New CAD for Rapid Prototyping

Volume 1: Design for Manufacturing Conference ◽

10.1115/96-detc/dfm-1414 ◽

1996 ◽

Author(s):

Shuichi Fukuda ◽

Daisuke Suzuki

Keyword(s):

Rapid Prototyping ◽

High Accuracy ◽

Layer By Layer ◽

Measurement Device ◽

Detailed Design ◽

Cad Systems ◽

Cad System ◽

Design And Manufacturing ◽

Cad Tool ◽

Very High

Abstract We developed a new CAD tool with special attention paid to rapid prototyping. Most of the present 3-D CAD systems treat geometry with very high accuracy but it is not easy to define or modify geometry as we do in the earlier stages of design. The present CAD systems, we believe, are more oritented toward the detailed design and manufacturing of the final product. As rapid prototyping itself is intended for the earlier stages of design, such a CAD system that permitts more easy or rough definition and modification of geometry is really desired. Most of the rapid prototyping systems generate 3-D geometry by piling up the 2-D sections layer by layer. So, if we develop such a layer-based CAD system, then we could more easily tranfer CAD data to the prototyping system. Such an idea was very old, but the traditional ones cannot manipulate geometry with much ease. What we aimed here is to develop a system that a designer can manipuate geometry as freely as he or she wishes. Thus, our system serves as a preprocessor to the present 3-D CAD systems. We are developing another system which permits to generate 3-D geometry as freely as if we are drawing it using a pen, based on the technology of 3-D measurement device. Couled with this system, the system we are proposing here is expected to tranfer such a 3-D geometry data very rapidly and easily to the prototyping equipment and also can interactively modify thus defined geometry data.

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Development of CAD System Based on Function Features

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.447-448.442 ◽

2010 ◽

Vol 447-448 ◽

pp. 442-446

Author(s):

Sonken Ando ◽

Ryo Ikeda ◽

Hideki Aoyama ◽

Norihito Hiruma

Keyword(s):

Three Dimensional ◽

3D Models ◽

Machining Process ◽

Data Generation ◽

Design Work ◽

Detailed Design ◽

Cad Systems ◽

Cad System ◽

Press Forming ◽

Attribute Information

Three-dimensional CAD systems contribute considerably to the detailed design processes of products. They are applied to the construction of 3D design models which are also utilized for design evaluation using a CAE system and for NC data generation using a CAM system. Since the functions of 3D CAD systems for constructing 3D models are increasingly being enhanced, they enable designers to easily construct 3D product models without design expertise. In detailed design work, designers are required not only to exactly define product shapes but also to assign attribute information such as dimensional tolerance, geometrical tolerance, roughness, machining process to be performed etc., which are essential for the manufacturing process. However, inexperienced designers often find it extremely hard to determine optimum attribute values and design values. In addition, it is more difficult to construct the required die/mold from the desired product shape taking into account forming errors caused by shrinkage during plastic injection and springback during press forming. This paper proposes a method to automatically assign required attribute information to each part of a designed product, to assist the model construction of a die/mold from a product shape, and to provide design support information on each part of a designed product to a designer. The proposed method is realized by assigning a Function Feature to each part; all the function features proposed in this paper are original. A CAD system based on the proposed method for injection molding and press forming was developed, and results of simple design experiments confirmed the usefulness of the CAD system and function features

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Direct Manipulation of Planar Geometry

Volume 4: Design for Manufacturing Conference ◽

10.1115/detc97/dfm-4419 ◽

1997 ◽

Author(s):

Shuichi Fukuda ◽

Tatsuya Asano

Keyword(s):

Concurrent Engineering ◽

Planar Geometry ◽

Direct Manipulation ◽

Cad Systems ◽

Large Plate ◽

Cad System ◽

Design And Manufacturing ◽

Cutting Out ◽

Integrate Design ◽

Mechanical Machining

Abstract Most of the presently available CAD systems are oriented toward generating the geometry of a whole product. But if we consider the problem of manufacturing, we sometimes wish to have such a CAD system that permits us to decompose the geometry of a final product so that we may make adequate decisions how to assemble pieces into the final shape. For example, if we consider welding, the decision where to weld does not necessarily reflect the welding engineers’ knowledge and experience. Rather, it is determined from other considerations such as design, mechanical machining, etc. But if we could take some portion of welding engineer’s knowledge and experience at the earlier stages of design, designers might change this design to make welding much easier to perform or to permit larger degree of allowances for mechanical machining, since large amount of heat will be inputted there later on by welding. Thus, a CAD system that permits such a decomposition of geometry is desired in order to integrate design and manufacturing and to achieve true concurrent engineering. In this work, a preliminary system has been developed which allows direct manipulation of only planer geomtry. But to consider that we do not have adequate systems which allow such decomposition for planer geometries and we still use CAD systems to work on a final geometry and different systems to determine the optimum plate cutting out of a large plate and further some other different systems to verify that the section to be welded will have enough strength, such a system would provide a first step toward realizing real concurrent engineering. Because there are many cases in welding where only planer geometries are used and if a final geometry can be decomposed into planer geometries, we would know that where it would be better to weld or how we can put them together.

