Modeling and Simulation on Axial Piston Pump Based on Virtual Prototype Technology

A particular emphasis is placed on the virtual prototype technology （VPT） of axial piston pump. With this technology it is convenient and flexible to build a complicated 3D virtual based on real physical model. The actual kinematics pairs of the parts were added on the model. The fluid characters were calculated by hydraulic software. The shape of the parts, the flexible body of parts, etc were improved in this prototype. So the virtual prototype of piston pump can work in computer like a real piston pump, and the flow ripple, pressure pulsation, motion principle, stress of parts, etc can be investigated. The development of the VPT is introduced at the beginning, and the modeling process of the virtual prototype is explained. Then a special emphasis is laid on the relationship between the dynamics model and the hydraulic model, and the simulations on the flow ripple, pressure pulsation, motion principle, the stress and strain distribution of the middle shaft and piston are operated. Finally, the advantages and disadvantages of the VPT are discussed. The improved virtual prototype of piston pump more tally with the real situation and the VPT has a great potential in simulation on hydraulic components.

RESEARCH AND DEVELOPMENT OF VIRTUAL PROTOTYPE OF RUNNING GEARS FOR RAILWAY VEHICLE

Virtual prototype is an important idea to resolve design problems of railway vehicle. A different development method, which is based on national product and autonomous development, and would like to reflect the specialty of railway vehicle development in China, is presented. According to the developing process of railway vehicle, the research contents and developing method are pointed out. The integration between CAD and performance analysis software on dynamics and strength is mainly considered. In CAD environment, the properties for dynamics computing are extracted directly from the model and exported with model. This method can avoid data losing caused by model rebuilding in CAE software, and increase the direct dependence of product CAD. Then the vehicle model with properties will be used for real-time dynamics and kinematics analysis and simulation. Therefore, the strength of the parts can be analyzed. The results of dynamics and strength analysis will be fed back to optimize the design model. All operations are dispatched by a control platform, and all data are managed according to the principle of PDM. Testing results show this method is correct.

Virtual Prototype Simulation and Reliability Analysis for Drive System of Armored Chassis

Drive system is the key device of armored chassis. Its working state and reliability influence the maneuver performance of armored chassis directly. In order to simulate the failure process and evaluate the service reliability of drive system in training or battle missions,a new kind of dynamic simulation model and driving simulation platform of the complete drive system were established based on virtual prototype and finite element technology in this paper. Using the platform, the kinematics and dynamic characteristics of drive system were studied and analyzed in detail,the dynamic load spectrum of key components was obtained,the service life was predicted, and the service reliability evaluation results were provided. A simulation example of transmission gear was shown to illustrate the simulation and evaluation process. The result proves that the simulation method not only can be used to compute and evaluate the service reliability of complex mechanical mechanism, but also has high precision and reasonable computational cost. Therefore,simulation and reliability analysis based on virtual prototype of the armored chassis drive system will provide scientific reference for the formulation of armored chassis reasonable repair cycle.

Top-level modeling theory of multi-discipline virtual prototype

Multi-disciplinary virtual prototypes of complex products are increasingly and widely used in modern advanced manufactur- ing. How to effectively address the problems of unified modeling, composition and reuse based on the multi-disciplinary heteroge- neous models has brought great challenges to the modeling and simulation （M＆S） science and technology. This paper presents a top-level modeling theory based on the meta modeling framework （M2F） of the COllaborative SIMulation （COSlM） theory of virtual prototyping to solve the problems. Firstly the fundamental prin- ciples of the top-level modeling theory are decribed to expound the premise, assumptions, basic conventions and special require- ments in the description of complex heterogeneous systems. Next the formalized definitions for each factor in top level modeling are proposed and the hierarchical nature of them is illustrated. After demonstrating that they are self-closing, this paper divides the top- level modeling into two views, static structural graph and dynamic behavioral graph. Finally, a case study is discussed to demon- strate the feasibility of the theory.

