Nuclear winter: Implications for civil defense, Final report
Final Report Defense 021509
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Transcript of Final Report Defense 021509
Design for Manufacturability and Assembly of the
endogo® Palmable Endoscopic Camera
Matthew R. Ostrander
February 17th, 2009
2
Overview
Background
Goal
Problem Definition
Approach
Results
Q&A
3
Background
Current archiving accomplished with large, expensive equipment
endogo® combines portability/simplicity with need for endoscopic imagery
Provides a platform that combines available imaging technology with the endoscope
Result: Compact, digital endoscopic imaging device, ergonomically designed to provide maximal comfort for short and prolonged use
4
Goal
Recommend design and assembly
process changes that will enable
production of the endogo® at reduced
cost, increased speed and higher quality
5
Problem Definition
Design effort focused on functionality –This project focuses on manufacturability
Metrics guide the project
Cycle Time
Metrics and Order-Winning Criteria (OWC) assist in identification of figures of merit
Weighting matrix resulted in metricsselected for this project
6
Approach
Model/Analyze Baseline Design
Extend® Model
Part-count reduction
DFA Index Estimation
Insertion Time Estimation
Acquisition Time Estimation
Defect Estimation and Defect Table
Cycle Time, Distance, Quality, Inventory
Estimation
7
Approach (continued)
Model/Analyze New Design
Extend® Model
Material Selection (Dimensionless Ranking)
DFA Index Estimation
Defect Estimation
Cycle Time, Distance, Quality, Inventory
Estimation
8
Approach
Flowchart
Tasks
Interdependent
- DFA Index
- Inventory Turns
- Quality
- Distance
- Cycle Time
Baseline Design
Extend
Model
Part-Count
Reduction
Assembly /
Acquisition
Time
Estimation
Probability
of Defect
Calculation
Metrics
“Filter”
Process
Redesgin
Material
Selection
(Dimensionless
Ranking)
New Process
(Assembly)
New Product
(Manufacture)
New Design
- DFA Index
- Inventory Turns
- Quality
- Distance
- Cycle Time
Compare
Baseline Extend
Model
10
Extend Model (1 of 2)
Benefits of Starting with the Model
Clear understanding of the process
Provides Inventory Turns estimate
Inventory Turns calculated for the baseline
and new designs
$,
$,
InventoryAverageDaily
AnnuallySoldGoodsofCostTurnsInventory
11
Extend Model (2 of 2)
Average daily inventory taken from the
model by determining stock and work in
process
Cost of goods sold in a year taken from
the total number of cameras produced in a
single model run (simulates one year)
12
Baseline Extend Model (1 of 5)
13
Baseline Extend Model (2 of 5)
Order Size (Cameras per Order) is
calculated by dividing subassembly lead
time (Minutes per Order) by the endogo
lead time (Minutes per Camera)
TimeLeadendogo
TimeLeadySubassemblSizeOrder
14
Baseline Extend Model (3 of 5)
15
Baseline Extend Model (4 of 5)
16
Baseline Extend Model (5 of 5)
Cycle Time variation due to production approach
10 built in rapid succession followed by long period
until next 10
With 1 piece flow, Cycle Time between 285 and 276
minutes at the 99% confidence level
Average Cycle Time representative of system’s true
capability because demand exceeds capacity
Inventory Turns calculated across 30 model runs
Metric Average Upper Bound (99% Confidence)
Lower Bound (99% Confidence)
Inventory Turns 10.9 11.0 10.8 Cycle Time, min 278 387 169
DFMA
Considerations
18
DFMA Considerations (1 of 12)
Part Count Reduction
During operation of the product, does the part move relative to all other parts already assembled?
Must the part be of a different material than or be isolated from all other parts already assembled?
Must the part be separate from all other parts already assembled because otherwise necessary assembly of other separate parts would be impossible?
