DT Flashcards
(193 cards)
1
Q
Iterative design
A
a cyclic approach: each iteration of a design is tested and then altered accordingly
2
Q
iterative design advantages
A
- each iteration is fully tested/evaluated so issues will be discovered and fixed earlier
- it encourages focus on the most critical aspects of a design
- user feedback is constantly gathered
- evidence of progress is easily provided to stakeholders
3
Q
Iterative design disadvantages
A
- it can be time consuming
- it can be expensive to make so many iterations?
- designers can lose site of the bigger picture when focusing on an iteration
4
Q
User centred design
A
the needs and wants of a user are considered extensively at each stage of the design process.
5
Q
user-centred design advantages
A
- The end user feels listened to and is more likely to be satisfied with the product
- the user feels a greater sense of ownership of the product due to input
6
Q
user-centred design disadvantages
A
- it requires extra time to meet/discuss with the client and then alter the design
- It can become focused on one specific person: it is then unavailable to sell to the wider population
7
Q
Systems thinking
A
a top down approach that starts with an overview of a product in terms of : input, process and output. The details of each component are considered later.
- often used in electronic/mechanical systems
8
Q
Systems thinking/approach advantages
A
- does not require specialist knowledge to design system overview
- this approach is easy to explain / communicate to non-specialists e.g. clients/stakeholders
- The system is designed in blocks so it is easier to discover faults in the design
9
Q
Systems thinking/approach disadvantages
A
- it can lead to the use of unnecessary components
- this can lead to larger systems and extra cost
10
Q
Structure of a system
A
input device –> process –> output device
input devices take a’real world’ signal e.g. light/movement/sound and turn it into an electronic signal.
Output devices take this electronic signal and turn it into a real world signal e.g speakers produce sound and lamps produce light
11
Q
CIRCUIT SYMBOLS
A
P.11 revision guide
12
Q
Microcontrollers
A
a small computer or an integrated circuit that can be programmed to provide functionality, timing counting and decision making.
- process
13
Q
push to make switch
A
allows current to flow through when pressed
- input
14
Q
LDR
A
a resistor that changes depending on light level
- input
15
Q
buzzer
A
produces a buzzing noise when current flows through it
- output
16
Q
speaker
A
turns electronic signals into sounds
- output
17
Q
lamp
A
produces light when current flows through it
- output
18
Q
Apple (The Work of Others)
A
- multinational consumer electronics company
- initially solds personal computers such as the Macintosh
- later they introduced the aesthetically iconic iMac G3, portable iPod and the iPhone.
- The iPhone combined components of the iPod and the G3.
19
Q
Primark (the work of others)
A
- international clothing retailer
- low cost, fashionable products
- produces clothes in factories in china, bangladesh, india etc.
- fast fashion contributor
20
Q
Zara (the work of others)
A
- uses a Just in time approach (JIT)
- began working with Greenpeace in 2011 to eliminate harmful toxins from its clothing
21
Q
Deforestation
A
forests are removed so land can be used for other uses. this causes:
- loss of habitat
- increased CO2 levels
22
Q
Mining
A
some raw materials must be mined from the ground e.g. metal ores. This causes:
-erosion
- contamination of soil
- visual pollution
- loss of habitat
- non renewable
23
Q
Drilling for oil
A
- non renewable
- oil spills are detrimental to the local area
24
Q
Things to consider when designing a product (environmental) (x6)
A
- obtaining raw materials
- distance/mileage to place of manufacture
- manufacture
- distribution
- use
- disposal
25
The 6 Rs
Refuse - should it be produced?
Rethink - what can be changed (e.g. less packaging)
Reduce - use less/produce less
Reuse - use it again
Repair - fix instead of repurchasing
Recycle - reuse materials
26
Fair Trade
A movement that works to aid people in developing countries in receiving a fair wage for the products that they produce
- producers are paid an agreed minimum rate even if global prices fall
27
Market research
the collection of information to find out gaps in the market, client requirements, price etc.
28
focus group (what and why)
- a focus group is a group of people that match the target user group: ideally 7-10 people. This to ensure a range of opinions/feedback however if it is too big, people may not all be able to share their ideas.