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On the Rapid Prototyping Technologies and Applications in Product Design and Manufacturing

Materials Science Forum ◽

10.4028/www.scientific.net/msf.710.101 ◽

2012 ◽

Vol 710 ◽

pp. 101-109 ◽

Cited By ~ 1

Author(s):

Pulak M. Pandey

Keyword(s):

Rapid Prototyping ◽

Material Removal ◽

Solid Freeform Fabrication ◽

Functionally Graded ◽

Layer By Layer ◽

Data Preparation ◽

Freeform Fabrication ◽

Material Deposition ◽

Design And Manufacturing ◽

Graded Material

Material removal, forming, casting and joining are the established manufacturing approaches and processes based on these approaches are being practiced even in modern industries with appropriate automation. Layer by layer material deposition method to produce prototypes from a solid model is relatively new and was developed during last 10-15 years of 20th century. These processes were named as Rapid Prototyping (RP) or Solid Freeform Fabrication (SFF). Today there are many commercial RP system and most of these able to deposit liquid or solid/powder polymer based materials. Some systems are also able to deposit blends of polymer and metal or ceramic. Latest trend in this area is to deposit metals or alloys with variable composition and hence to produce functionally graded material. This paper describes in general the details related to RP processes, data preparation, and various commercial RP technologies. The article also discusses applications these processes.

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Analysing Mechanical Systems in Domestic and Foreign CAD Systems

Mechanical Engineering and Computer Science ◽

10.24108/0618.0001404 ◽

2018 ◽

pp. 10-17

Author(s):

V. A. Martynyuk ◽

V. A. Trudonoshin ◽

V. G. Fedoruk

Keyword(s):

Sheet Material ◽

The Finite Element Method ◽

Cad Systems ◽

Cad System ◽

Software Products ◽

Foreign Products ◽

Nonlinear Algebraic Systems ◽

Software Product ◽

Pipeline Design ◽

The Mathematical Model

The article considers applications of foreign CAD-systems in creating the challenging projects at domestic enterprises and design bureaus. As stated in the article "... presently, there is no domestic CAD-system that could completely replace such foreign products as NX, CATIA, Credo". Besides, due to international cooperation in creating the challenging projects (for example, the project to create a modern wide-body aircraft, proposed jointly with China), it makes sense to use the worldwide known and popular CAD systems (the aforementioned NX, CATIA, Credo). Therefore, in the foreseeable future, we will still have to use foreign software products. Of course, there always remains a question of the reliability of the results obtained. Actually, this question is always open regardless of what software product is used - domestic or foreign. This question has been haunting both developers and users of CAD systems for the last 30 to 40 years. But with using domestic systems, it is much easier to identify the cause of inaccurate results and correct the mathematical models used, the methods of numerical integration applied, and the solution of systems of nonlinear algebraic systems. Everything is much more complicated if we use a foreign software product. All advertising conversations that there is a tool to make the detected errors available to the developers, remain only conversations in the real world. It is easily understandable to domestic users, and, especially, to domestic developers of similar software products. The existing development rates and competition for potential buyers dictate a rigid framework of deadlines for releasing all new versions of the product and introducing the latest developments into commercial product, etc. As a result, the known errors migrate from version to version, and many users have accepted it long ago. Especially, this concerns the less popular tools rather than the most popular applications (modules) of a CAD system. For example, in CAD systems, the "Modeling" module where geometric models of designed parts and assembly units are created has been repeatedly crosschecked. But most of the errors are hidden in applications related to the design of parts from sheet material and to the pipeline design, as well as in applications related to the analysis of moving mechanisms and to the strength or gas dynamic analysis by the finite element method.The article gives a concrete example of a moving mechanism in the analysis of which an error was detected using the mathematical model of external influence (a source of speed) in the NX 10.0 system of Siemens.

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Stellar magnetic imaging from spectropolarimetric data

Symposium - International Astronomical Union ◽

10.1017/s0074180900083091 ◽

1996 ◽

Vol 176 ◽

pp. 53-60 ◽

Cited By ~ 1

Author(s):

J.-F. Donati

Keyword(s):

Small Amplitude ◽

High Accuracy ◽

Spectral Lines ◽

New Method ◽

Doppler Imaging ◽

Magnetic Imaging ◽

Active Stars ◽

Surface Fields ◽

Very High

In this paper, I will review the capabilities of magnetic imaging (also called Zeeman-Doppler imaging) to reconstruct spot distributions of surface fields from sets of rotationnally modulated Zeeman signatures in circularly polarised spectral lines. I will then outline a new method to measure small amplitude magnetic signals (typically 0.1% for cool active stars) with very high accuracy. Finally, I will present and comment new magnetic images reconstructed from data collected in 1993 December at the Anglo-Australian Telescope (AAT).