19
DFMA Considerations (2 of 12)
Part count reduced from 92 to 42
Example: Display Mounting Ring and LCD Ring Neck
Injection Mold the neck and ring in once piece
The result, 42, is Nmin in the DFA Index (next)
20
DFMA Considerations (3 of 12)
DFA Index Calculation
assemblycompletetotimeestimatedt
partonefortimeassemblybasict
partsofnumberltheoreticalowestN
IndexDFAE
where
ttNE
ma
a
ma
maama
min
min
,
/
21
DFMA Considerations (4 of 12)
ta calculation
Boothroyd assumes 3 seconds
Assumes no knowledge of actual process
Attempt to find a basic assembly time tailored
to this particular design
22
DFMA Considerations (5 of 12)
ta calculation
First Attempt: DFA Index Greater than One
timecycletheofdevst
designbaselineinpartsofnumberactualN
cameraonebuildtorequiredtimeCT
where
N
CTt
CT
actual
actual
CTa
..
,
282.1
23
DFMA Considerations (6 of 12)
ta calculation
Second Attempt: Data not Normal
steppertimeassemblyestimatedtheofdevst
steppertimeassemblyestimatedaveraget
where
tt
estimated
averageestimated
estimatedaverageestimateda
..
,
282.1
,
,
24
DFMA Considerations (7 of 12)
ta calculation
Second Attempt: Data not Normal
Assembly Times, seconds
Pe
rce
nt
2520151050-5
99
95
90
80
70
60
50
40
30
20
10
5
1
Mean
<0.005
7.355
StDev 5.435
N 30
AD 1.967
P-Value
Normality Test of the Assembly Times
Normal
25
DFMA Considerations (8 of 12)
ta calculation
Third Attempt: Log-normal Successful
Log of Assembly Times
Pe
rce
nt
1.61.41.21.00.80.60.40.20.0
99
95
90
80
70
60
50
40
30
20
10
5
1 0.4
11
10
Mean
0.542
0.7733
StDev 0.2824
N 30
AD 0.307
P-Value
Normality Test of the Log of Assembly Times
Normal
26
DFMA Considerations (9 of 12)
ta calculation
Third Attempt: Log-normal Successful
Log of Assembly Times
Pe
rce
nt
1.61.41.21.00.80.60.40.20.0
99
95
90
80
70
60
50
40
30
20
10
5
1 0.4
11
10
Mean
0.542
0.7733
StDev 0.2824
N 30
AD 0.307
P-Value
Normality Test of the Log of Assembly Times
Normal
58.2411.0
411.0log
10
10
x
x
27
DFMA Considerations (10 of 12)
EASY TO
ALIGN
NOT EASY
TO ALIGN
EASY TO
ALIGN
NOT EASY
TO ALIGN
EASY TO
ALIGN
NOT EASY
TO ALIGN
0 1 2 3 4 5
NO ACCESS OR
VISION
DIFFICULTIES
0 1.5 3 2.6 5.2 1.8 3.3
OBSTRUCTED
ACCESS OR
RESTRICED VISION
1 3.7 5.2 4.8 7.4 4 5.5
OBSTRUCTED
ACCESS AND
RESTRICTED VISION
2 5.9 7.4 7 9.6 7.7 7.7
COPYRIGHT 1999 BOOTHROYD DEWHURST, INC.
SECURED BY SEPARATE OPERATION OR PART
NO HOLDING DOWN HOLDING DOWN
SECURED ON INSERTION
BY SNAP FIT
tma Calculation: Insertion Time Estimate
28
DFMA Considerations (11 of 12)
< 2mm < 2mm
SIZE > 15mm 6mm < SIZE < 15mm SIZE > 6mm SIZE > 15mm 6mm < SIZE < 15mm SIZE > 6mm
0 1 2 3 4 5
SYM < 360 0 1.13 1.43 1.69 1.84 2.17 2.45
360 ≤ SYM < 540 1 1.5 1.8 2.06 2.25 2.57 3
540 ≤ SYM < 720 2 1.8 2.1 2.36 2.57 2.9 3.18
SYM = 720 3 1.95 2.25 2.51 2.73 3.06 3.34
FOR PARTS THAT CAN BE GRASPED AND MANIPULATED WITH ONE HAND WITHOUT THE AID OF GRASPING TOOLS
COPYRIGHT 1999 BOOTHROYD DEWHURST, INC.