29
product analysis
the detailed investigation or analysis of current or previous products. Aspects considered include:
- aesthetics
- function
-price
- societal impact
- environmental impact
30
Primary data
firsthand data / original research e.g. a questionnaire produced by the designer themselves
31
secondary data
freely available data that is taken from other sources e.g. available data sheets
32
Ergonomics
Human factors: involves how the user interacts with the product.
ergonomic factors include safety and comfort.
33
Anthropometrics
The study of the human body and how it moves.
Anthropometric data is taken from millions of people to create well suited products e.g. a helmet uses average head circumferences, doors use average heights etc.
- Designers often work with 5th to 95th percentile
34
Design brief
a short description of the design problem and how it is to be solved
35
Design specification
a list of measurable design criteria that the product must meet.
A good specification should include:
ACCESS FM :
- Aesthetics
- Client
- Cost
- Environment
- Safety
- Size
- Function
- Materials
36
Manufacturing specification
contains the information needed to successfully manufacture the design.
It should include :
- scale of production (e.g. batch/mass etc.)
- description and/or drawing of final design
- assembly and construction details
- details of materials needed
- how quality will be ensured
37
Freehand sketching (uses/pros/cons)
uses: getting initial thoughts onto paper
pros:
- does not follow conventions so can be done quickly and freehand
cons:
- needs to be followed by a more formal design
38
modelling (uses/pros)
use: to gain insight on how a product will look and function in 3D. This is often done with card because it is cheap, easy to cut, crease and fold.
pros:
- can be presented to clients for feedback
cons
- issues can be found and sorted early before the use of more expensive materials
39
Toiles
a test version of a piece of clothing made from cheap material
- used to check the effectiveness of a sewing pattern
- design can be improved without wasting expensive material
40
Breadboarding circuits
Breadboards consist of rows of metal strips, covered by plastic holes.
Components and wires are placed into these holes to form a circuit.
- circuits can be quickly tested
- components can be reused
- better than CAD since it uses real components: software is not always accurate in predicting problems.
- temporary model, a more permanent construction method should be used for the final product.
41
3D sketching
can be produced by: freehand, perspective or by isometric projection. It creates a realistic view of a product e.g. to show to clients.
- The drawing is not to scale
- has a horizon line
- one or two vanishing points sit on the horizon line
42
Exploded drawings
These show how components fit together, the parts should be lined up and in proportion to the other components of the drawing.
- often used in furniture assembly instructions
43
Orthographic drawings
- Third angle orthographic projection (plan, front and side)
- to scale
- follow conventions
44
PRACTICE ORTHOGRAPHIC DRAWINGS
!!!
45
schematic diagrams
represents the elements of a system using standard symbols, they show which components are linked together
- often used in circuits
46
Virtual meeting software
Allows face to face meetings to take place from various locations.
- no wait time for responses
- visuals can be shared
- no misinterpretation as there is with text/email
47
CAD uses
CAD:
- drawing / modelling / simulating ideas
- designs can be viewed from all angles
- CAD files can be directly sent to CAM
- CAD files are easily shared: email, USB etc.
