Flashcards in Year 1 Deck (54):
1
definition of a prototype?
an artefact fit for the purpose of testing and evaluating
2
why do we prototype?
to evaluate a concept or design
3
what are 4 ways that prototypes are used?
1. Generate ideas
2. user testing
3. communication
4. design validation
4
what are 5 key characteristics for prototyping?
1. Material substitution - with any materials you have to hand
2. workmanship and audience
3. form vs function
4. iteration
5. fidelity of prototypes
5
what is a low fidelity prototype?
a prototype that is sketchy and incomplete, that has some characteristics of a target product but is otherwise simple. usually used in order to quickly produce the prototype and test broad concepts
6
what is a high fidelity prototype?
an interactive prototype that stimulates the real systems or functionality and design details.
7
what are three types of manufacturing?
1. formative manufacturing
2. subtractive manufacturing
3. additive manufacturing
8
what manufacturing process is very similar to 3D printing?
additive manufacturing
9
what are 5 process technologies? (3D printing)
1. material extrusion
2. vat polymerisation
3. powder bed fusion
4. material jetting
5. binder jetting
10
what is material extrusion?
plastic filament is extruded through a nozzle. support material is required if a part overhangs
11
what is vat polymerisation?
usually liquid based. Parts need curing after printing. created layer by layer
12
what is powder based fusion?
either uses a laser or an electron beam to melt and fuse material powder together.
13
what is material jetting?
a printhead dispenses photosensitive material which solidifies under UV light. Built layer by layer. Very expensive manufacturing
14
what is binder jetting?
a liquid binding agent is deposited to join powder particles. layers then bond. can be brittle.
15
what are 4 things to remember when prototyping?
1. be process specific
2. be material specific
3. machine dependant
4. operator sensitive
16
what is part quality driven by in a prototype?
layer resolution
17
without adequate support, what could happen to parts? (4)
1. lack dimensional stability
2. required undesired post-processing
3. look rubbish
4. likely to fail and waste resources
18
what is infill structure and density?
usually a grid of squares or hexagons. Can be used to add structural rigidity to parts.
19
when a lower percentage of infill is used, what does this lead to?
1. speeds up printing
2. reduces the chances of warping
3. saves resources
20
when a lower percentage of infill is used, what does this lead to? (3)
1. speeds up printing
2. reduces the chances of warping
3. saves resources
21
what are three ways to reduce the mass/ volume of a product/ prototype?
1. shell solid sections
2. consolidate parts
3. add ribbing to increase structural integrity
22
what is an engineering drawing?
a tool to communicate design and manufacturing intent
23
what are the three types of engineering drawing?
1. detail
2. assembly
3. layout
24
what is a detailed engineering drawing?
used to capture the detail of a design in a form that allows parts (components) or a product to be fully described, geometrically or functionally
25
what is an assembly engineering drawing?
use to capture the detail of a design relating to the number and type of parts in a product, and how they interact with each other to form subassemblies and the final product.
26
what is a layout engineering drawing?
depict pictorial, notational or dimensional data to convey the design solution used in preparing other engineering drawings.
27
what 5 ways do engineering drawings convey design intent?
1. presenting an accurate, to scale view of the proposed product to managers, clients, members of the design team.
2. accurately describe the size and form of a part for manufacture
3. accurately describe how parts are assembled
4. used to verify a produced part is the same as that specified
5. providing after sales information such as assembly instructions, maintenance details etc.
28
what are three fundamental principles of an engineering drawing?
1. an understanding of geometry and drawing conventions is key
2. engineering drawings are produced in 2 dimensional
3. the subject of engineering drawings are 3D
29
what is orthographic projection?
process of representing 3D objects in 2 dimensions
30
layout of first angle projection?
opposite way to how you think.
31
layout of third angle projection?
front in centre, right to the right, left to the left, etc.
32
what are two main types of thread?
1. internal
2. external
33
what are 4 common things in an engineering drawing?
1. repeated features
2. symmetry
3. partial representations (detailed views)
4. interrupted views - allow large parts to be shown by removing uniform sections of material.
34
what is hatching?
shading in a drawing
35
what is knurling?
typically used to provide a textile grip to a machined part. Either straight or crossed.
36
what are 4 rules about dimensioning layout?
1. clarity is the main aim
2. dimensions can go on any relevant view to avoid clutter
3. don't repeat dimensions
4. you cant dimension hidden features
37
what are two types of dimensioning layout?
1. chain dimensioning
2. parallel dimensioning
38
what is chain dimensioning?
chains of single dimensions are arranged in a row
39
what is parallel dimensioning?
dimension lines shall be drawn parallel in one, two or three orthogonal (at right angle) directions
40
what is Cartesian coordinate dimensioning?
coordinates are defined starting from the origin by linear dimensions. Has y and x-axis for the points.
41
what is advanced parallel dimensioning called?
running dimensioning
42
what is a section?
an elemental slice, having no substance, taken through an object or part of an object revealing the outline shape solely at the cutting plane
43
what is a sectional view?
the resultant view at a cutting plane, revealing all detail of an object or part of an object including other visible outlines beyond the cutting plane when seen in the direction of view. it is everything visible from the cutting plane onwards.
44
why are removed sections useful?
useful for conveying form along a length. Can be shown in any sensible location as they don't have to fit the projection conventions
45
what is the line type order of priority? (6)
1. visible outlines and edges
2. hidden outlines and edges
3. cutting planes
4. centre lines
5. outlines and edges of adjacent parts etc
6. projection lines
46
what is another name for an assembly drawing?
a general arrangement
47
what is the purpose of a general arrangement?
to convey how the product or sub-assembly is assembled
48
when dimensioning curved features, what are the two methods for doing this?
1. Radii - locate the centre from a suitable datum
2. coordinate dimensions - dimensioning of curved features and splines can be performed using linear coordinates
49
what are tolerances?
numerical limits of size, shape or a description of geometrical dimension.
50
why use dimensioning tolerancing?
1. to reflect that manufacturing processes are nither perfectly accurate or perfectly repeatable
2. to accept that we cannot eliminate variation, instead we need to work with it or manage it.
51
what does this tolerance mean: 12 +- 0.01
nominal size is 12mm but can vary between 0.1mm above or 0.1mm below.
52
what does this tolerance mean: 12 +0.01 - 0.00
nominal size is 12mm but can vary between 0.01 above but cannot be less than 12mm
53
what does this tolerance mean: 12.006 - 11.998
size can vary between the two specified limits
54