NO HANDLING DIFFICULTIES PART NESTS OR TANGLES
THICKNESS > 2mm THICKNESS > 2mm
tma Calculation: Acquisition Time Estimate
29
DFMA Considerations (12 of 12)
tma calculation: Sum all estimates
ta, s tma, s Nmin Ema Baseline Design 2.58 2273 33 0.04
Distance
Calculations
31
Clean Room
Flow Hoods
Ramp and Loading Dock
Warehouse
48' 8 x 45
Clean Room (Future)
General Manufacturing 70 X 50
20 X 18
Sink
40 x 45
ShopBiohazard LabHall
Lech
Scott Rosanna Mark
Endogo Work Station
Receiving
Receiving
Rack
Endogo Rack
Distance Calculations (1 of )
1 – Entry
2 – Receiving Rack
3 – Receiving
4 – Receiving Rack
5 – Inspection
6 – Receiving Rack
7 – Storage
8 – Machining
9 – Assembly
10 – Ship
25,500 feet
32
Clean Room
Flow Hoods
Ramp and Loading Dock
Warehouse
48' 8 x 45
Clean Room (Future)
General Manufacturing 70 X 50
20 X 18
Sink
40 x 45
ShopBiohazard LabHall
Lech
Scott Rosanna Mark
Endogo Work Station
Receiving
Receiving Rack
Endogo Rack
Distance Calculations (1 of )
1 – Entry
2 – Receiving/Inspection
3 – Receiving Rack
4 – endogo® Worksation
4,840 feet
Assembly
Modifications
34
Workstation Changes
Contain all parts on the workbench rather
than in the storage rack
Do not “kit” each camera in the same bin
Organize each part bin in order of
assembly
Mark bins with part number and picture bin
35
Pareto Chart
0
20
40
60
80
100
120
140
160
Process Steps
Acti
vit
y T
ime,
seco
nd
s
0%
10%
20%
30%
40%
50%
60%
70%
80%
90%
100%
Cu
mu
lati
ve %
Baseline New Design Average After Re-design
Cumulative %, New Design Cumulative %, Baseline
36
DFA Index Values ta, s tma, s Nmin Ema
Baseline Design 2.58 2273 33 0.04 New Design 2.58 221 33 0.4
tma estimated primarily by way of
Boothroyd techniques
10-fold decrease in tma led to 10-fold
increase in DFA Index
The ideal would take 85 seconds to
assemble
Quality Estimates
38
Quality Estimates
assemblyperoperationsofnumbern
soperationpertimeassemblyestimatedDFAaveraget
assemblyperdefectofyprobabilitD
where
tforD
tfortD
i
a
ia
i
n
ia
,
,
3,0
3,30001.011
n ti, seconds Da, ppm
Baseline Design 76 30 190,000 New Design 29 7.0 12,000
Material and
Process Selection
40
Material and Process Selection
Dimensionless Ranking
rd parametethe derived to form hat is useExponent tm
determined is being he N-valueor which tmaterial ftheofpropertynP
sg materialengineerinof common rangeaforparameterderivedLowestD
sg materialengineerinof common rangeaforparameterderivedHighestD
parameterDerivedD
PPPD
where
DDDDN
n
thn
m
n
mm n
min
max
21
minmax10min10
21
,
