International Baccalaureate: Design & Technology
Option E: Computer-aided Design, Manufacture and Production
This option is concerned with understanding how computer-based technologies have transformed the nature of the design and manufacture of products. It considers the impact of the application of such technologies on the role of the designer and manufacturer and the associated implications for the consumer. The development of CAD/CAM has radically changed production processes causing a fundamental rethink of the relationship between designer, manufacturer and consumer.
E.1 The Impact of CAD on the Design Process
E.1.1
Consider the range of packages for different design applications, eg for architecture where the software package can calculate the building costs or for engineering and product design applications. State that many CAD software packages exist, each of which offer particular facilities and advantages.
E.1.2
Discuss the advantages and disadvantages of these packages for designers
E.1.3
State that there are a number of different computer modelling techniques. Spreadsheet packages can be used for numeric modelling, 2D and 3D modelling techniques, and exploded views.
E.1.4
Explain the criteria that enable designers to select appropriate computer modelling techniques.
E.1.5
Define animation and virtual reality
E.1.6
Compare animation with virtual reality. Consider the advantages and disadvantages of each for particular design contexts.
E.1.7
Describe a design context where the use of virtual reality helps to conserve resources. Consider time, materials, energy and cost.
E.1.8
Explain how various input devices can be used by a CAD system including a scanner, digital camera, graphics tablet and video camera. Details of how these devices function or communicate with the computer are not required.
E.1.9
Explain how various output devices can be used by a CAD system, including a printer and plotter.
E.2 The Impact of CAD/CAM on Manufacturing
E.2.1
Explain how a numerically controlled (NC) machine aids manufacturing with reference to the quality of reproduction, the reduction in the need for operators, and speed. Use an example to illustrate the improvement on previous practices.
E.2.2
Explain how a computer numerically controlled (CNC) machine further aids manufacturing. Refer to greater flexibility, reprogrammability and multi-machine control.
E.2.3
Explain how CAD and CNC can be interfaced to produce a CAD/CAM system. Graphics produced on a CAD system are translated to a set of programming coordinates which instruct the CNC machines how to manufacture the design seen on the screen.
E.2.4
Outline how sewing machines, knitting machines and looms can be interfaced in a CAD/CAM system to produce textile products. No detail of baud and code is needed. Refer to scanning, layers, management of materials and interface.
E.2.5
Explain how lathes, milling machines or shapers can be interfaced in a CAD/CAM system to produce metal, plastic or wood products. Refer to the interface; x, y, z axis coordinates and management of materials.
E.2.6
Outline how an engraver is interfaced in a CAD/CAM system to produce printed circuit boards (PCBs). Refer to x, y axis coordinates, interface, accuracy, detail and size.
E.2.7
Define computer integrated manufacturing (CIM)
E.2.8
Outline one example of a CIM system.
E.2.9
Discuss the advantages and disadvantages of CIM to both consumers and manufacturers.
Advantages: more choice, can design in own requirements, more consistent quality, cheaper products, parts easily manufactured and changed, random introduction of parts, less lead time, less labour and waste, better machine utilization, improvements in productivity and quality control, greater consistency, fewer errors and waste, and higher quality of finish.
Disadvantages: high initial investment and personnel, training cost, job losses, lack of individuality.
E.3.1
Define Just-in-time (JIT) and Just-in-case (JIC)
E.3.2
Explain the advantages and disadvantages of JIT to manufacturing.
Advantages: saving on storage space, increased efficiency, reduced capital investment, reduced work in progress and fewer unsold items
Disadvantages: possible stoppages due to non-delivery of external components, communication breakdown, distribution and transport breakdown
E.3.3
Explain the advantages and disadvantages of JIC to manufacturing.
Advantages: “buffer”, goods-in-stock in case of unforeseen circumstances (eg non-delivery of supplies) and rapid changes in demand
Disadvantages: unsold stock, space needed for storage and capital investment
E.3.4
Discuss the impact of CAD/CAM on working conditions and work force. Include the number of employees, their skills required, organization of the work place and the working environment (health and safety).
E.3.5
Discuss the impact of CAD/CAM and its associated processes on quality control.
E.3.6
Compare two manufacturers that produce similar products one of whom is using CAD/CAM.
E.3.6–E.3.7
Advantages of CAD/CAM: Quality control including greater consistency, fewer errors, reduction of waste and the higher quality of finish. Greater variety of choice, opportunity to design in their own
requirements, get more consistency of quality, cheaper products. Families of parts easily manufactured and changed. Random introduction of parts, less lead time, better machine utilization, less labour, productivity improvements, less waste, quality control.
Disadvantages of CAD/CAM: High initial investment, training personnel. Job losses, lack of individuality. Changes in the number of employees, their skills required, organization of the work place and the working environment (health and safety).
E.3.7
E.3.8
Discuss the implications of computerized manufacture on the infringement of copyright and patent laws. Include ease of copying and changing designs.
E.3.9
Outline a product which can be manufactured either by CAD/CAM or by a more traditional process.
For example, flat pack or self-assembly furniture compared to traditional cabinet making techniques, children’s toys, spaghetti production and commercial products.
E.3.10
Refer to skills involved, efficiency of production, quality control, precision and wastage, ability to change the product during manufacture, variety, quantity, complexity and economics. Compare the two manufacturing processes for the product chosen in E.3.9.
