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CADCAM education and training
EDUCATION
GEOMETRIC DESIGN
CADCAM education and training
R e d u c i n g t h e degree o f high o r d e r p a r a m e t e r i z e d curves
A Llewelyn (CADCAM Association,
Cambridge~ UK) This paper sets out the background to the work of the Committee for CAD Education and Training and the circumstances which caused it to be formed, namely the acknowledged need for education and and training of a quality and quantity sufficient to produce technologically aware teachers and managers and the skilled engineers and technicians required by industry. The study, which formed one of the main activities of the Committee, was carried out over a two-year period through an intensive series of workshop discussions supplemented by collection and analysis of data from many sources. The initial results are summarized to provide a reference within which educational and training courses relevant to CAD and its application to CADCAM can be identified in terms of job descriptions which industry can understand.
G Mullineux (Deportment of Engineering Mathematics, Loughborough University of Technology, UK) The use of parametrically defined curves and surfaces is important in CAD and drafting as it gives a flexible means for producing and describing smooth shapes. It is common to use polynomials of low degree to generate the coordinate functions, but higher order ones provide more degrees of freedom and can arise from the ways in which low order ones are manipulated. This paper looks at the problem of replacing a given order parametric curve by a computationally more simple low order one which yields approximately the same curve shapes. It examines not only the problem of generating the coordinate functions but also gives a technique for changing the parameterization in order to improve accuracy. Dr Mullineux is a lecturer in the Department of Engineering Mathematics at Laughborough University of Technology, UK. His current research interests are in the geometrical and mathematical aspects of CAD.
ted. On these we build algorithms for geometry calculations on B-spline curves: intersection with a hyper-plane and second degree surface, extremal points, points closest to a given point, points with specified tangent or curvature and points with extremal curvature. Tar Dokken graduated from the University of asia in 1978. His thesis was on local B-spline approximation methods. He has been working on the CAD/CAM projects GPM and SPICS. He is now working on the joint German/Norwegian CAD/CAM project APS. He is employed at the Central Institute for Industrial Research, asia, Norway, and lectures on computer graphics at the University of Oslo. D e f i c i e n t spline m e t h o d R Loh (Peking University, The People's Republic of China)
In this paper we suggest a cubic parametric deficient spline method and introduce its application to Coons surfaces. This method is constructed on local procedures. We can control its geometric shape by the length of tangent vector, so it is a shape preserving interpolating method. Its continuity is C 1 .
M o d u l a r C A A D courses - a vehicle t o discuss C A A D e d u c a t i o n R Schijf (Faculty of Architecture, Delft, The Nether/ands) Computer education for architects and architectural students is a major bottleneck in the introduction of computers to architecture. The paper outlines a course consisting of five modules from which schools may choose a combination to be inserted into their own curriculum. The modules are very adaptable to varying teaching environments. Initial experience with some modules is reported.
C A B D in e d u c a t i o n and practice A Bridges (ABACU$, Deportment of Architecture, University of Strathclyde, UK) This paper, after restating the problem of the adequacy of existing courses in computer-aided building design, discusses several aspects of CAD education. The scope of CAD is defined and its potential as a learning resource described. Various problems such as the need for education at different levels from undergraduate to midcareer, and the provision of resources in both human and technical aspects, are discussed and possible solutions presented. The inter-related roles of teaching, research and practice are defined. Finally an educational framework is presented, from which could develop a range of variants and modules appropriate to the spectrum of needs within the building industry. Alan Bridges is an architect specializing in computer applications in architecture. His main interests are in the fields of CABD education, design methodology and computer graphics.
v o l u m e 14 n u m b e r 2 m a r c h 1 9 8 2
How to make the bicubic patch work using r e p a r a m e t r i s a t i o n A A Ball (Deportment of Engineering Mathematics, University of Technology, Loughborough, UK) The paper comprises a series of examples in numerical surface definition, loosely strung together, to show the practical limitations of the bicubic patch and how they can be overcome by reparametrization. The concept of reparametrization is more general than that previously used in computer-aided geometric design insofar as it is modelled in addition to the basic parametric equation. The equation form offers the prospect of a simple surface definition procedure that works just as a designer expects. A A Ball has been a lecturer in engineering mathematics at Loughborough University of Technology since 1977. His research interests are in CAD, and finite-element analysis. He has seven years industrial experience with BAC (Warton) in the CAD Department and Stress Office and is the originator of CONSURF.
