- Email: [email protected]
Quantum mechanics
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a direct data transfer to NC and cutting and wall panel assembly machinery. The system could save significant amounts of detail design and production control time. The individual contributions in this session all had something of interest and, although taken together they were a heterogeneous mix, there was an impression of movement towards practical achievements in the application of computers.
John Chalmers
Standards A growing concern at the CAD80 was standards for software. Not only is software being distributed widely and
used by groups probably not anticipated by the original developers, but the software is being used to guide design decisions in increasingly significant ways. The papers by M V Jones and Alan Bridges nicely set out these issues and proposed some initial resolutions to them. In the future, the current decentralized process for making design decisions will result in situations where computer software is blamed for design failures. The software, however, will probably not be controlled by the developer. The only security for a computer user (and the developer) in such a case is outside certification of the software. Limited examples of certification already exist, for example,
~'~~'~"~'~'~~'~iiiiiiiiliiiiiiiii!ii!i!i
for building code checking of structures. But what happens when this becomes the rule, rather than the exception? Certification may be offered only on particular implementations that have been evaluated. What about the bootlegging of analyses from one machine to another? And how are complex programs verified? These knotty conflicts will become increasingly important as computing tools become more dispersed in design. They suggest the need for new organizations and suggest directions that few in CAD have anticipated.
C M Eastman
Interactive computer graphics facilities and applications Interactive computer graphics facilities and applications 28 March 1980, University of Leeds. Organized by the Computational Physics Group of the Institute of Physics
This meeting was designed as an up-to-date forum for examining current facilities for interactive computer graphics and their current exploitation. Concentration was on areas such as biophysics, plasma physics, design and modelling in engineering, PCB-(printed circuit board) design, and computerassisted physics teaching. General principles were emphasized rather than particular details, to enable those who attended to appreciate the scope and application of interactive graphics to their own area of interest. Dr Hubbold, Director of the Computer Graphics Unit, University of Manchester spoke on graphics facilities and what is available. He outlined a wide range of hardware such as interactive display systems, input devices and tools, hardcopy pen and electrostatic plotters, and graphics system configurations. Display systems included storage tubes, refresh calligraphic and raster-scan displays.
volume 12 number 6 november 1980
Of particular interest today is the availability of colour raster-scan terminals at comparatively low cost. These offer the advantages of multicolour high density flicker-free pictures with area fill, shading, and selective erasure. If the speed of the latter is sufficient, dynamically changing pictures are possible. Professor North outlined the use of an interactive display system to study molecular conformations in the Department of Biophysics, University of Leeds. The advantages of computer representation of a molecule chain are precision; ease of modification of the model; ease of selection of portions of the model; superimposition of two models; and ability to evaluate quickly any properties which depend on structure (eg energy). Dr K BrOdlie, chairman of the GHOST Users Group, and Mr D Hallam, chairman of the GINO-F Users Group, outlined the software facilities in GHOST80 and NAG, and in GINO-F respectively. GINO-F was described using an example in the design of aircraft. GHOST80 was an updated version of GHOST with additional routines, more variety of character and axis annotation facilities, new character fonts and provision for raster graphics. Four application areas of inter-
active computer graphics were presented: plasma physics research (T ] Martin, Culham Laboratory), mechanical engineering and CAD (Dr A de Pennington, University of Leeds), PCB design and manufacture (Dr H J Kahn, University of Manchester), and computer-assisted physics teaching (Dr M J Cox, University of Surrey). Mr T J Martin outlined the role that interactive programs (especially graphics programs) played in solving problems in connection with the nuclear fusion programme at Culham Laboratory. These facilities had been for dispersion equations and designing and analysing magnetic fields used for plasma containment. In the first area, human visual intuition was required to select certain possible solutions from an infinite number. A combination of numerical algorithms and graphics (GHOST) had been used to do this, with great success. This analytical plus graphical approach had been extended into the second area - that of magnetic fields for plasma. Examples were shown of superconducting levitrons, stellarators and the Joint European Torus, all of which had been designed using a combination of these techniques.