The Design of Inverted Pendulum System Based on Virtual Prototype Technology and PID Control

A design scheme of a single Inverted Pendulum Virtual Prototype based on the combination of software and hardware is introduced.It uses hardware platform of C8051F020 single chip and the software of Matlab,Visual Basic and Kingview.It can simulate the force and movement of Inverted Pendulum expediently and intuitively.The combination of software and hardware makes the system closer to the reality.The concrete scheme is introduced in the paper and the result of PID control which verifies the correctness of the scheme.

Virtual Prototype Modeling and Simulation of Pipe Wagon Articulating System

Virtual prototype of pipe wagon articulating (PWA) system has been developed and simulated based on the kinematics and dynamics of machinery and Automatic Dynamic Analysis of Mechanical Systems (ADAMS) software. It has been integrated with real-time three dimensional (3-D) system simulations for detailed and responsive interaction with dynamic virtual environments. By using this virtual model, the conceptual design examination and performance analysis of the PWA system have been realized dynamically in virtual laboratory. System dynamic force, displacement and tension of pipe have been measured through verifying this 3- D virtual prototype. By comparing the static tension and dynamic tension of pipe, the difference between the two kind tensions has been found. The simulated dynamic tension is much greater than the static tension obtained from the static theory. The results attained in this work suggest that the conceptual designed PWA system can meet the requirements of the operation.

Digital Design of Virtual Prototype based on Multidisciplinary Design Optimization

In order to obtain digital design of complex mechanical product as optimal as possible in an efficient way,multi- discipline integrated design method is proposed,which integrates multidisciplinary design optimization (MDO) into digital design process to design virtual prototype (VP) efficiently.Through combining MDO and multi-body system dynamics,MDO integra- tion platform,which takes VP as the core,is constructed.Then automated MDO design of VP is realized and changes of mechani- cal design project can be expressed intuitively during MDO design process.The proposed approach is also demonstrated by using inte- grated analyzing flow of vehicle engineering design.The result shows that the method not only can feasibly realize the MDO of VP, but also can solve the optimization problem of vehicle multi-body system dynamic performance.It can be adopted to the digital de- sign of other complex system.

Firing Stability of Rarefaction Wave Gun Based on Virtual Prototype

The dynamics characteristics of rarefaction wave gun( RAVEN) in launching are studied. Based on its characteristics of structure and interior ballistics, the launch dynamic model and virtual prototype of RAVEN are established. After simulating and solving by ADAMS software, through comparison RAVEN to conventional gun,influences of some structural parameters on firing stability are acquired. Optimization analysis of structural parameters of gun based on analysis of the firing stability is done. It puts forward the theoretic basis for improving firing stability and security.

Control method for semi-active suspension based on virtual prototype

The simple dynamic model is often adopted to deal with control questions in research on semi-active suspension. The model has more theoretic meanings than authentic ones because of difference between practical and physical models. The virtual prototype has remarkable advantages in its application simulation processes. It is not only faster and more veracious, but also of better visualization of the simulation results.

The Impact Study of Three-axis Servo System Interference Torque based on Virtual Prototype

The three-axis servo system with the core of gyro stabilization is the foundation to realize its function, and a key technology of the seeker devolopment. In order to reduce the costs, improve the efficiency of research and devolopment, a new method that instead of physical prototype by virtual prototype was proposed. Adams and MATLAB/simulink are used to establish the mechanical dynamics model and controller model of the three-axis servo system. The simulation data which was processed and analyzed is compared with test data, to determine the control parameters of the virtual prototype and improve the accuracy of the model, and test the multiple condition simulation,which can provide a reference for practical production.The simulation results verify the feasibility of the models.

Study on conditions of internally carried air-launched launch vehicles based on the virtual prototype technology

A method based on the virtual prototype technology simulating the separation of a launch vehicle from its aircraft in the aircraft wake was proposed based on the internally carried air-launched launch vehicle program.In this method,the full-scale model of the aircraft,the vehicle and the parachute are constructed.Then,they are imported into the ADAMS software,constraint solutions and driving forces are then added for visual dynamic simulation.The unsteady aerodynamic forces of the vehicle in the aircraft wake are calculated by CFD and the moving grid technique.The forces generated by the parachute can be derived from the Kirchhoff motion equation.Through comparing and analyzing the simulation results under different launch conditions,it has been proven that this method simulates the separation of a launch vehicle from the aircraft in the aircraft wake accurately.It provides the foundation for the aggregate project of internally carried air-launch vehicles,and offers a new referenced method for multi-body dynamic simulation.