48
Prototypes
- full sized, actual versions of a product
- used to check aesthetics and functionality
- ensures money is not wasted on large scale manufacture if there is an issue
49
Evaluating prototypes
CAFE QUE :
Cost
Aesthetics
Function
Ergonomics
Quality
User
Environment
50
Fossil Fuels
- inc. coal/oil/natural gas
- They are burned to create steam which turns turbines which drive generators that produce electricity
- releases greenhouse gases e.g. CO2 (contributes to global warming)
- reliable
- non-renewable
51
Nuclear Power
- Nuclear Fission
- Non Renewable (Uranium)
- If radioactive material is released, it can cause serious health issues
- Nuclear waste must be disposed of carefully and stored for thousands of years
52
Solar Power
- Photovoltaic cells convert solar energy into an electric current
- renewable
- no waste products
- unreliable
- high initial cost, but no ongoing cost
- converts less than 10% of sunlight
53
Wind power
1. wind turns the turbine
2. the turbine turn the generator
3. the generator produces electricity
- unreliable
- renewable
- visual and sound pollution
54
hydro-electrical
1. water is held in a reservoir behind a dam
2. the water is released downhill, this turns turbines as it goes
- renewable
55
Biomass fuel
- fuel from organic materials
- readily available
- can be expensive
- can drive up prices of food
- CO2 to grow the fuel
56
storing energy
- batteries: transfers chemical energy into electrical energy
- kinetic pumped water storage
57
4 types of motion
reciprocating
linear
oscillating
rotating
58
rotating motion
movement in a circle
59
linear movement
motion in a straight line in one direction
60
reciprocating motion
back and forth motion
61
oscillating motion
swinging back and forth motion
62
Levers function
to reduce the amount of effort required to move a load
63
first order lever (mechanical advantage and examples)
- fulcrum in the middle between effort and load
- there is mechanical advantage if the effort is further from the fulcrum than the load
e.g. scissors, seesaw
64
mechanical advantage second order lever (and example)
- Load in the middle between effort and fulcrum
- there is always a mechanical advantage because load is closer to the fulcrum than effort
e.g. wheelbarrow
65
Linkages
- used to transfer motion between two positions
66
third order lever (mechanical advantage and example)
- effort in the middle between fulcrum and load
- no mechanical advantage: effort is greater than the load HOWEVER movement of load is greater
e.g. tweezers
67
push-pull linkage
reverses the direction of linear motion
- 2 moving pivots, 1 fixed
PRACTICE DRAWING THIS
68
bell crank
changes the direction of motion by an angle
- 2 moving pivots, 1 fixed
PRACTICE DRAWING THIS
69
cams
convert rotary motion to reciprocating motion
70
follower meaning
- a rod that is moved as the cam rotates
- normally connected to the object that wants moving
- followers can: rise, dwell or fall
71
Graphene
one layer of carbon atoms
- very strong (200x stronger than steel)
- electrical conductor
- very lightweight
uses:
- drug delivery
- mobile technology (touch panels)
- solar cells
72
eccentric circle - shaped cams
smooth but significant rise and fall of the follower
73
pear-shaped cams
idle halfway and then a gentle rise and fall
74
snail-shaped cams
- The follower remains stationary before gently rising then suddenly falling
- only works in one direction of rotation
75
heart shaped cams
rises and falls with uniform velocity
76
gears : how do they work
- gears have teeth that mesh together with other gears
- gears that work together must have the same sized teeth
- the size of a gear determines its speed of rotation
- gears change the direction of motion
76
spur gears
transfer rotary motion
76
bevel gears
transfer rotary motion through 90 degrees e.g. in hand drills
77
worm and worm wheels
- change rotary motion through 90 degrees
- causes a very large reduction in speed
- provides a high torque
78
rack and pinion
- converts between rotary and linear motion e.g. in car steering
79
pulleys
- a pair of grooved wheels with a belt running in the groove
- they transfer rotary motion
- the size of the wheels means the force and speed of motion can be changed
- if the belt is too loose or the force being transmitted is too high, the belt will slip and the motion will not be transferred
80
open belt pulley
the wheels run in the same direction
81
crossed belt pulley
the wheels run in opposite directions
82
strength
the ability of a material to withstand a constant force
83
elasticity
the ability of a material to return to its original size/shape after being deformed, once the force is removed
84
ductility
- the ability of a material to be drawn into wires
- the ability of a material to be permanently stretched or deformed when a force is applied
85
malleability
the ability of a material's shape to be permanently changed by a force without cracking or breaking
86
hardness
the ability of a material to resist wear or being scratched
87
toughness
- the ability of a material to resist a sudden force
- also known as impact resistance
88
tension
- a pulling force from each end
89
compression
- a pushing force from each end
- a squeezing force
90
torsion
a twisting force
91
shear
two parallel forces in opposite directions to each other
92
density
mass per unit of volume
93
thermal conductivity
- the ability of a material to allow heat to pass through it
- measured in W m^-1 K^-1 / watts per metre per Kelvin
94
electrical conductivity
- the ability of a material to allow electricity to pass through it
- low electrical conductivity = high resistance
95
absorbency
the ability of a material to draw in moisture
96
fusibility
- the ability of a material to be changed from a solid to a liquid by heat
- this is important for welding or soldering
97
tensile strength of: timbers, metals, thermoforming polymers, thermosetting polymers
- timbers: Low
- metals: high
- thermoforming polymers: low to medium
- thermosetting polymers: medium to high
98
compressive strength of: timbers, metals, thermoforming polymers, thermosetting polymers
- timbers: medium
- metals: high
- thermoforming polymers: low to medium
- thermosetting polymers: low to medium
99
hardness of: timbers, metals, thermoforming polymers, thermosetting polymers
- timbers: low
- metals: high
- thermoforming polymers: low to medium
- thermosetting polymers: medium
100
toughness of: timbers, metals, thermoforming polymers, thermosetting polymers
- timbers: medium
- metals: high
- thermoforming polymers: low to medium
- thermosetting polymers: medium
101
malleability of: timbers, metals, thermoforming polymers, thermosetting polymers
- timbers: low
- metals: high
- thermoforming polymers: high
- thermosetting polymers: low
102
ductility of: timbers, metals, thermoforming polymers, thermosetting polymers
- timbers: low
- metals: medium / high?