319
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Dr A de Pennington outlined work in CAD and CAM at the University of Leeds. These included: • mathematical theories for modelling, representing rigid solids and computing the geometric properties of such solids • computational representations and algorithms to operate on such solids • experimental software systems which embody such representations and algorithms. The use of graphical techniques were an essential part of each of the areas of design, analysis and manufacture. For example, in CAM it is essential to 'examine' the cutter path of machine tool in producing a component to check for possible interference before generating instructions for the tool.
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Dr Kahn indicated the wide range of problems associated with the design and manufacture of PCBs. These include logic design, assignment of components to boards, placement, interconnection tracking, and artwork generation. Interactive graphics had been used in these areas.
Quantum mechanics Dr Cox spoke of using interactive graphics in physics teaching covering such topics as mathematical calculations, analysing experiments, numerical methods and simulation of experiments. The power of graphics was utilized in the explanation of such topics as interference, quantum mechanics, 0article mechanics, turbulence and particle trajectories. The student was able to interact
::
:
:
:
:
,:
:
with the system to see the effect of changing parameters. This was essentially computer-assisted learning with a high visual content. In conclusion, this meeting brought out a number of important developments taking place in computer graphics. First, on the hardware side, the increasing diversity of displays which are available - with intelligence at relatively low cost. Second, the increasing variety of applications which seek to utilize computer graphics. Graphics bring together the capability and intuition of the human and the power and resources of the machine into an effective union for further developments in a particular area.
R A Earnshaw University of Leeds, UK
Computer-aided drafting and geometric modelling Computer-aided drafting and geometric modelling, 23 April 1980. Organized by Oyez, IBC, London This seminar attracted a wide-ranging audience covering turnkey system manufacture#s and software system suppliers in addition to the more normal mix of managers, engineers and computer specialists. Chaired by Arthur Llewelyn, who gave the introductory paper, the theme was defined as software tools for drafting and modelling set in the context of CAD/CAM systems. These are required to be flexible and adaptable to suit the conditions found in different industries. The name of the game was stated as the interlinking of hardware and software components and, above all, the ability to use and interchange data between software packages and computer systems. Speakers described third generation software designed to handle 2D drafting and 3D modelling within CAD/CAM systems. As a number of speakers emphasized, the first generation of software had failed because the emphasis was on technique and not on solving the problems.
320
The new systems described, MEDUSA by Chris Fell of CIS and ROMULUS by Charles Lang of Shape Data showed that past lessons had been taken to heart.
Finite~lement analysis In both cases software facilities were being provided for incorporation in CAD/CAM systems, which were able to be interfaced to other software packages, for finite element analysis or NC tape production. It was freely admitted that current systems, whilst providing practical tools for most situations, still had limitations. An insight into the problems of providing complete 3D descriptions and further R&D being undertaken was provided by B Wordenweber, of the CAD Group at Cambridge University. He described BUILD as an investigative tool to explore geometric modelling possibilities, particularly provision of a suitable interface for finite-element analysis. G Armstrong of Leeds University in the same vein described a collabora-
tire project in geometric modelling with five industrial firms and sponsored by the UK Department of Industry. The emphasis here was placed on the means by which the mechanical designer can input data and build up not only a complete geometric description, but also full representational information about the model. The presentations were concluded by B Walker of Ferranti Cetec who illustrated the characteristics of a CAD/CAM system. He gave practical examples of how geometric models were used in design and manufacturing, citing the productivity gains and benefits obtained when the model database is fully used for assembly, stock control and general management.
Panel discussion The proceedings were rounded off by a lively panel discussion with good audience participation. Perhaps the most interesting point to emerge concerned future trends in CAD/CAM systems and relationships between users and suppliers. Would firms continue to put together and develop basic kits of
computer-aided design
a direct data transfer to NC and cutting and wall panel assembly machinery. The system could save significant amounts of detail design and production control time. The individual contributions in this session all had something of interest and, although taken together they were a heterogeneous mix, there was an impression of movement towards practical achievements in the application of computers.