)/(log/)/(log100
Derived Parameter Description Exponents m1 m2 m3 m4 m5 Best YT at Minimized Weight and $ -1 1 0 0 -2 Best YC and Minimized Weight and $ -1 0 0 1 -2 Best Beam/Plate Strength at Minimized Weight and $ -1 1/2 0 0 -2 Best Stiffness at Minimized Weight and $ -1 0 1/3 0 -2
41
Initial broad group of
candidate materials
Cost Tensile Yield Strength Elastic
Modulus Compressive
Yield Strength Density
$/kg MN/m2 MN/m2 MN/m2 kg/m3
Gray Cast Iron 3.32E-01 2.93E+02 1.34E+05 2.93E+02 7.21E+03
Ductile Iron 4.08E-01 4.48E+02 1.65E+05 3.10E+02 7.13E+03
Malleable Iron 4.85E-01 3.45E+02 1.60E+05 3.45E+02 7.38E+03
Mild Steel 1.15E+00 2.62E+02 2.07E+05 2.62E+02 7.77E+03
Alloy Steel 7.14E+00 1.38E+03 2.07E+05 1.38E+03 7.85E+03
Stainless Steel 3.19E+00 2.48E+02 1.93E+05 2.48E+02 8.04E+03
Al (High Strength) 6.12E+00 1.93E+02 7.10E+04 1.93E+02 2.75E+03
Beryllium Copper 4.46E+01 1.10E+03 1.28E+05 1.10E+03 8.27E+03
Copper, Hard 3.32E+00 3.10E+02 1.17E+05 3.10E+02 8.96E+03
Magnesium 8.93E+00 2.34E+02 4.48E+04 2.34E+02 1.80E+03
Titanium 3.11E+01 9.45E+02 1.13E+05 9.45E+02 4.74E+03
Lead 3.32E+00 2.00E+01 1.52E+04 2.00E+01 1.14E+04
Epoxy 6.12E+00 6.55E+01 3.10E+03 2.48E+02 1.91E+03
HDPE 1.39E+00 2.48E+01 8.27E+02 2.48E+01 9.71E+02
Polycarbonate (Glass-
reinforced) 2.45E+00 1.59E+02 1.16E+04 1.45E+02 1.53E+03
Rubber 4.03E+00 2.76E+01 4.59E+00 2.76E+01 9.71E+02
Polyurethane Foam 2.04E+00 1.52E+01 1.08E+02 1.72E+01 4.99E+02
Particle Board 4.08E-01 1.55E+01 2.93E+03 1.45E+01 6.10E+02
Pine 2.38E+00 7.93E+01 8.27E+03 3.31E+01 3.61E+02
Diamond 8.42E+02 2.69E+02 1.03E+06 4.00E+03 3.52E+03
Silicon Carbide (Sintered) 7.65E+01 6.90E+01 3.31E+05 1.03E+03 2.97E+03
Tungsten Carbide 3.06E+02 8.96E+02 5.39E+05 4.95E+03 1.33E+04
Glass 3.83E-01 9.17E+01 7.31E+04 1.38E+03 2.47E+03
Pottery 7.65E-01 3.31E+01 7.03E+04 5.00E+02 2.22E+03
Concrete 1.53E-01 1.65E+00 3.00E+04 2.48E+01 2.50E+03
Cork 1.74E+00 1.00E+00 2.00E+01 1.00E+00 1.39E+02
Al-Li (2090) 1.66E+02 4.55E+02 6.90E+04 4.55E+02 2.55E+03
42
Stiffest at minimum
weight and cost
Strongest in Tension
at minimum weight
and cost
Stiffest Material at Minimum Weight and Cost
Strongest Tension Member at Minimum Weight and Cost
Particle Board 100 Pine 100
Cork 99 Particle Board 90
Pine 97 Glass 81
Concrete 90 Polyurethane Foam 78
Glass 85 Cork 78
Pottery 81 Polycarbonate (Glass-
reinforced) 77
Polyurethane Foam 79 Ductile Iron 74
Polyethylene (high-density) 77 Polyethylene (high-density) 73
Polycarbonate (Glass-reinforced) 71 Gray Cast Iron 72
