2,987 research outputs found

    Considerations for a design and operations knowledge support system for Space Station Freedom

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    Engineering and operations of modern engineered systems depend critically upon detailed design and operations knowledge that is accurate and authoritative. A design and operations knowledge support system (DOKSS) is a modern computer-based information system providing knowledge about the creation, evolution, and growth of an engineered system. The purpose of a DOKSS is to provide convenient and effective access to this multifaceted information. The complexity of Space Station Freedom's (SSF's) systems, elements, interfaces, and organizations makes convenient access to design knowledge especially important, when compared to simpler systems. The life cycle length, being 30 or more years, adds a new dimension to space operations, maintenance, and evolution. Provided here is a review and discussion of design knowledge support systems to be delivered and operated as a critical part of the engineered system. A concept of a DOKSS for Space Station Freedom (SSF) is presented. This is followed by a detailed discussion of a DOKSS for the Lyndon B. Johnson Space Center and Work Package-2 portions of SSF

    Integration of computer-aided design techniques into the mechanical product development process

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    Computer-Aided Design (CAD) has been called the most significant advance since the development of electricity. CAD is regarded as being the greatest breakthrough of modern times in the search for ways to improve the Product Development Process. This improvement is provided in terms of bringing to market better quality and higher performance products in a significantly shorter design/development cycle and at a lower cost. A survey of the various computer-aided design techniques is presented as they are currently being applied in the mechanical product development process. The research of these techniques includes the basic system operation from a user\u27s perspective, as well as discussion of the relative productivity improvements possible as compared with prior techniques and alternative approaches. The survey results are then enhanced through a case study of the more widely used CAD techniques available to a product design engineer. A typical benchmark part design of a thermoplastic clutch pawl was created and analyzed on some of the latest commercially available computer-aided design systems. This case study, conducted at Xerox Corporation, consisted of both wire frame, surface and solids geometry model creation, mass properties analysis, and finite element model structural analysis

    Overview of database projects

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    The use of entity and object oriented data modeling techniques for managing Computer Aided Design (CAD) is explored

    Evolution and Modern Approaches for Thermal Analysis of Electrical Machines

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    In this paper, the authors present an extended survey on the evolution and the modern approaches in the thermal analysis of electrical machines. The improvements and the new techniques proposed in the last decade are analyzed in depth and compared in order to highlight the qualities and defects of each. In particular, thermal analysis based on lumped-parameter thermal network, finite-element analysis, and computational fluid dynamics are considered in this paper. In addition, an overview of the problems linked to the thermal parameter determination and computation is proposed and discussed. Taking into account the aims of this paper, a detailed list of books and papers is reported in the references to help researchers interested in these topics

    Prototyping environment for robot manipulators

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    Journal ArticlePrototyping is an important activity in engineering. Prototype development is a good test for checking the viability of a proposed system. Prototypes can also help in determining system parameters, ranges, or in designing better systems. We are proposing a prototyping environment for electro-mechanical systems, and we chosen a 3-link robot manipulator as an example. In Designing a robot manipulator, the interaction between several modules (S/W, VLSI, CAD, CAM, Robotics, and Control) illustrates an interdisciplinary prototyping environment that includes different types of information that are radically different but combined in a coordinated way. This environment will enable optimal and flexible design using reconfigurable links, joints, actuators, and sensors. Such an environment should have the right "mix" of software and hardware components for designing the physical parts and the controllers, and for the algorithmic control for the robot modules (kinematics, inverse kinematics, dynamics, trajectory planning, analog control and computer (digital) control). Specifying object-based communications and catalog mechanisms between the software modules, controllers, physical parts, CAD designs, and actuator and sensor components is a necessary step in the prototyping activities. In this report a framework for flexible prototyping environment for robot manipulators is proposed along with the required sub-systems and interfaces between the different components of this environment

    On the application of model-based definition strategies to the delivery of technical training

