits of a cascade control and the Smith predictor structure, and it can provide a better performance than the traditional cascade control.

Abstract: The build-in dynamical vibration absorption system with damping is applied to increase the dynamic stiffness of a boring bar. According to construction and vibration features, multi flexible body dynamical model of the vibration absorption system is built up by using the software of ADAMS and ANSYS. Also the vibration characteristic of an actual boring bar is analyzed by using SA-78 2ch FFT analyzer. Through the analysis of simulation results and experimental data the accuracy of the model is validated. On this basis the influence of the radial stiffness coefficient of rubber brushes, the damping coefficient of damping fluid and the mass of heavy turning body on the vibration system is discussed by using the vibration analyses module of ADAMS. The simulation results verify the feasibility of the initial structure design; establish the design key points in the actual design. The multi flexible body dynamical model of the vibration absorption system has been simulated, optimized and analyzed. And optimized parameters are obtained finally. With these optimized parameters, actual dynamical vibration absorption boring bar with damping can be designed, and the dynamic stability of the bar is enhanced thereby.

Abstract: When designing forging manipulators, the bending moments transmitted to the manipulator through the workpiece due to the press motions should be reduced to avoid damage to the manipulator and the workpiece. A resilient system is designed to this purpose. This paper investigates the dynamic behavior of the forging manipulator due to press motions, which focuses on the bending moment transmitted to the manipulator. The Forging manipulator parameters assume primary importance in design, such as the clamp mass, resilient stiffness, resilient damping. A parametric study is committed to provide some helpful solutions for forging manipulator design.