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A systems approach

•A systems approach is where you break down the stages of a process into a series of steps.

•Systems have three sections. They are connected together so they make a product function:

INPUT PROCESS OUTPUT

INPUT DEVICES

•Light sensor

•Temperature sensor

•Pressure sensor

•Switches

PROCESSES

•Microcontrollers

•PICs

•Timers

The are basically programmed components that make decisions within a circuit so the circuit knows what it needs to do!

OUTPUT DEVICESWe know that electronic systems have three sections: input, process and output.

The input is processed into an electronic signal, which then makes the output device work.

Examples of OUTPUTS are:

•Speakers

•Buzzers

•Lamps

•LEDs (Light emitting diodes)

FORCES and STRESSES

•All materials need to be able to withstand a variety of forces and stresses.

•A force is a load that has been applied.

•It is measured in newtons (N).

•As the load is applied to a material, it produces a stress. This may cause the material to deform (bend).

COMPRESSION

TENSION

BENDING

TORSION

SHEAR

FORCES and STRESSES

COMPRESSION TENSION BENDING TORSION SHEAR

FORCES and STRESSES

BENDING•This force creates tension and compression.

TENSION•This is a pulling force.

COMPRESSION•This is a force pressing onto a material.

LOAD

FORCES and STRESSES

TORSION•This is a twisting force, often along the length of the material.

SHEAR•This is when two parallel forces are acting against each other.

METALS AND ALLOYS

•Ferrous metals –contain iron

Non-ferrous –contain no iron

Alloys – a mixtureof two or more metals

DO rust

DON’T rust

CAN rust

TIMBER(and Timber composites)

•Hardwoods from deciduous trees

(slow growing / lose their leaves)

Softwoods from coniferous trees

(grow faster / evergreen/ cheap)

Manufactured boards

(made from wood particles + glue

man-made / cheap)

•Thermoforming plastics(can be reheated and moulded)

•Thermosetting plastics(cannot be reshaped)

POLYMERS (Plastics)

NAME WHAT IS IT USED FOR?

Mild Steel

Nuts, bolts, washers, car bodies, panels for cookers, appliances

etc.

Medium carbon steel

Springs, general gardening tools

High carbon steel

Hand tools, scribers, dot punches, chisels,

plane blades.

Cast ironMachine parts, brake

discs, engines

FERROUS METALS

METAL COMMON USES AND PROPERTIES

AluminiumKitchenware, power cables, drinks cans,

aircraft bodies.

Copper Electrical contacts, electrical cable and wire

Gold Jewellery, electrical contacts

Lead Soft but heavy metal, used on roofs, durable

PlatinumPrecious metal used in jewellery, but also to

make wires

Silver Cutlery, decorative items, jewellery.

TinUsed to coat steel in food cans to protect it

from rusting

TitaniumSurgical applications (very clean) such as hip

replacements

ZincUsed for coating steel (galvanising), again to

stop air or water getting to the iron in the steel and causing rust

NON-FERROUS METALS

NAME COMMON USES

PEWTER Jewellry

BRASSValves and

taps, ornaments

BRONZE Statues, coins

HARDWOODS

o Come from deciduous trees (lose their leaves)

o Take longer to grow

o Much denser wood (harder/heavier)

o More expensive than softwood

o Available in planks/boards (stock forms)

OAK WALNUT

MAHOGANY CHERRY

BIRCH OAK

SOFTWOODSo Come from evergreen trees (don’t lose their

leaves)

o Quicker to grow

o Cheaper than hardwood

o Available in planks/boards (stock forms)

MANUFACTURED BOARD

o Is man-made

o Made of wood particles and glue pressed together

o Much cheaper than wood

o Available in sheets that come in different thicknesses (stock form)

PLYWOOD

CHIPBOARD

BLOCKBOARD

MDF

Paper and board TRACING

PAPERThin, see through Art work

LINED PAPER Cheap, can be bleached or dyed to any colour

Everydayuse

DUPLEX BOARD Cheap, strong board Cheappackaging

SOLID WHITE BOARD

Expensive, white on both sides

Expensive packaging

FOIL INED BOARD

Cardboard lined with foil (waterproof)

Drinks

CORRUGATED CARD

Two layers of cardwith flutes in between. Good protector/insulator

Product packaging

Smart materials can think for themselves, and react to their environment, and change their properties.