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    ASME 2017 12th International Manufacturing Science and Engineering Conference (MSEC2017). June 4-8, 2017, Los Angeles, CA, USAThe application of computer technology to engineering and manufacturing domains has drastically transformed the way products and systems are designed and produced. However, a major drawback of CAD/CAM/CAE systems is the steep learning curve required to understand and master their extensive and increasingly complex set of functionalities. In this paper, we present a new approach to deliver CAD training materials that is inspired by Model-Based Definition (MDB) strategies, where annotated 3D models become the center of the training process. In our system, textual 3D annotations are connected to a Product Lifecycle Management (PLM) system to provide access to interactive video tutorials which are linked to specific features of a CAD model. As a proof of concerto to validate this approach, a plugin for a commercial CAD package was developed that enhances the functionality of standard 3D annotation mechanisms and enables users to interact with the technical training materials directly within the CAD interface. New data structures were implemented to support the connection and integration with PLM systems. A group of tutorials are described to illustrate the system architecture and implementation details

    The effects of an interactive computerized multimedia tutorial on knowledge gain in modular fixturing design concepts

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    This study was designed to compare student knowledge gain from learning modular fixturing design concepts by computer tutorial versus traditional lecture. The use of computer tutorial to support engineering and technology classroom instructions has been a major issue for many studies. The undergraduate curricula in engineering and technology are becoming increasingly complex due to the today\u27s modern wide variety of manufacturing processes. The concept of modular fixturing in tool design course is one of the technical competencies which most industries would like graduates to be able to apply their knowledge to real-world problems and situations. An interactive computerized multimedia tutorial named ToolTRAIN was developed and administered to undergraduate students in the Industrial Technology program at the University of Northern Iowa. By integrating information in a graphical manner such as 3D visualization through animation, ToolTRAIN demonstrated how several modular fixturing components can be assembled with a wide variety of workpieces. A quasi-experimental design employing pre- and post-instruction tests was utilized for the study. Two preexisting groups of students were assigned to either the experimental or control group. Both groups were instructed on the same general topics covered in this study. A pretest was given to both groups. Three hours were used to teach the control group the concepts and theories of modular fixturing design concepts by lecture. On the other hand, the experimental group was expected to utilize ToolTRAIN for three hours. The posttest was administered to all subjects to measure knowledge gain of modular fixturing design concepts after the instruction. The data were analyzed using t tests to compare group mean of change scores. All hypotheses were tested at the .05 level of significance. This research indicated that there were significant differences between the computer tutorial program and lecture method. The experimental (computer tutorial) group achieved significantly higher improvement in scores than the control (lecture) group. Also, the learning time actually spent using ToolTRAIN was less that for the control group. Based on this research it was concluded that the ToolTRAIN interactive multimedia tutorial program can be used as an effective teaching method for modular fixturing design concepts. Future research should expand the sample size used in the investigation with tighter control of control group module content. ToolTRAIN can also be used for more complex concepts of modular fixturing system and applications

    Robotic prototyping environment (Progress report)

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    Journal ArticlePrototyping is an important activity in engineering. Prototype development is a good test for checking the viability of a proposed system. Prototypes can also help in determining system parameters, ranges, or in designing better systems. The interaction between several modules (e.g., S/W, VLSI, CAD, CAM, Robotics, and Control) illustrates an interdisciplinary prototyping environment that includes radically different types of information, combined in a coordinated way. Developing an environment that enables optimal and flexible design of robot manipulators using reconfigurable links, joints, actuators, and sensors is an essential step for efficient robot design and prototyping. Such an environment should have the right "mix" of software and hardware components for designing the physical parts and the controllers, and for the algorithmic control of the robot modules (kinematics, inverse kinematics, dynamics, trajectory planning, analog control and digital computer control). Specifying object-based communications and catalog mechanisms between the software modules, controllers, physical parts, CAD designs, and actuator and sensor components is a necessary step in the prototyping activities. We propose a flexible prototyping environment for robot manipulators with the required sub-systems and interfaces between the different components of this environment
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