John Chalmers
Standards A growing concern at the CAD80 was standards for software. Not only is software being distributed widely and
used by groups probably not anticipated by the original developers, but the software is being used to guide design decisions in increasingly significant ways. The papers by M V Jones and Alan Bridges nicely set out these issues and proposed some initial resolutions to them. In the future, the current decentralized process for making design decisions will result in situations where computer software is blamed for design failures. The software, however, will probably not be controlled by the developer. The only security for a computer user (and the developer) in such a case is outside certification of the software. Limited examples of certification already exist, for example,
~'~~'~"~'~'~~'~iiiiiiiiliiiiiiiii!ii!i!i
for building code checking of structures. But what happens when this becomes the rule, rather than the exception? Certification may be offered only on particular implementations that have been evaluated. What about the bootlegging of analyses from one machine to another? And how are complex programs verified? These knotty conflicts will become increasingly important as computing tools become more dispersed in design. They suggest the need for new organizations and suggest directions that few in CAD have anticipated.
C M Eastman
Interactive computer graphics facilities and applications Interactive computer graphics facilities and applications 28 March 1980, University of Leeds. Organized by the Computational Physics Group of the Institute of Physics
This meeting was designed as an up-to-date forum for examining current facilities for interactive computer graphics and their current exploitation. Concentration was on areas such as biophysics, plasma physics, design and modelling in engineering, PCB-(printed circuit board) design, and computerassisted physics teaching. General principles were emphasized rather than particular details, to enable those who attended to appreciate the scope and application of interactive graphics to their own area of interest. Dr Hubbold, Director of the Computer Graphics Unit, University of Manchester spoke on graphics facilities and what is available. He outlined a wide range of hardware such as interactive display systems, input devices and tools, hardcopy pen and electrostatic plotters, and graphics system configurations. Display systems included storage tubes, refresh calligraphic and raster-scan displays.
volume 12 number 6 november 1980
Of particular interest today is the availability of colour raster-scan terminals at comparatively low cost. These offer the advantages of multicolour high density flicker-free pictures with area fill, shading, and selective erasure. If the speed of the latter is sufficient, dynamically changing pictures are possible. Professor North outlined the use of an interactive display system to study molecular conformations in the Department of Biophysics, University of Leeds. The advantages of computer representation of a molecule chain are precision; ease of modification of the model; ease of selection of portions of the model; superimposition of two models; and ability to evaluate quickly any properties which depend on structure (eg energy). Dr K BrOdlie, chairman of the GHOST Users Group, and Mr D Hallam, chairman of the GINO-F Users Group, outlined the software facilities in GHOST80 and NAG, and in GINO-F respectively. GINO-F was described using an example in the design of aircraft. GHOST80 was an updated version of GHOST with additional routines, more variety of character and axis annotation facilities, new character fonts and provision for raster graphics. Four application areas of inter-
active computer graphics were presented: plasma physics research (T ] Martin, Culham Laboratory), mechanical engineering and CAD (Dr A de Pennington, University of Leeds), PCB design and manufacture (Dr H J Kahn, University of Manchester), and computer-assisted physics teaching (Dr M J Cox, University of Surrey). Mr T J Martin outlined the role that interactive programs (especially graphics programs) played in solving problems in connection with the nuclear fusion programme at Culham Laboratory. These facilities had been for dispersion equations and designing and analysing magnetic fields used for plasma containment. In the first area, human visual intuition was required to select certain possible solutions from an infinite number. A combination of numerical algorithms and graphics (GHOST) had been used to do this, with great success. This analytical plus graphical approach had been extended into the second area - that of magnetic fields for plasma. Examples were shown of superconducting levitrons, stellarators and the Joint European Torus, all of which had been designed using a combination of these techniques.