- thermoforming polymers: high
- thermosetting polymers: low
103
layout and tracing paper properties
- relatively hard
- translucent
- typically 50-90 gsm
104
layout and tracing paper uses
- tracing
- working drawings
105
bleed-proof paper: properties and uses
- smooth
- relatively hard
- resistant to ink and colour seeping through: this allows clear and sharp images
- typically 70-150 gsm
- printed flyers and leaflets
106
cartridge paper: properties and uses
- tough
- lightly textured
- typically 100-150 gsm
- drawing/painting
- printed flyers / leaflets
107
grid paper
- printed square and isometric grids
- 60-100gsm
- model making, quick sketches
108
corrugated cardboard
- contains 2 or more layers of card with interlacing fluted inner sections
- often made from recycled materials
- low cost
- 250gsm upwards
- packaging e.g. pizza boxes
- impact resistance
- insulative
109
duplex board
- white surfaces with grey fibres in between
- lower cost than fully bleached card
- 230-420 gsm
- food packaging
- printable
110
foil-lined board
- aluminium foil is laminated to one side of carboard/solid white board / duplex board
- insulative
- drink cartons, ready meal lids
111
foam core board
- paper surfaces covering polystyrene centre
- 1.5 - 12 mm thick
- architectural models
- mounting of pictures
112
solid white board
- strong
- made from pure bleached wood pulp
- 200-400gsm
- expensive packaging, book covers etc.
113
inkjet card
- strong
- often coated
- 240-280 gsm
- printing with inkjet printers : greetings cards, business cards
114
stock forms : paper
- sheets or rolls
- sheets range from A0 (largest) to A6 (smallest)
- printer paper is usually A4 or A3 and around 80gsm
- typically card is 200gsm+
115
stages of manufacturing paper
1. trees are chopped for wood
2. the wood is debarked
3. the wood is chopped and mixed with chemicals to turn it into a pulp
4. chemicals like chalk and die are added to bleach the paper
5. rolled onto mesh through rollers
6. left to dry
7. cut to size
116
hardwood
- typically comes from deciduous trees
- Oak, Birch, Ash, Mahogany, Blalsa
117
Oak
- hardwood
- hard and strong but easy to work with
- open grained
- used for high quality furniture
118
Birch
- hardwood
- hard but easy to work with
- close, fine grain
- furniture and cabinets
- turned items
119
Ash
- hardwood
- tough and flexible
- open-grained
- tool handles, sports equipment, wooden ladders
120
mahogany
- hardwood
- strong and durable
- some interlocking grain
- high quality furniture
121
Balsa
- hardwood
- soft : can be marked using a finger
- modelling
122
softwoods
- come from coniferous trees
- typically have needles instead of leaves
- pine, larch, spruce
123
pine
- softwood
- fairly strong and durable but easy to work with
- furniture, construction work and joinery
124
larch
- softwood
- tough and durable
- water resistant
- boats and yachts, exterior cladding of buildings, interior panelling
125
spruce
- strong and hard, but low decay resistance
- general construction, wooden aircraft frames
126
stock forms: wood
- planks
127
MDF
- medium-density fibreboard
- made from particles of timber mixed with a bonding agent or glue and compressed
- smooth surface
- furniture, interior panelling
128
plywood
- constructed from layers of veneer or plies
- furniture making, marine plywood is used for boat building
129
chipboard
- made from coarse particles of timber, mixed with a bonding agent or glue and compressed
- rough surface / uneven texture
- often covered with a laminate
- kitchen worktops
130
ferrous metals
- these are metals that contain iron
