GCSE Design & Technology Systems & Control: Written Paper

Structure of the Exams

The first paper (paper 2!) will test your knowledge of the core elements of systems and control. The second paper (paper 8, naturally) will test your knowledge of the mechanisms option. Both papers are 1 hour 15 minutes long and each will have five questions, all of which are compulsory. This equates to 15 minutes per question. The questions do get progressively harder but you should obviously attempt all of them.

When answering the questions, please bear in mind the following:

· Words such as 'list', 'state' or 'name' usually indicate that one word answers are acceptable. However, be careful not to give generic answers such as 'cheap' or 'strong'.

· Words such as 'describe' and 'analyse' usually require a more detailed, structured answer.

· If you are asked to draw a diagram then draw one! Add clear annotation (labels) where required.

· The marks allocated for each part of the question are a good guide to the amount of detail needed in the answer.

· The number of lines or the amount of space is another clue as to the level of detail required.

· A product analysis question will always ask you to apply your knowledge to the wider effects of design and technology on society.

· Spelling is not crucial but legibile hand-writing is.

· Remember to use the knowledge that you have now gained from doing the coursework.

The following titles are the main Core topics which will form the first written paper.

Whilst many of the statements are a reflection on what you have done as part of your coursework, you might be asked questions about them. Make sure that you understand all the different terms used.

Developing a design brief

Drawing up a specification:
· Intended purpose of product
· Consideration of existing products
· Data relevant to users such as anthropometric data
· British and European standards i.e. ISO, BS, EN, DIN, CE mark.
· Environmental and monetary costs

Generating design proposals:
· Record ideas using combination of text and graphical techniques
· Evaluation of design ideas against specification
· Relevance of function, ergonomics and aesthetics
· 2D and 3D modelling
· Use of CAD to generate, develop and model ideas

Product Development:
· Testing and trialling to make decisions
· Consider possibilities and implications for batch production and prototype

Product Planning:
· Prepare materials economically allowing for waste
· Use pre-manufactured components
· Consider Health & Safety issues

Tools and Equipment:
· Correct use of marking-out and checking tools – try square, callipers, scriber, centre punch, multimeter
· Cutting and machining tools – saws, files, drills etc
· General tools – screwdrivers, soldering irons, wire-cutters, strippers, pliers, spanners
· Finishing materials – abrasive papers, appropriate finishes for materials and their purpose
· Correct tools/equipment for shaping, forming and joining – matching tools and equipment to the materials and processes, vac former etc
· Jigs and Formers – repetitive operations such as drilling holes
· Safe working practices

Processes:
· Select a range of appropriate construction and production methods – PCB production, soldering, fabrication, component assembly
· Work with plastics using wasting, shaping and fabricating techniques – injection moulding, vacuum forming, strip bending
· Work with wood/metal using wasting, shaping and fabricating techniques – sawing, filing, drilling and an understanding of machine wasting
· Select and apply appropriate finishes and markings – labelling, varnish, dip-coat and commercial plating
· Select and use appropriate adhesives – PVA, contact, epoxy, tensol cement

ICT Applications:
· Understand how CAD/CAM is used in industrial manufacturing
· Understand how computer systems can control machines and equipment
· Understand how CAD/CAM is used in the manufacture of single items and small batches
· General use of ICT for desktop publishing, spread-sheets, bar charts, pie charts, graphics etc.