S o m e g e o m e t r y c a l c u l a t i o n s on B-spline curves T Dokken (Central Institute for Industrial
Research, Oslo, Norway) B-splines are used as the standard storage format for all curve geometry in the sculptured surface module of the inter-Nordic CAD/CAM project GPM. The geometry resulting from the calculations is stored in standard formats, while data structures take care of how the geometry was defined. A set of lower level geometry functions is presen-
DRAFTING SYSTEMS: BUILDING DESIGN
C o m p u t e r d r a f t i n g systems in construction - the buyer's problem I Hamilton (Construction Industry Computing Association, Cambridge, UK) J R F Burdett (Building Research Establishment, UK) This paper reviews the opinions, ideas and experience of developers of computer drafting systems for use by the building construction and design professions and the users of such systems, with a view to identifying those features which are necessary for their successful application in building design. D u m b d r a w i n g systems and k n o w l e d g e engineering A Bijl (EdCAA D, University of Edinburgh,
UK) The link between drawing systems and knowledge of users' work-practices is discussed and illustrated by examples of experience at EdCAAD, highlighting the significance of knowledge engineering to practical CAAD applications. Aart Bijl graduated from the University of Cape Town with a BArch. He had his own design office in Cape Town and practised in the Netherlands before coming to the UK in 1962. In 1965 he joined the Architecture Research Unit and was subsequently appointed reader in the Department of Architecture, University of Edinburgh in 1981. Since 1968 he has been directing EdCAAD Studies at the University.
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GEOMETRIC DESIGN
CADCAM education and training
R e d u c i n g t h e degree o f high o r d e r p a r a m e t e r i z e d curves
A Llewelyn (CADCAM Association,
Cambridge~ UK) This paper sets out the background to the work of the Committee for CAD Education and Training and the circumstances which caused it to be formed, namely the acknowledged need for education and and training of a quality and quantity sufficient to produce technologically aware teachers and managers and the skilled engineers and technicians required by industry. The study, which formed one of the main activities of the Committee, was carried out over a two-year period through an intensive series of workshop discussions supplemented by collection and analysis of data from many sources. The initial results are summarized to provide a reference within which educational and training courses relevant to CAD and its application to CADCAM can be identified in terms of job descriptions which industry can understand.
G Mullineux (Deportment of Engineering Mathematics, Loughborough University of Technology, UK) The use of parametrically defined curves and surfaces is important in CAD and drafting as it gives a flexible means for producing and describing smooth shapes. It is common to use polynomials of low degree to generate the coordinate functions, but higher order ones provide more degrees of freedom and can arise from the ways in which low order ones are manipulated. This paper looks at the problem of replacing a given order parametric curve by a computationally more simple low order one which yields approximately the same curve shapes. It examines not only the problem of generating the coordinate functions but also gives a technique for changing the parameterization in order to improve accuracy. Dr Mullineux is a lecturer in the Department of Engineering Mathematics at Laughborough University of Technology, UK. His current research interests are in the geometrical and mathematical aspects of CAD.
ted. On these we build algorithms for geometry calculations on B-spline curves: intersection with a hyper-plane and second degree surface, extremal points, points closest to a given point, points with specified tangent or curvature and points with extremal curvature. Tar Dokken graduated from the University of asia in 1978. His thesis was on local B-spline approximation methods. He has been working on the CAD/CAM projects GPM and SPICS. He is now working on the joint German/Norwegian CAD/CAM project APS. He is employed at the Central Institute for Industrial Research, asia, Norway, and lectures on computer graphics at the University of Oslo. D e f i c i e n t spline m e t h o d R Loh (Peking University, The People's Republic of China)
In this paper we suggest a cubic parametric deficient spline method and introduce its application to Coons surfaces. This method is constructed on local procedures. We can control its geometric shape by the length of tangent vector, so it is a shape preserving interpolating method. Its continuity is C 1 .