Gray Cast Iron 69 Malleable Iron 69
Ductile Iron 68 Pottery 65
Malleable Iron 65 Magnesium 64
Magnesium 61 Rubber 63
Al (High Strength) 58 Al (High Strength) 57
Mild Steel 57 Mild Steel 56
Epoxy 55 Alloy Steel 54
Rubber 51 Epoxy 54
Stainless Steel 47 Concrete 48
Copper, Hard 44 Titanium 46
Alloy Steel 41 Stainless Steel 44
Silicon Carbide (Sintered) 38 Copper, Hard 44
Titanium 35 Aluminum-Lithium Alloys
(2090) 34
Lead 33 Beryllium Copper 32
Aluminum-Lithium Alloys (2090) 29 Silicon Carbide (Sintered) 19
Beryllium Copper 22 Lead 11
Diamond 17 Diamond 5
Tungsten Carbide 0 Tungsten Carbide 0
43
Strongest in
compression at
minimum weight and
cost
Strongest beam at
minimum weight and
cost
Strongest Compression Member at Minimum Weight and Cost
Strongest Beam or Plate at Minimum Cost and Weight
Glass 100 Cork 100
Pottery 84 Pine 100
Pine 82 Particle Board 99
Particle Board 81 Polyurethane Foam 88
Polyurethane Foam 70 Glass 82
Cork 68 Polyethylene (high-density) 81
Concrete 67 Polycarbonate (Glass-
reinforced) 76
Polycarbonate (Glass-reinforced) 67 Pottery 73
Polyethylene (high-density) 64 Rubber 72
Gray Cast Iron 62 Concrete 72
Ductile Iron 61 Ductile Iron 69
Malleable Iron 60 Gray Cast Iron 69
Epoxy 58 Malleable Iron 66
Magnesium 55 Magnesium 63
Rubber 53 Epoxy 60
Al (High Strength) 48 Al (High Strength) 58
Mild Steel 47 Mild Steel 56
Alloy Steel 45 Alloy Steel 46
Silicon Carbide (Sintered) 37 Stainless Steel 45
Titanium 36 Copper, Hard 44
Stainless Steel 34 Titanium 40
Copper, Hard 34 Aluminum-Lithium Alloys
(2090) 33
Aluminum-Lithium Alloys (2090) 23 Silicon Carbide (Sintered) 28
Diamond 22 Beryllium Copper 27
Beryllium Copper 22 Lead 27
Tungsten Carbide 7 Diamond 10
Lead 0 Tungsten Carbide 0
44
Full list of candidate
polymers Cost Tensile Yield
Strength Elastic
modulus Density Autoclave?
$/kg MN/m2 MN/m2 kg/m3
Polyethylene (high-density) 1.39 24.8 1080 971 No
Polycarbonate (30% Glass-reinforced) 2.45 118 11600 1433 Yes
Elastomer - Nitrile
Elastomer - SBR
Elastomer - Thermoplastic
For design simplification, elastomers will not be used. Buttons will be of the same material as the case.
Epoxy Epoxy was lower rated than HDPE in initial screening. Typically used in
composites. This is also a thermoset.
Nylon 6,6 1.79 69 2515 1140 No
Phenolic Brittle thermoset
Polycarbonate (PC) 2.45 63.8 7580 1200 Yes
Polyester (thermoset) Thermoset
PEEK Not injection moldable and is very expensive
LDPE 1.79 11.75 225 924.5 No
UHMWPE 2.49 24.5 690 940 ?
PET 2.82 59.3 3450 1345 ?
