Papers by Keyword: Virtual Prototyping

Abstract: In the last 40 years CAD engineering has taken a considerable advantage in all domains. This has been imposed by the changes that have occurred in most of the environments with which engineering interacts in general, as well as by the technological advancement that has made the use of computers that have become increasingly efficient and are now indispensable to the technology [1]. The tendency of this period was consumer because prices fell as a consequence of globalization, the technique evolved, the standards became very rigorous, and the laws began to protect the consumer more.

Abstract: The topic of this paper focuses on the virtual interactive prototyping and augmented reality prototyping. The prototyping of the manufacturing systems is of utmost importance. The prototyping phase is also important for maintenance for manufacturing systems. The paper propose a new approach taking into account several key ideas concerning the manufacturing machine components. The overall objectives of this paper are to propose new models and techniques for virtual prototyping and augmented reality.

Abstract: In the first stage of research, real bone components were analyzed to determine the main visual geometric shapes. After that, it was used a CT or MRI device to get parallel sections of studied bone components. In the third stage, the images were transferred to a 2D CAD software like AutoCAD, where the outer and inner contours of the bone were approximated by polygonal lines composed of multiple segments. To obtain virtual bones was used a parametric CAD software that allows defining models with a high degree of difficulty. The contours were transferred to a 3D CAD software, which, step by step, each section was used to define each virtual component of bone. For some components, such as vertebrae, bones of the jaw, the skull bones, was used in a preliminary model consists of curves in parallel planes. Based on this model can be defined the main curves for the final virtual 3D solid model. Also, were defined innovative orthopedic metal components as tibia nail, plates and screws or prosthetic elements. Were defined simulations to determine the behavior of the new orthopedic models through FEA method.

Abstract: Mechanical transmissions are frequently used in renewable energy systems (RES), either as speed reducers in solar tracking systems (e.g. worm drive, planetary gear), or as speed increasers in small hydropower converters or wind turbines. Most of them are conventional transmissions characterized by large overall dimensions and/or low efficiencies; therefore, new mechanical transmissions with higher performances are highly investigated. The paper presents the development of an innovative chain planetary transmission for hydro/wind applications. The speed increaser transmission requires a well-defined transmission ratio according to the application (3 – 5 for hydro, 6 – 30 for wind), good efficiency, relative simple and compact structure, easy maintenance, and low-cost. The final proposed solution overcomes some limits of the RES transmissions, significantly increasing the efficiency while decreasing the system size and eliminating the chain pre-stressing. The steps of the product design process applied for innovative generation of high performance mechanical transmissions are shown in the Part I. The proposed chain planetary transmission integrated into a micro hydropower application is analyzed in the Part II: virtual prototyping, experimental testing and optimization stages and results are detailed.

Abstract: The energy of DC arc influences the electrical life and reliability of relay’s contacts seriously. The study on shortening the arc duration by increasing the breaking velocity of contacts is important for reducing the contacts erosion and improving the contacts life. Firstly, it was indicated that increasing the breaking velocity is effective for reducing the arc time of this differential electromagnetic relay through life test, especially the breaking velocity of N.O. contacts. Then a new optimal model of spring system suitable for this relay was analyzed in increasing the breaking velocity. Secondly, electromagnetic model, mechanical model, dynamic simulation model, vibration model and thermal model of the optimal relay were built based on virtual prototyping. Finally, the optimal design was verified on the virtual prototyping platform and the results shows that the breaking velocity of N.O. contacts increases more than 100%, which provides the optimal scheme of improving the relay’s electrical life.

Abstract: Vehicle ride comfort determines vehicle performance, affects the ride comfort and reliability. Aimed at the problems in establishing the vehicle dynamics model by traditional classical mechanical methods, the vehicle ride comfort simulation analysis scheme on the basis of virtual prototyping technology is put forward. Based on Multi-body dynamics, the virtual prototype vehicle model was established. According to the national standards, the vehicle ride comfort simulation scheme was designed, including the simulation test with sine wave excitation, the simulation test on triangular bump road and random uneven road. Through the test, the root mean square of weighed acceleration can be got and the evaluating process can be accomplished according to the ISO standard. The results show a good ride comfort of the testing vehicle. Virtual test provides a useful reference for the complex mechanical product design of physical prototype.

Abstract: The effects of joints with clearance between Crankshaft and cycloidal wheel on needle pendulum gear drive in 2K-V reducer are considered by Virtual Prototyping. A comparative analysis reveals angular velocity, acceleration change and the loading conditions of the input and output components. Joggle force between Crankshaft and cycloidal wheel are also analysized. It is a convenient way for stiffness design of 2K-V reducer.

Abstract: A novel technique for determining the energy-optimal base position of common Industrial Robot (IR) is presented. At first, an energy-focused IR model is developed by means of the Modelica/Dymola simulation environment. Then, for a given IR task, a standard but efficient optimization technique is employed, which allows to determine the robot base position corresponding to the minimum energy consumption. A set of graphical maps is finally provided, which allows a rapid estimation of the energy demand along with the time required for the task completion.

Abstract: To re-create a 3D parametrical environment it was used a CAD software which permits to define complex models. First, there were defined the main bone components as femur, tibia and pelvis by using the CT images. The contours of the CT images were transferred to CAD environment where, step by step, and section by section, the virtual bones were defined. The model of the pelvis and of the lower limbs during a virtual walking was recomposed by using kinematic parameters determined by filming the human subject. In this case the entire behavior of each bone component was determined, including that of the tibia. The variations of force and torque which auctioned over the tibia were determined and applied to the fractured tibia with the new models of nails.

Abstract: This paper approaches the optimization of the control system for an industrial robot with 6 axes (degrees of freedom), using design of experiments (DOE) and multiple linear regression models. The design objective refers to the desired trajectory of the end-effector, the aim being to minimize the difference between the desired (imposed) and current (measured) angles in the revolute joints of the robot. The correlation between the imposed trajectory of the end-effector and the corresponding angular motions in the six revolute joints is obtained through the inverse kinematic analysis. The characteristic parameters of the controllers are used as design variables in the optimization. The optimal design is based on the DOE Screening investigation strategy with the Full Factorial design type. This design was chosen in order to evaluate the effect of the factors and of their interaction on trajectory, and the levels of these factors needed to produce an optimal trajectory. By comparing actual data with data after optimization, it shows that the regression function is correct (in terms of goodness of fit). The dynamic model of the robotic system was developed in mechatronic concept, by integrating the mechanical device (designed in ADAMS/View) and the control system (MATLAB/Simulink) at the virtual prototype level. The optimization study is performed by using ADAMS/Insight.