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Hole Accuracy during Deep Hole Drilling for Hydraulic Cylinder Application

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.984-985.67 ◽

2014 ◽

Vol 984-985 ◽

pp. 67-72 ◽

Cited By ~ 1

Author(s):

R. Clifford Benjamin Raj ◽

B. Anand Ronald ◽

A. Velayudham ◽

Prasmit Kumar Nayak

Keyword(s):

Feed Rate ◽

Drill Hole ◽

Hydraulic Cylinder ◽

High Accuracy ◽

Diameter Ratio ◽

Hole Drilling ◽

Deep Hole ◽

Deep Hole Drilling ◽

Very High ◽

Continuous Chip

Deep-hole drilling is a process in which the hole length will be very high when compared to diameter of the drill hole (i.e. length to diameter ratio will be greater than 5). Drilling a deep hole with very high accuracy is difficult process. The current project is about the production of deep hole with the aim to produce a chip which is not a continuous chip and also not a powdery chip. These conditions can be attained by varying the spindle speed and the tool feed rate.

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Evaluation of Parts Produced by a Novel Additive Manufacturing Process

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.315.63 ◽

2013 ◽

Vol 315 ◽

pp. 63-67 ◽

Cited By ~ 1

Author(s):

Muhammad Fahad ◽

Neil Hopkinson

Keyword(s):

Additive Manufacturing ◽

Rapid Prototyping ◽

Manufacturing Process ◽

High Speed ◽

Three Dimensional ◽

Coordinate Measuring Machine ◽

Layer By Layer ◽

Nylon 12 ◽

Measuring Machine ◽

End Use

Rapid prototyping refers to building three dimensional parts in a tool-less, layer by layer manner using the CAD geometry of the part. Additive Manufacturing (AM) is the name given to the application of rapid prototyping technologies to produce functional, end use items. Since AM is relatively new area of manufacturing processes, various processes are being developed and analyzed for their performance (mainly speed and accuracy). This paper deals with the design of a new benchmark part to analyze the flatness of parts produced on High Speed Sintering (HSS) which is a novel Additive Manufacturing process and is currently being developed at Loughborough University. The designed benchmark part comprised of various features such as cubes, holes, cylinders, spheres and cones on a flat base and the build material used for these parts was nylon 12 powder. Flatness and curvature of the base of these parts were measured using a coordinate measuring machine (CMM) and the results are discussed in relation to the operating parameters of the process.The result show changes in the flatness of part with the depth of part in the bed which is attributed to the thermal gradient within the build envelope during build.

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Cost Effective Swath Bathymetry

Marine Technology Society Journal ◽

10.4031/002533201788057982 ◽

2001 ◽

Vol 35 (4) ◽

pp. 33-45 ◽

Cited By ~ 3

Author(s):

Peter Hogarth

Keyword(s):

Processing Time ◽

Cost Effective ◽

High Accuracy ◽

High Coverage ◽

Swath Bathymetry ◽

World Survey ◽

Set Up ◽

Very High ◽

Harbor Area ◽

Wide Swath

Between 23rd and 25th July 2001 GeoSwath, a high specification shallow water wide swath bathymetry system, was used to survey the entire Portsmouth NH Harbor area. This paper deals with the results of this survey, illustrating the potential for significant reductions in the high costs, which have prevented widespread proliferation of Swath Bathymetry systems to date. Data, including a complete DTM gridded to 1 m resolution, will be presented and discussed in detail. These results show that the system is very easy to set up and use, requires greatly reduced boat and processing time, whilst offering high accuracy and very high coverage and resolution when used in a real-world survey of a dynamic harbor environment.

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Virtual Assembly Design Environment

ASME 1995 15th International Computers in Engineering Conference and the ASME 1995 9th Annual Engineering Database Symposium ◽

10.1115/cie1995-0816 ◽

1995 ◽

Author(s):

Hugh I. Connacher ◽

Sankar Jayaram ◽

Kevin Lyons

Keyword(s):

Virtual Reality ◽

Research Effort ◽

New Technology ◽

Natural Extension ◽

Virtual Assembly ◽

Software Systems ◽

Design Environment ◽

Cad System ◽

Assembly Design ◽

Design And Manufacturing

Abstract Virtual reality is a technology which is often regarded as a natural extension to 3D computer graphics with advanced input and output devices. This technology has only recently matured enough to warrant serious engineering applications. The integration of this new technology with software systems for engineering, design and manufacturing will provide a new boost to the field of computer-aided engineering. One aspect of design and manufacturing which may be significantly affected by virtual reality is design for assembly. This paper presents the ideas behind a current research effort aimed at creating a virtual assembly design environment and integrating that environment with a commercial, parametric CAD system.

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