Industrial Applications:
Production Methods
· Job Production – one off
· Batch Production – specified quantity
· Repetitive Flow – large numbers of identical products for a relatively low cost. Production broken into sub-assemblies
· Continual Flow – uninterrupted 24/7 production of basic commodities such as oil, steel or basic food products
Manufacturing Systems
· Cell Production – a number of work stations grouped to produce a single product
· In-line assembly – used to mass produce everyday items such as cars. Often fully automated
· Just-in-time – components arrive from outside sources as they are required on the production line
· Logistics – production of a product relies upon the availability of materials and components when required

· Packaging, marketing and advertising – information, legal requirements, storage, cultural
· Importance of control to ensure a quality product - ISO 9000, quality control

Good Working Practice:
· Produce process and block diagrams – order for work, sub-tasks
· Produce time plans

Product Evaluation:
· Review work to check quality
· Evaluate the product against its fitness for purpose, the design need, the needs of the intended user, cultural and environmental issues
· Testing and modification, proposals for further development

Materials
· Timber, metals, plastics, composites and ‘Smart’ materials: their forms, applications and uses.
· Properties - ductility, hardness, malleability, toughness, strength (compression, tension, shear) etc.

Components
· Select appropriate electronic, mechanical and pre-manufactured components

Energy
· Storage and forms of energy;
· Primary – solar, wind, hydro, fossil fuels, nuclear
· Secondary – springs, batteries, rubber bands, compressed air
· Benefits/drawbacks of different sources

Electronics
· Give examples of conductors and insulators
· Use circuit symbols and correct formulae and units, V=IxR, P=IxV
· Designing simple circuits using different input sensors (light, temp, moisture) and output devices (lamp, motor, solenoid)
· Use of different switches SPST, SPDT, DPDT, NO, NC.
· Use of a diode as a one-way conductor
· Use of LED’s, transistors and current-limiting resistors


Mechanisms and Structures
· Man-made and natural structures
· Load, effort, fulcrum and calculations of moments
· 1st, 2nd and 3rd order levers and linkages
· Frames, triangulation and stiffening structures with gussets, ribs and laminating
· Calculating gear ratios and transmission speed
· Different types of motion – rotary, linear etc.
· Cranks, cams and followers

Products and Applications
It is expected that you are able to analyse a commercially manufactured product and:
· Establish the design criteria and function of the product
· Identify how the constituent parts and how the product works
· Identify the materials and manufacturing processes used to make the product

Quality
· Difference between quality of design and quality of manufacture
· Quality control
· Judging how well a product meets the needs of the user
· Importance of accuracy
· Appropriate use of resources
· Selecting the correct finishing process for aesthetic and functional reasons
· Social, moral, economic, environmental and aesthetic implications

Health and Safety
· As designers and consumers – correct selection of materials, product function
· As workers within the production environment – storage/usage of tools and equipment, chemicals, solvents, flammable and toxic substances
· Personal Safety – protective overalls, safety goggles, machine guards, dust and fume extraction, disposal of waste
· Risk Assessment – COSHH, recognition of instructions and safety symbols
· Environmental effects – disposal of chemicals, reduction in the use of environmentally damaging chemicals i.e. bleaches, CFCs, toxic materials

GCSE Design & Technology Systems & Control: Mechanisms Option

NB. The following list contains topics for the Mechanisms option paper that are additional to those listed above under ‘Mechanisms and Structures’

Transmission of Motion
· Selecting the most appropriate gears – spur, bevel, helical, worm, contrate, crown wheel, rack and pinion
· Flat, toothed, and vee belts and pulleys, cone pulley, sprockets and chain, splined shafts, universal joints, plain and flexible couplings
· Maintaining tension in drive belts
· Calculate driver/driven speeds and work out direction
· Mechanical Advantage (MA), Velocity Ratio (VR) and efficiency of simple machines
· Screw jacks, compound pulleys and gears

Bearings and Lubrication
· Plain, roller and ball bearings
· Different types of lubrication

Conversion of Motion
· Dwell and stroke for cams
· Describe/select appropriately crankshafts, crank/slider, rack and pinion, ratchet and pawl, eccentric and simple cam mechanisms

Control of Motion
· Function of brakes, comparing effectiveness of hydraulic, cable, disc and drum brakes
· Function of clutches, uses of single plate, dog and centrifugal clutches

Energy

. Power sources used to drive mechanisms, energy costs involved