Shape memory alloys change to their original shape when they are heated / cooled. Uses include spectacle frames, dental braces

Thermo-chromic pigments can change colour depending on the temperature they are exposed to. Uses include Flexible thermometers, Babies bottles and cutlery etc

Photo-Chromic pigments alter depending on light intensity. Uses include lens in glasses, signage,

Smart Materials

NATURAL FIBRES

Natural fibres are renewable fibres that come from plants and animals.

Because they are natural, it makes them suitable for clothing.

They have properties such as:

MODELLING

Models are used by designers so they can test out their ideas before they make a final prototype.• It allows them to get ideas of the aesthetics.• They can get customer feedback on modifications• It is cheaper than using expensive final materials.• They can be easily developed.

Modelling materials include:•Cardboard•Styrofoam•Balsa wood•Calico (a natural cotton)

PLANNED OBSOLESCENCE

Some products are designed to have a short life span. Companies plan for their products to become obsolete (run out).They do this by:• Choosing parts that may not last very long• Release upgraded versions• Launch new products to replace old ones.

PLANNED OBSOLESCENCECustomers are encouraged to buy new products, even though they shouldn’t need to. This leads to:• Wasted materials and resources• More pollution/waste/landfill

EFFICIENT WORKINGEfficiency is how quickly you can make something, compared to how long you think it should take. Better efficiency means saved money and energy.

Better efficiency can be achieved by:• Lean manufacturing• JIT production• Improved transport systems• Efficient factory layout

This type of manufacturing helps achieve

EFFICIENT WORKING

LEAN MANUFACTURINGThis is a method used to get rid of waste throughout the manufacturing process. It includes:• Having minimal storage – so materials only

delivered when orders are placed• Making sure production is well set up so there are

no delays• Reducing the amount of materials needed• Using labour efficiently.

FLEXIBLE MANUFACTURING

Flexible Manufacturing Systems (FMS) means delivering expensive products

as quickly as possible (eg. cars).

This type of manufacturing helps achieve

EFFICIENT WORKING

FLEXIBLE MANUFACTURING

• Systems are effective (so they work well)

• Machinery is grouped together (to be more efficient)

• Computers are used to speed up processes.

• Close relationships with suppliers allow fast delivery.

JUST IN TIME (JIT)

JIT helps companies meet orders quickly and minimise time.New stock is only ordered when needed so storage space isn’t wasted.It means that:• Materials/components are in the

right place at the right time• Storage costs are reduced• Production is cost effective

• A break in the supply chain can cause delays

This type of manufacturing helps achieve

EFFICIENT WORKING

Non renewable energy sources are sources that will eventually run out.

The main examples are:

• FOSSIL FUELS

• NUCLEAR POWER

Renewable Energy Sources

Renewable energy sources are SUSTAINABLE and will not run out. They are sources that can replenish themselves. Examples include solar, wind, hydro electrical, biomass and tidal sources.

Renewable Energy Sources

Disadvantages include…

Renewable Energy Sources

Disadvantages include…

Turning Oil into Plastic

1. Oil is basically dead sea plants and animals that have fossilised and broken down.

2. We build oil rigs in the sea so we can get to the oil

3. This is done by drilling down to where the oil is, and bringing it up to the surface.

4. The oil is shipped to shore on an oil tanker

5. It is then sent through a pipeline to the oil refinery.

6. The refinery then cleans (refines) the oil, and turns it into different types of polymer granules.

7. These granules are then sent to a manufacturing plant (factory) to be made into sheets of plastic, or into plastic products.