E.3.11
Refer to complexity of design, consistency of design, quality and cost. Evaluate the product manufactured in E.3.9 by the two manufacturing processes.
E.4 The Impact on the Consumer
E.4.1
Explain how CAD/CAM has improved the type and range of products available to the consumer. Many common artefacts require such precision in their manufacture that without CAD/CAM it would not be possible to produce them.
E.4.2
Discuss how CAD/CAM has affected consumer choice. Include interior design packages to model environments before choosing and implementing, eg kitchen design available in retailer showrooms, and car showrooms that enable you to input option and colour requirements and have those passed directly to manufacturing tracks.
E.4.3
Discuss how the CAD/CAM system can be designed to allow for the needs of individual consumers. Include consumer culture and society, obsolescence, energy, individual needs, waste, lifestyles and recycling.
E.4.4
Discuss the impact of CAD/CAM on consumerism. Refer to recycling wastage, energy, individual needs and cultural aspects.
E.5.1
E.5.2
Outline how mass customization is transforming the relationship between the manufacturer and the consumer. In mass customization the manufacturer produces products in response to customer orders.
E.5.3
Discuss the impact of mass customization on production systems.
E.5.4
Discuss the advantages and disadvantages of mass customization for manufacturers and consumers.
E.6 Global Communication Systems
E.6.1
State that information is now regarded as a separate commodity which is handled by computers and associated equipment.
E.6.2
Define optical fibre, analogue signal, digital signal, satellite communication and the Internet.
E.6.3
Outline how fibre optics are able to transmit information in large quantities.
E.6.4
Compare the effectiveness of information transfer in optical fibres and copper wires.
E.6.5
Describe how fibre optic technology allows for a wide variety of input and output devices. For example, videoconferencing, televisions and computers.
E.6.6
Discuss the opportunities that fibre optic technology offers to global communications systems.
E.6.7
Outline how satellite systems are able to transmit information.
E.6.8
Describe the opportunities offered by satellite technology for global communications systems. The signals cover the globe; standardization is critically important.
E.6.9
Compare fibre optics and satellite technologies. Consider capacity, reliability, infrastructure, speed, cost etc.
E.6.10
Explain how the Internet can assist designers with market research. Designers can gain access to information without the need to carry out research themselves. The views of experts can be easily sought.
E.6.11
Explain how the Internet can assist designers with design development. Designers can show others their ideas and evaluate their views.
E.6.12
Discuss the implications of the Internet on design protection. You cannot copyright or patent a design once you have shared it with anyone.
E.7.1
Define flexible manufacturing system (FMS), design for manufacture (DfM), design for disassembly and lean production.
E.7.2
Outline the benefits of FMS to manufacturers. It reduces labour, shortens lead times, improves productivity and quality, and reduces costs.
E.7.3
State that DfM can be a dominating constraint on the design brief and that it can be conveniently split into design for materials, design for process and design for assembly.
E.7.4
Explain design for materials. This is designing in relation to materials during processing, rather than designing for the final desired properties of the end product in use.
E.7.5
Explain design for process. This is designing to match an existing manufacturing process, eg injection moulding.
E.7.6
Explain design for assembly. This is designing to take account of assembly at various levels, eg component to component, parts into sub-assemblies, and sub-assemblies into complete products.
E.7.7
Discuss three strategies designers could employ for DfM. Strategies could include minimizing the number of parts, using standard components, designing parts which are multi-functional or for multi-use, designing parts for ease of fabrication, minimizing handling, using standard sub-assemblies, or minimizing component variation.
E.7.8
Discuss two strategies designers could employ to design for disassembly. Strategies could include designing components made from one material, using adhesives that lose their properties easily when reheated, designing snap-fittings instead of welding and gluing.
E.7.9
Compare lean production with mass production. Lean production uses less of everything compared to mass production: less human effort, less manufacturing space, less manufacturing time, fewer defects and less storage of components and products.
E.7.10
The car manufacturer Toyota pioneered lean production in the 1950s to compete with companies such as Ford which used mass production. Workers need to be professionally skilled and must be able to diagnose problems, repair equipment and undertake their own quality control without supervision. They must work well in a team and take responsibility for their work. Describe the implications of lean production for the workforce
E.8.1
Outline the importance of lean production to the global car manufacturer. Lean production allowed Japanese manufacturers to become world leaders, eg in 1950 Ford was mass producing 7000 cars per day and Toyota had only produced 2685 cars in total after 13 years of manufacturing. By 1990 Toyota had become the third biggest car manufacturer in the world by employing lean production.
E.8.2
Explain why global manufacturers from the West have found it difficult to adapt to lean production. Consider constraints of traditional working practices, the views of the workforce, training, costs of new machinery, the challenge of zero defects and a wide variety of products and cultural influences.
E.8.3
Define multi-national (transnational) company
E.8.4
Discuss two reasons for the growth of multi-national companies. Consider mobility of capital ie increased foreign investment, expansion of international trade, worldwide markets (and competition), global manufacturing outlets, reduction in trade boundaries, advertising, rapid communication systems, and international movement of money and people.
E.8.5
Explain why global manufacturers establish production units in different parts of the world. Consider distribution of products, trade agreements, trade tariffs and incentives from governments.
E.8.6
Discuss the advantages and disadvantages for countries of hosting the production units of global manufacturers. Consider imported expertise and technologies, employment, image, their effects on the local and/or national economy, the influence of multi-national companies, and the effect on the environment, culture and working practices.