319
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Dr A de Pennington outlined work in CAD and CAM at the University of Leeds. These included: • mathematical theories for modelling, representing rigid solids and computing the geometric properties of such solids • computational representations and algorithms to operate on such solids • experimental software systems which embody such representations and algorithms. The use of graphical techniques were an essential part of each of the areas of design, analysis and manufacture. For example, in CAM it is essential to 'examine' the cutter path of machine tool in producing a component to check for possible interference before generating instructions for the tool.
!!~ i!!~!iii:i! i! 2! !:~::!:!i~i~i!!~!ii!i!~iii:!:!i:i! ii!!;ii: :~:::~:!!!~iii!i~!iii:!:ii~i!!:!2! i!i:::!:~:i:::: !!!!2:!:::: ::
Dr Kahn indicated the wide range of problems associated with the design and manufacture of PCBs. These include logic design, assignment of components to boards, placement, interconnection tracking, and artwork generation. Interactive graphics had been used in these areas.
Quantum mechanics Dr Cox spoke of using interactive graphics in physics teaching covering such topics as mathematical calculations, analysing experiments, numerical methods and simulation of experiments. The power of graphics was utilized in the explanation of such topics as interference, quantum mechanics, 0article mechanics, turbulence and particle trajectories. The student was able to interact
::
:
:
:
:
,:
:
with the system to see the effect of changing parameters. This was essentially computer-assisted learning with a high visual content. In conclusion, this meeting brought out a number of important developments taking place in computer graphics. First, on the hardware side, the increasing diversity of displays which are available - with intelligence at relatively low cost. Second, the increasing variety of applications which seek to utilize computer graphics. Graphics bring together the capability and intuition of the human and the power and resources of the machine into an effective union for further developments in a particular area.
R A Earnshaw University of Leeds, UK
Computer-aided drafting and geometric modelling Computer-aided drafting and geometric modelling, 23 April 1980. Organized by Oyez, IBC, London This seminar attracted a wide-ranging audience covering turnkey system manufacture#s and software system suppliers in addition to the more normal mix of managers, engineers and computer specialists. Chaired by Arthur Llewelyn, who gave the introductory paper, the theme was defined as software tools for drafting and modelling set in the context of CAD/CAM systems. These are required to be flexible and adaptable to suit the conditions found in different industries. The name of the game was stated as the interlinking of hardware and software components and, above all, the ability to use and interchange data between software packages and computer systems. Speakers described third generation software designed to handle 2D drafting and 3D modelling within CAD/CAM systems. As a number of speakers emphasized, the first generation of software had failed because the emphasis was on technique and not on solving the problems.
320
The new systems described, MEDUSA by Chris Fell of CIS and ROMULUS by Charles Lang of Shape Data showed that past lessons had been taken to heart.
Finite~lement analysis In both cases software facilities were being provided for incorporation in CAD/CAM systems, which were able to be interfaced to other software packages, for finite element analysis or NC tape production. It was freely admitted that current systems, whilst providing practical tools for most situations, still had limitations. An insight into the problems of providing complete 3D descriptions and further R&D being undertaken was provided by B Wordenweber, of the CAD Group at Cambridge University. He described BUILD as an investigative tool to explore geometric modelling possibilities, particularly provision of a suitable interface for finite-element analysis. G Armstrong of Leeds University in the same vein described a collabora-
tire project in geometric modelling with five industrial firms and sponsored by the UK Department of Industry. The emphasis here was placed on the means by which the mechanical designer can input data and build up not only a complete geometric description, but also full representational information about the model. The presentations were concluded by B Walker of Ferranti Cetec who illustrated the characteristics of a CAD/CAM system. He gave practical examples of how geometric models were used in design and manufacturing, citing the productivity gains and benefits obtained when the model database is fully used for assembly, stock control and general management.
Panel discussion The proceedings were rounded off by a lively panel discussion with good audience participation. Perhaps the most interesting point to emerge concerned future trends in CAD/CAM systems and relationships between users and suppliers. Would firms continue to put together and develop basic kits of
computer-aided design