M o d u l a r C A A D courses - a vehicle t o discuss C A A D e d u c a t i o n R Schijf (Faculty of Architecture, Delft, The Nether/ands) Computer education for architects and architectural students is a major bottleneck in the introduction of computers to architecture. The paper outlines a course consisting of five modules from which schools may choose a combination to be inserted into their own curriculum. The modules are very adaptable to varying teaching environments. Initial experience with some modules is reported.
C A B D in e d u c a t i o n and practice A Bridges (ABACU$, Deportment of Architecture, University of Strathclyde, UK) This paper, after restating the problem of the adequacy of existing courses in computer-aided building design, discusses several aspects of CAD education. The scope of CAD is defined and its potential as a learning resource described. Various problems such as the need for education at different levels from undergraduate to midcareer, and the provision of resources in both human and technical aspects, are discussed and possible solutions presented. The inter-related roles of teaching, research and practice are defined. Finally an educational framework is presented, from which could develop a range of variants and modules appropriate to the spectrum of needs within the building industry. Alan Bridges is an architect specializing in computer applications in architecture. His main interests are in the fields of CABD education, design methodology and computer graphics.
v o l u m e 14 n u m b e r 2 m a r c h 1 9 8 2
How to make the bicubic patch work using r e p a r a m e t r i s a t i o n A A Ball (Deportment of Engineering Mathematics, University of Technology, Loughborough, UK) The paper comprises a series of examples in numerical surface definition, loosely strung together, to show the practical limitations of the bicubic patch and how they can be overcome by reparametrization. The concept of reparametrization is more general than that previously used in computer-aided geometric design insofar as it is modelled in addition to the basic parametric equation. The equation form offers the prospect of a simple surface definition procedure that works just as a designer expects. A A Ball has been a lecturer in engineering mathematics at Loughborough University of Technology since 1977. His research interests are in CAD, and finite-element analysis. He has seven years industrial experience with BAC (Warton) in the CAD Department and Stress Office and is the originator of CONSURF.
S o m e g e o m e t r y c a l c u l a t i o n s on B-spline curves T Dokken (Central Institute for Industrial
Research, Oslo, Norway) B-splines are used as the standard storage format for all curve geometry in the sculptured surface module of the inter-Nordic CAD/CAM project GPM. The geometry resulting from the calculations is stored in standard formats, while data structures take care of how the geometry was defined. A set of lower level geometry functions is presen-
DRAFTING SYSTEMS: BUILDING DESIGN
C o m p u t e r d r a f t i n g systems in construction - the buyer's problem I Hamilton (Construction Industry Computing Association, Cambridge, UK) J R F Burdett (Building Research Establishment, UK) This paper reviews the opinions, ideas and experience of developers of computer drafting systems for use by the building construction and design professions and the users of such systems, with a view to identifying those features which are necessary for their successful application in building design. D u m b d r a w i n g systems and k n o w l e d g e engineering A Bijl (EdCAA D, University of Edinburgh,
UK) The link between drawing systems and knowledge of users' work-practices is discussed and illustrated by examples of experience at EdCAAD, highlighting the significance of knowledge engineering to practical CAAD applications. Aart Bijl graduated from the University of Cape Town with a BArch. He had his own design office in Cape Town and practised in the Netherlands before coming to the UK in 1962. In 1965 he joined the Architecture Research Unit and was subsequently appointed reader in the Department of Architecture, University of Edinburgh in 1981. Since 1968 he has been directing EdCAAD Studies at the University.
109