PMMA Transparent
Polypropylene(PP) 1.81 32.6 1345 931 Yes
PS Relatively brittle and transparent
PTFE Poor cold flow properties
PVC 1.98 42.75 3250 1440 No
Silicone, flexible cast Not injection moldable
Heat Resistant ABS 2.19 43.5 2200 990 Yes
Acrylic Transparent
Acetal 3.09 66 3800 1465 No
45
Final list of candidate
polymers
Compared relative to one
another
Some compared but not
listed:
High Density Polyethylene
Nylon 6,6
Low Density Polyethylene
Polyvinyl Chloride
Acetal
Tension
Beam or Plate
Strength Stiffest Beam Average
Polycarbonate (30% Glass-reinforced)
73 29 65 56
Polycarbonate (PC)
64 39 76 60
Ultra-high Molecular Weight
Polyethylene (UHMWPE)
62 69 81 71
Polyethylene Terephthalate
(PET) 65 43 70 59
Polypropylene (PP)
100 100 100 100
Heat Resistant Acrylonitrile
butadiene styrene (ABS)
98 89 95 94
New Design Extend
Model
47
New Design Extend Model
Fundamental structure remains the same
Reduction of the number of steps due to
part count reduction
Elimination of “pre-work”
Reduction of re-work
48
Baseline Extend Model Results
0 5000 10000 15000 20000 25000 30000 35000 40000 45000 50000 55000 60000
0
3.05
6.1
9.15
12.2
15.25
18.3
21.35
24.4
27.45
30.5
33.55
36.6
39.65
42.7
45.75
48.8
51.85
54.9
57.95
61
TIME, MINUTES
CAMERASModel Output, Baseline
TOTAL STOCK WIP True INVENTORY
49
New Extend Model Results
0 5000 10000 15000 20000 25000 30000 35000 40000 45000 50000 55000 60000
0
0.95
1.9
2.85
3.8
4.75
5.7
6.65
7.6
8.55
9.5
10.45
11.4
12.35
13.3
14.25
15.2
16.15
17.1
18.05
19
TIME, MINUTES
NUMBER OF CAMERASModel Output, New Design
TOTAL STOCK TOTAL WIP INSTANTANEOUS I… INVENTORY AVERA…
50
Results Summary Metric Average
Inventory Turns 16.4 Baseline Design
Cycle Time, min 267
Inventory Turns 107 New Design
Cycle Time, min 111
Inventory Turns 30 Target
Cycle Time, min ≤ 120
n ti, seconds Da, ppm
Baseline Design 76 30 190,000
New Design 30 7.0 12,000
Target - - ≤ 44,000
Distance, feet
Baseline Design 25,500
New Design 4,840
Target ≤ 5,000
51
52
53
Deliverables
Product design changes
Process design changes
Material selection changes
Inventory Turns estimation for baseline and new design
Quality estimation for baseline and new design
Distance estimation for baseline and new design
Cycle Time estimation for baseline and new design
Extend® - based model of manufacturing processes for baseline and new design
Final report
Final defense briefing
54
Weighting Matrix
Metrics
OWC Set-Up Time Quality
Space Ratio Inventory Flexibility Distance Uptime Weight
Price 1
Quality 10
Lead Time 1
Delivery Reliability 2
Flexibility 0
Innovation 0
Size 0
Design Leadership 0
BACK
55
OWC
BACK
Order-Winning Criterion Definition
Price The cost to the consumer of the product under consideration.
Quality The perceived quality by the consumer of the product under consideration.
Lead Time The duration of time from the moment the consumer orders the product under consideration to the moment of consumer receipt.
Delivery Reliability The repeatability of lead time.
Flexibility The number of parts that can be produced on the same machine.
Innovation Ability An organization’s capacity for producing new marketable products.
Size The volume of the product under consideration.
Design Leadership An organization’s capacity for transforming concepts into finished products.
56
Metrics Identified for Project
BACK
Metric Weighted Score
Redesign Target
Inventory 14 30 turns
Quality 11
Captured and
Warranty: ≤ 44000 ppm
Distance 11 ≤ 5000 feet
Cycle Time – ≤ 120
minutes
57
Metrics
BACK
58
Metric Units Definition
Inventory Inventory Turns
Inventory Turns for a product is equal to the cost of goods sold divided by the average inventory value
Flexibility number of parts
The number different parts that can be produced on the same machine.