- melting point of 1600 degrees celsius or higher
131
cast iron
- ferrous metal
- hard
- good compressive strength
- poor tensile strength
- brittle under tension
- uses: engine blocks, cookware, piping
132
low-carbon steel
- ferrous metal
- tough
- relatively low cost
- prone to corrosion
- uses: car body panels, nuts and bolts, engine parts
133
high-carbon steel
- ferrous metal
- very strong and hard
- more brittle and less ductile than low-carbon steel
- uses: springs, high-tension wires
134
non-ferrous metals
metals that do not contain iron
135
how to separate ferrous and non-ferrous metals
- ferrous are magnetic but on-ferrous aren't
136
aluminium
- non-ferrous metal
- lighter than steel
- less strong than steel
- uses: drinks cans, pans, food packaging
137
copper
- non-ferrous metal
- excellent conductor of both heat and electricity
- electrical wiring, water pipes
138
tin
- non-ferrous metal
- relatively soft and malleable
- excellent corrosion resistance
- uses: to plate steel/coating steel cans for corrosion resistance, tin cans
139
zinc
- non-ferrous metal
- hard
- brittle
- malleable between 100-150 degrees
- relatively low melting point
- uses: a coating on steel (galvanising) to improve corrosion resistance, anode in alkaline batteries
140
brass
- copper and zinc alloy
- corrosion resistant
- malleable
- uses: locks, musical instruments
141
stainless steel
- iron and chromium with a small amount of carbon alloy
- tough, strong and hard
- corrosion resistant
- uses: kitchen equipment, medical instruments
142
high-speed steel
- iron with small amounts of tungsten, carbon, molybdenum, vanadium and chromium alloy
- very hard even at high temperatures
- strong
- brittle
- low ductility
- uses: power saw blades, drill bits, files, chisels, woodturning tools
143
stock forms: metals
- sheets
- rods
- round/square bars
- tubes
- it takes a lot of energy to reform metal so designers try to use standard shapes and sizes
144
making polymers
- manufactured from carbon-based fossil fuels like crude oil
- hydrocarbons from crude oil are broken down through cracking
- polymers are then made through addition or condensation polymerisation
- they are a finite resource
- synthetic polymers are usually not biodegradable
145
thermosetting polymers
- cannot soften when heated
- commonly available as liquids like resin or powders
- they typically are disposed of in landfill
146
types of thermosetting polymer
- epoxy resin
- polyester resin
- urea formaldehyde
147
thermoforming polymer
- also known as thermoplastics
- soften when heated and can be shaped when hot
- they cool and harden in the new shape but can be reheated to change the shape again
148
thermoforming polymer examples
- polyethylene erephthalate (PET)
- high density polyethylene (HDPE)
- PVC (polyvinylchloride)
- HIPS (high impactv polystyrene)
- PP (Polypropylene)
- PMA
149
natural fibres
- come from plants or animal s
- wool, silk, alpaca, cashmere
- cotton, linen, jute, hemp etc.
- they are biodegradable
150
metal foams
- made from metal containing gas-filled pores
- they look like sponge made from metal
- physical properties of metal but up to 95% lighter
- used for crash resistant structures in vehicles and sound damping
151
nanomaterials
- made up of particles less than 100 nanometres in size
- uses: coatings for glass and fabrics can repel dirt or water
152
smart materials
- they have a property that changes in response to external stimulus, this change is reversible if the external stimulus changes again
- the external stimulus could be: temperature, light, pH etc.