Turning Ores into Metal

Iron ore, coke and limestone go IN to the blast furnace

Pure molten iron OUT

Impurities OUT

Extraction by carbon reduction

Turning Trees into Wood

CONVERSIONThis is when the tree trunk is sawn along its length into planks.

SEASONINGThis when the planks of wood are dried out to reduce moisture. This can be done naturally or in a kiln.

Turning Trees into Paper

ETHICAL CHOICESBIODEGRADABLE PACKAGING

ETHICAL CHOICESFAIRTRADE COTTON

ETHICAL CHOICES

RECYCLED COMPONENTS

What does

Sustainable mean?

It means being as environmentally

friendly as possible, to make

resources last as long as possible.

• Design products that are made

form renewable materials.

• Design products that use as little

energy as possible.

• Buy products made from

renewable materials.

• Don’t buy products that you don’t

need.

• Turn off lights when you leave a

room.

• Use a Bag For Life when shopping.

Properties

This means what a

material HAS and CAN

DO.

For example copper is

heavy, yellowish, is

malleable and is a

good heat and

electrical conductor.

Aesthetic

This means HOW

SOMETHING LOOKS.

Is it pleasing on the

eye?

Does it have a good

shape, style, colour,

texture etc

Anthropometrics

The study and use

of human

measurements

used when

designing products.

Ergonomics

How products and

spaces are

designed to be

EFFECTIVE and

COMFORTABLE.

5th – 95th

percentile

Ignore the extreme

data.

Class the rest as

AVERAGE RANGE.

Use data to design

effective products.

If we are trying to use the least amount of material possible, pieces should be placed right

up against each other

TESSELLATION

DESIGN SPECIFICATION

A design specification is important because it:• Allows a designer summarise

their research in a useful way.• It gives a clear criteria to

work from.• It makes sure the product

meets the customers needs.• It provides a criteria that you

can test models against.• It allows you to evaluate your

final product against it, to see if it has been successful.

MASS PRODUCTION ITEMS

STEEL CAR DOOR

•Steel is bought in rolls (large amounts can be stored.

•The material is press formed into shape.

•This is done by automation (fast and efficient).

•Welding of other parts can also be done via automation.

The following products are all made using mass production. They are suitable for this type of production because:

MASS PRODUCTION ITEMS

POLYMER TOY INSTRUMENT

• Injection moulding is used which means many identical products can be made at low cost.

• Injection moulding means reduced assembly after production.

•This complex shape can be easily produced over and over with injection moulding.

• Injection moulding allows colour to added easily during the production phase.

MASS PRODUCTION ITEMS

NEWSPAPER

•Paper can be bought in large rolls so that designs can be continuously printed.

•Lithography is used to print – it is quick and ensures identical prints.

•Lithography is high quality and cheap.

•Manufacture is totally automated.

MASS PRODUCTION ITEMSFlat pack furniture

•Manufactured board is used, which have an even appearance. This means each piece will look the same.

•C.A.M is used to cut pieces – ensures repeatability.

•C.N.C machines are used to create assembly holes and slots. Using C.N.C ensures accuracy and speed.

COMMERCIAL PROCESSESThe properties of thermoforming polymers mean they can be softened with heat and reformed into different shapes.

Injection mouldingThis process is used to turn polymer granules into specific shapes. It is used on a large scale with high accuracy. It works by• The polymer granules

are melted• The melted granules

are injected (pushed) into the mould

• As it cools it takes the shape of the mould

COMMERCIAL PROCESSESScreen PrintingThis process is used to print images and graphics onto t-shirts.

1. A stencil of an image is placed onto a mesh screen.

2. Ink is poured on top3. A squeegee is used to push

the ink through a stencil and mesh.

4. The ink is pushed through and onto the fabric.

5. The fabric is then left to dry.6. The process is repeated on

the next t-shirt.

LithographyThis process is used to print graphics onto newspaper, leaflets, packaging etc.• Ink goes onto the roller• This roller then

transfers the ink onto the pattern plate

• The inked pattern is transferred onto another roller

• Paper is then passed under this roller and the image is printed onto it.