Simulation and Optimization of Amplitude-adjusting Performance of Crane with Virtual Prototyping Technology

In the design of crane,designers often have to study the trajectory of amplitude-adjusting of crane.The tradition- al methods,illustration and analytics both show their limits.In this paper,the simulation of process of amplitude-adjusting is presented and the optimization is also performed with virtual prototyping technology.From the comparison of original solution and optimal solution,the effectiveness of this technique is testified.On the platform ADAMS/View,the interactive optimization can be performed in a visual,intuitive and credible way,which deserves to be introduced to the design of crane.

A Hyper-redundant Elephant’s Trunk Robot with an Open Structure:Design,Kinematics,Control and Prototype

As for the complex operational tasks in the unstructured environment with narrow workspace and numerous obstacles,the traditional robots cannot accomplish these mentioned complex operational tasks and meet the dexterity demands.The hyper-redundant bionic robots can complete complex tasks in the unstructured environments by simulating the motion characteristics of the elephant’s trunk and octopus tentacles.Compared with traditional robots,the hyper-redundant bionic robots can accomplish complex tasks because of their flexible structure.A hyper-redundant elephant’s trunk robot(HRETR)with an open structure is developed in this paper.The content includes mechanical structure design,kinematic analysis,virtual prototype simulation,control system design,and prototype building.This design is inspired by the flexible motion of an elephant’s trunk,which is expansible and is composed of six unit modules,namely,3UPS-PS parallel in series.First,the mechanical design of the HRETR is completed according to the motion characteristics of an elephant’s trunk and based on the principle of mechanical bionic design.After that,the backbone mode method is used to establish the kinematic model of the robot.The simulation software SolidWorks and ADAMS are combined to analyze the kinematic characteristics when the trajectory of the end moving platform of the robot is assigned.With the help of ANSYS,the static stiffness of each component and the whole robot is analyzed.On this basis,the materials of the weak parts of the mechanical structure and the hardware are selected reasonably.Next,the extensible structures of software and hardware control system are constructed according to the modular and hierarchical design criteria.Finally,the prototype is built and its performance is tested.The proposed research provides a method for the design and development for the hyper-redundant bionic robot.

Simulation of Vertical Planetary Mill Based on Virtual Prototyping

The mechanical model of vertical planetary mill is set up, whose dynamic and kinetic characteristics are described as well. Based on the analysis of system dynamics of vertical planetary mill, virtual prototyping technology is applied in the simulation of this mill. The development of virtual prototype of equipment, virtual test and optimization of virtual prototype are stated in detail. Some useful conclusions which have theoretical meaning for the manufacturing of vertical planetary mill have been obtained. Furthermore, it is pointed out that virtual prototyping technology shows great advantage and is bound to become a main method of developing product in the future.

Control Performance Evaluation of Serial Urology Manipulator by Virtual Prototyping

Prostatic hyperplasia and tumor are common diseases,and the minimally invasive surgery inserting the instruments through the urethra into the prostate is commonly conducted.Taking the robotic manipulator for such surgery into consideration,this paper analyses the workspace of the end effector,and proposes the distribution error of the fixed point and the tracking error of manipulator end effector on the cone bottom surface of the workspace as the basis for control implementation of the manipulator.The D-H coordinate system of the manipulator is established and the trajectory planning of the end effector in the Cartesian space is carried out.The digital model was established,and dynamics simulation was performed in Solidworks and Matlab/Simulink environment to guide the manipulator design.Trajectory mapping and synchronization control between virtual model and the actual manipulator are realized based on digital twin technique.The virtual manipulator can reflect the real-time state of the manipulator with data interaction by comparing the dynamics simulation results with the motor current values obtained by experiment.Experiment was carried out with PD feedback control and Newton-Euler dynamics based feedforward control to get the trajectory tracking characteristic of each motor,errors of the fixed point and tracking performance of the end effector of the manipulator.The results show that compared with PD feedback control,feed forward control implementation can achieve a reduction of 30.0%in the average error of the fixed point of the manipulator and a reduction of 33.3%in the maximum error.