Distance feet The measure of the total linear feet of a part’s travel through the plant from raw material in receiving to finished products in shipping. This includes the sum of the individual routes of each subassembly. For example, if a plant manufactures a paper cup, the side of the cup travels 10 feet to get to the location where it is mated to the bottom. The bottom at that point has also traveled 10 feet. After the two are mated, it travels another 10 feet to be given a finish and then to shipping. The total Distance is then 30 feet.
Uptime percent The percentage of time a machine is producing to specifications compared to the total time that production can be scheduled.
Metrics (continued)
BACK
59
Inventory Turns
$,
$,
InventoryAverageDaily
AnnuallySoldGoodsofCostTurnsInventory
BACK
60
Dimensionless Ranking
rd parametethe derived to form hat is useExponent tm
valuethe lowestat it has except thSame as PP
ialsring materon engineege of comm for a ranhest valueas the higial that hof a mater property nP
determined is being he N-valueor which tmaterial ftheofpropertynP
propertiesvaluedlowesttheofallofncombinatiothewithparameterDerivedD
propertiesvaluedhighesttheofallofncombinatiothewithparameterDerivedD
parameterDerivedD
PPPD
PPPD
PPPD
where
DDDDN
n
n,n
thn
thn
m
n
mm
m
n
mm
m
n
mm
n
n
n
maxmin,
max,
min
max
min,min,2min,1min
max,max,2max,1max
21
minmax10min10
21
21
21
,
)/(log/)/(log100
BACK
61
Dimensionless Ranking Example
Five parameters form derived
parameters
1. Cost, $/kg
2. Tensile Yield Strength, MN/m2
3. Elastic Modulus, MN/m2
4. Compressive Yield Strength, MN/m2
5. Density, kg/m3
BACK
62
Most likely derived parameter will be “best
tensile yield strength at minimized cost”
Using previous numbering convention and
dimensionless parameter equation: m2 = 1,
m1 = m5 = -1, and m3 = m4 = 0
This produces the derived parameter:
Yt /r Cm
Dimensionless Ranking Example
BACK
63
Dimensionless Ranking Example
BACK
m1 m2 m3 m4 m5
-1 1 0 0 -1
Cost
Tensile
yield str.
Elastic
modulus
Compressive
yield str. Density
Derived
parameter N
$/kg MN/m2
MN/m2
MN/m2
kg/m3
Pmax 7.26E+02 1.38E+03 1.03E+06 4.95E+03 1.33E+04 1.43E-04 100
Pmin 1.32E-01 1.00E+00 4.95E+00 1.00E+00 1.39E+02 5.45E-02 0
Polyethylene
(high-density) 7.48E-01 2.48E+01 8.27E+02 2.48E+01 9.71E+02 3.41E-02 8
Titanium 2.68E+01 9.45E+02 1.13E+05 9.45E+02 4.74E+03 7.44E-03 34
64
Part-count Reduction
During operation of the product, does the part move relative to all other parts already assembled?
Must the part be of a different material than or be isolated from all other parts already assembled?
Must the part be separate from all other parts already assembled because otherwise necessary assembly of other separate parts would be impossible?
BACK
65
DFA Index
assemblycompletetotimeestimatedt
partonefortimeassemblybasict
partsofnumberltheoreticalowestN
IndexDFAE
where
ttNE
ma
a
ma
maama
min
min
,
/
BACK
66
Basic Assembly Time
timecycletheofdevst
designbaselineinpartsofnumberactualN
camerapertimecycleCT
where
N
CTt
CT
actual
actual
CTa
..
,
282.1
BACK
67
Probability of Defect (Entire
Assembly)
assemblyperoperationsofnumbern
soperationpertimeassemblyestimatedDFAaveraget
assemblyperdefectofyprobabilitD
where
tforD
tfortD
i
a
ia
i
n
ia
,
,
3,0
3,30001.011
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