COMMERCIAL PROCESSES

DesignersM

ARY Q

UA

NT

• British fashion designer.• Famous in 1960’s for youthful ‘mod’

fashion.• Designed the mini skirt and hot pants.• Used geometric shapes.• Encouraged people to dress to please

themselves.• Treated fashion as a game.

NO

RM

AN

FO

STER

• British architect• Designed high tech buildings• His buildings are environmentally

friendly.• They include a lot of glass and steel.• His buildings have a clear structure.• Famous buildings include the Gherkin

and Wembley.

VIV

IEN

NE

WESTW

OO

D

• British fashion designer.• Influential in the 1970’s punk style.• Combined traditional (tartan and

tweed) with historical (corsets) to create modern designs.

• Influential in the New Romantic pop fashion in the 1980’s too.

Designers

COCO CHANEL

• French fashion designer.• Her brand specialises in luxury items.• She challenged the post-war

traditional corset wear.• Instead she used practical designs

with clean lines.• Her clothes included cropped skirts

and the famous CHANEL SUIT.• The clothes were feminine,

comfortable and natural.• As well as clothing the brand designs

fashion accessories and perfumes.

PHILIPE STARCK

• French product designer• He designed furniture as well.• He wanted to create products that were

durable yet fashionable.• His designs were influenced by fashion

and novelty.• His products are ‘over-designed’ and

stylised.• He worked for Alessi in the 1990’s.• His most famous product is the ‘Juicy

Salif’ lemon squeezer.

Step 5

LASER CUTTINGLaser cutters are capable of very accurate work, a laser is used to etch or cut material precisely. Laser cutting is an example of CAM (Computer Aided Manufacture).

Step 1

An Idea is created on a computer using a CAD package like COREL DRAW, the idea is then sent to the laser cutter

Step 2

Material that is being cut or etched is placed on the laser bed (wood, plastic, metal, material) the laser settings are programmed according to material thickness and type

Step 3A vacuum of air hold the material still ready to extract the fumes that are created

Step 4An intense laser is focussed onto the material being cut using a series of mirrors

The laser moves over the material cutting or etching as it goes. Once the process is finished the lid can be opened to remove the parts.

Advantages Disadvantages Uses:

Cuts quickly, accurately, good standard. Can run for hours.

Expensive to buy and maintain. Need the right software and training

To cut parts or full products or basic models in Paper, Card, Plastics, Metals, Glass and various textiles

Laminating involves “layering or covering materials”. By doing this the end product will be improved eg made waterproof , stronger, more flexible etc.

Step 1

Card or paper is put into a plastic laminating pouch making sure there is space around the outside.

Step 2

Once in the pouch the card, paper is passed through a laminator using rollers, this works by heating the pouch as it passes through, it softens the plastic enough so the parts at the edges fuse together to seal in the card / paper

Step 3

The laminated card / paper leaves the laminator and cools.

Advantages Disadvantages Uses:

Cheap , easy to use,relatively fast

Sizes restricted to A sizes, can be slow if doing multiples. Takes time to heat up

To waterproof, to protect, to last longer, easy clean. Gives a glossy finish to card / paper products. Uses are menus – signs etc

LAMINATING (paper)

LAMINATING WOOD

•Laminating is when two or more layers are joined.

•This means a stronger material is created

YOU CAN ALSO REFORM/DEFORM THE LAYERS AS THEY ARE BEING STUCK TOGETHER:

•Adhesives is applied to the layers of wood

•The wood is then placed in a former and clamped up

•Once dried the laminates are glued and set in shape

3RD ANGLE ORTHOGRAPHIC PROJECTION

• This is a style of technical drawing where you can see the plan (birds eye), front and side view of a product.

• They should all line up with each other.

• You must use guidelines, and a 45 line to make sure this happens.

Plan

Front Side / end

3RD ANGLE ORTHOGRAPHIC PROJECTION