Modeling and simulation of ocean mining subsystem based on virtual prototyping technology

According to the virtual prototyping technology and the theory of dynamics of multi-rigid-body system, a virtual prototyping of ocean mining vehicle was constructed by using 3-dimensional entity modeling software ((Pro/E),) automatic dynamic analysis of mechanical systems(ADAMS) and advanced visual software(AVS). After 32 new modules were developed with C++ at AVS platform, the interface problems of the 3 types of software were solved effectively and a visual environment for ocean mining subsystem was constructed. Based on the similarity (theory) and similarity experiments, the validity and reliability of the virtual prototyping were verified. By using the (constructed) virtual prototyping, the relevant parameters, such as cutting depth, rotation speed of roller,marching speed of mining vehicle can be adjusted one by one. After repeatable virtual tests and analysis its corresponding dynamic characteristics, the structure parameter of mining vehicle and the parameter of mining process can be optimized fast and accurately. The experiment and simulation results show that, under the controlled mining parameters, 4 function expressions between the average force of single pick,average torque,average cutting power,energy consumption ratio and cutting depth are obtained. The maximum force of a single pick is less than (11090N) and the maximum torque of the roller is less than 3600N·m.

Study on co-simulation model of forging manipulator based on virtual prototyping

Based on the characteristics of integrated virtual prototype technology,the mechanical system sub-model,the hydraulic system sub-model and the control system sub-model of a forging manipulator system have been built using a variety of software,and a forging manipulator multidisciplinary cosimulation model has been also built using a method of simulation models interface.Then the simulation and experiment are finished,and the result of the experiment is in good agreement with the result of the simulation.It shows that the co-simulation model established can simulate accurately parameter changes in real time during the moving of the forging manipulator such as displacement,velocity and pressure flow,which is of important significance for the optimized design of the forging manipulator system to establish the models.

Analysis of Robot Accuracy Assessed via its Joint Clearance by Virtual Prototyping Method

This paper discusses how joint clearance influences robot end effectorpositioning accuracy and a robot accuracy analysis approach based on a virtual prototype isproposed. First, a 5-DOF(Degree of freedom) neurosurgery robot was introduced. Then we built itsvirtual prototype, made movement planning and measured the manipulator tip accuracy, through whichthis robot accuracy portrait was obtained. Finally, in order to validate the robot accuracyanalysis approach which is based on a virtual prototype, the result was compared with that from amodel built by robot forward kinematics and robot differential kinematics. The robot accuracyanalysis approach presented in this paper gives a new way to enhance robot design quality , and helpto optimize the control and programming of the robot.

Development of a Special Machine Rotating Cutter Based on Virtual Prototyping

We first describe the fundamental concept of virtual prototyping（ VP ） technology and discuss the differences among VP, computer aided design, computer aided engineering and computer aided manufacture. Then we present the application flow of virtual prototyping technology to the development of mechanical products. Based on ADAMS/VIEW, a new kind of special machine rotating cutter has been developed. The simulation results show that the rotating cutter meets the design requirements. It is concluded that virtual prototyping technology is quite valuable in designing and manufacturing mechanical product.

Functional Virtual Prototyping in Vehicle Chassis Reform Analysis and Improvement Design

The contribution of functional virtual prototyping to vehicle chassis development is presented. The different topics that we took into consideration were reform analysis and improvement design during the vehicle chassis development. A frame of coordinates based on the digital-model was established, the main CAE analy- sis methods, multi-body system dynamics and finite element analysis were applied to the digital-model build by CAD/CAM software. The method was applied in the vehicle chassis reform analysis and improvement design, all the analysis and design projects were implemented in the uniform digital-model, and the development was carried through effectively.