- these include thermochromic pigments and photochromic pigments
153
composites
- combines the properties of 2+ materials
- unlike an alloy, the materials are not chemically bound
- examples: GRP, fibreglass, carbon-reinforced polyester
154
technical textiles
- manufactured for performance properties rather than aesthetics
155
standard components
- parts can be bought in bulk and used across various projects / products
- the process can be automated
- allows them to be bought at lower costs
156
standard components used with papers and boards
- bulldog clips
- bindings
- paperclips
- plastic rivets
157
standard components used with timber
- hinges
- brackets
- screws
- nails
- handles
158
standard components used with polymers
- caps
- fasteners
- nuts, bolts and washers
159
standard components used with fabrics and fibres
- zips
- buttons
- velcro
160
standard components used with metals
- nuts and bolts and washers
- rivets
- hinges
161
standard components used with electrical circuits / components
- resistors
- bulbs
- diodes / LEDs
- microcontrollers
- switches
- motors
162
standard mechanical components
- levers
- linkages
- gears
- cams
- pulleys
- belts
163
purpose of finishing materials
improving function or aesthetics e.g. creating a shine or a barrier
164
finishes on metal based materials
- dip coating: forms a smooth finish
- powder coating
- galvanising: steel dipped in molten zinc
165
finishes for polymers
- polishing
- vinyl decals can add lettering or decoration
- printing
166
finishes for timbers
- painting
- varnishing
- tanalising: pressure treatment used to preserve wood
167
textile finishes
- block and screen printing
168
paper and board finishes
- printing: screen printing, offset lithography, flexography
- embossing
- UV varnishing
169
factorsw to consider when choosing materials
- aesthetics
- environmental considerations
- availability/accessibility
- cost
- social factors
- ethical factors : e.g. fair trade
- cultural factors e.g. fashion
170
methods of reinforcement
- webbing
- interfacing: adding extra layers of material to a textile product to increase the strength - often used in shirt collars
171
one-off / bespoke production
- one product made at a time
- this could be personalised or a prototype
- the cost of each product is high
172
batch production
- a small group of identical products are produced
- producing a limited number of identical products - each item in the batch passes through one stage of production before passing on to the next stage
173
mass production
- the efficient production of large numbers of identical goods through a manufacturing line
- most processes are automated
- the equipment is used again and again to produce the same products
174
continuous production
- large quantities of identical products are made continuously, used for commodities
- typically fully automated processes
- initial set up cost is high but cost per product made is much lower than other methods
175
wastage
the removal of unnecessary/unwanted material when making a product
176
wasting processes with papers and boards
- cutting with scissors
- tearing
- perforation cutters
- die cutters
177
addition processes with papers and boards
- printing
- embossing
- laminating
sticking together with adhesives
178
tools that improve accuracy
- patterns
- templates
- jigs
- CAD / CAM
179
tolerance
- the permissible limits of variation in the dimensions or physical properties of a product
- represented as +- x%
180
crowd funding
- many people give small investments to a project or idea
- this results in large funding overall
- this is low-risk for investors
- if one investor pulls out, it is not a huge problem
181
virtual marketing
the use of social media or web-based marketing techniques
182
co-operatives
- a company run jointly by the members of it
183
planned obsolescence
- a product is designed to no longer be useful after a certain amount of time
- this could be in terms of functionality, fashion or compatability
184
advantages of CAD
- More accurate than hand-drawn designs
- less storage space needed
- 3D models can be viewed from all angles
- designs can be exported to CAM
- makes sharing designs easy
185
CAD disadvantages
- high initial costs
- requires specialist training
186
CAM advantages
- consistency: every product is identical
- great efficiency
- less employees need to be paid
- increased speed of manufacture
187
CAM disadvantages
- high initial costs
- highly trained specialists required
- can reduce jobs
- slower for one off / bespoke products
188
lean manufacturing
- aims to eliminate all forms of waste
- JIT (just in time) production: materials are supplied only when needed / no stockpiling or storing in warehouses
189
JIT disadvantages
- easily delayed if the materials are not delivered on time
- expensive material can end up not being used
- deadlines can easily be missed
190
technology push
new products are produced due to new technology becoming available
191
market pull
new products produced due to demand from users
