ENGS 171 Industrial Ecology Redesigning the Bicycle
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Alan Salas, Kevin Dahms, Jess Zarker, Jose Ordonez, Robbie Moss ENGS 171 Industrial Ecology Redesigning the Bicycle
description
ENGS 171 Industrial Ecology Redesigning the Bicycle. Alan Salas, Kevin Dahms , Jess Zarker , Jose Ordonez, Robbie Moss. Recap from last time. Part 2: Redesign. Design Requirements. Seat Mast Tube. FUNCTION: To support the weight of the person. Acts as a column in compression - PowerPoint PPT Presentation
Transcript of ENGS 171 Industrial Ecology Redesigning the Bicycle
Alan Salas, Kevin Dahms, Jess Zarker, Jose Ordonez, Robbie Moss
ENGS 171Industrial EcologyRedesigning the Bicycle
Recap from last time
Materials Manufacture Transport Use Disposal/End of Life0.00
5000.00
10000.00
15000.00
20000.00
25000.00
Water Use Audit
Phase
Wat
er U
se (k
g)
Frame Wheels Air Tube
Fork Handle Bar
Crank Rear Wheel Frame
Front Wheel Frame
02468
101214161820
Materials: Components with Highest Embodied CO2
% o
f Tot
al C
O2
Part 2: Redesign
Design Requirements
Seat Mast Tube
FUNCTION:To support the weight of the person. Acts as a column in compression
OBJECTIVES:Ideally, minimize environmental impact and mass
CONSTRAINTS:RecyclableHigh strength and stiffness
FREE VARIABLES:Material choice, shape, color
IndicesFor minimizing environmental impact (embodied energy and CO2)
Minimizing Embodied EnergyMinimize Hmρ/ E1/2 for stiffnessMinimize Hmρ/ σy for strength
Minimizing CO2
Minimize CO2ρ/ E1/2 for stiffnessMinimize CO2ρ/ σy for strength
Indices for other componentsPart Configuration Function(s) Constraint(s) Objective(s)
Fork1 Beam (loaded in
bending)2 Columns (in compression)
Provide support; link between handlebar
and front wheel
High stiffness, high strength
Minimize: mass, embodied energy, carbon emissions
Frame6 Beams (loaded in
bending)1 Column (in compression)
Provide structural support for bike
Handlebar1 Beam (loaded in
bending)1 Column (in compression)
Give direction, provide stability, support part of rider's weight,
platform for break handles
Seat Mast Tube
1 Column (in compression)
Support rider's weight
Indices for other components
Material Selection
Analysis for seat mast tube (modeled as a column)
Material Selection
Bamboo!
Low-alloy steelLower embodied energy!
Material Selection
Bamboo!
Low-alloy steel
Lower CO2
Material Selection
Bamboo!Lower density
Low-alloy steel
Trade-off Strategies
Mass vs. Cost
Bamboo, Softwood and Hardwood
Low-alloy steel
Cheaper
Mass vs. Embodied Energy
Bamboo, Softwood and Hardwood
Low-alloy steel
Less embodied energy
Cost vs. CO2
Bamboo, Softwood and Hardwood
Low-alloy steel
Less CO2
Cost vs. Embodied Energy
Bamboo, Softwood and Hardwood
Low-alloy steel
Less embodied energy
Shape
29 mm
38 mm
4.5 mm
Shape
- These specifications are for Iron bamboo, which is the strongest type
- If it is a more flexible bamboo, use wider and thicker tubing
- If internal diameter is less than 29 mm, there will be a hoop stress, which we didn’t look into carefully in this analysis.
http://www.useful-arts.com/sua/instructions/bamboobikekit/harvest/
Use Phase Analysis• Negligible environmental impact• NEXT Bike• Maintenance: paint, wheels, lost accessories, oil• Once child grows, bike becomes obsolete
Use Phase Analysis (cont.)• BamBIKE:• Introduce a service program• Convert the product into a service• Incentive: offer free repairs (only cost is
purchasing the parts), offer discounts, etc.• Return old bike, obtain new larger bike at a
discount
“If your child grows faster than bamboo, we have a solution for you!”
Discussion of Redesign
Frame
Joints + bamboo
Fork
Handle bar
Seat tube
Eco-Audit of redesigned bike
_x0008_M
ateria
l
_x000b_M
anufac
ture
Transport
_x0004_U
se
_x0008_D
isposal
_x0015_En
d of Life potential
-300
-200
-100
0
100
200
300
400
500
Original
New Design
2nd Life (Remanufactured)
Ener
gy (M
J)
34% reduction
_x0008_M
ateria
l
_x000b_M
anufac
ture
Transport
_x0004_U
se
_x0008_D
isposal
_x0015_En
d of Life potential
-15
-10
-5
0
5
10
15
20
25
Original
New Design
2nd Life (Remanufactured)
CO2
(kg)
CO2 of Entire process
40% reduction
Specifically looking at components
_x0005_FrameHandlebars
_x0004_Fork Seat Tube0
10
20
30
40
50
60
70
Original
New Design
Ener
gy (
MJ )
75% reduction
87%
CO2 of materials
_x0005_FrameHandlebars
_x0004_Fork Seat Tube0
0.5
1
1.5
2
2.5
3
3.5
4
4.5
Original
New Design
CO2
( kg
)
74% reduction
87%
Water-audit of redesigned bike
Materials Manufacture Transport Use End of Life0
5000
10000
15000
20000
25000
Water Audit: Existing vs. Redesign
OriginalRedesign
kg o
f Wat
er
Why isn’t there a significant change???
Economic Analysis• Materials:• Low alloy steel
• 0.89-0.93 USD/kg• At 3.68 kg, price is $3.35
• Bamboo• 1.37-2.05 USD/kg
• At 0.4 kg, price is $0.82
• BUT, labor is a problem:• More labor intensive to assemble BamBIKE, so higher costs are
associated• This is why it is currently only offered to very specialized, high end
consumers
Economic Analysis• CNN article published today about a bamboo bike company
located in Zambia:
http://edition.cnn.com/2012/05/31/business/bamboo-bicycles-zambia-zambikes/index.html?hpt=hp_c4
“Each frame takes between 40 and 60 man hours to make […] Every piece of bamboo is having different colors, different bend, so every frame is unique."
• That explains the high costs, and why these “high-end, lightweight bicycles” have “a price tag of around $900” and are “primarily aimed at the international market”.
Considering Aesthetics: Paint and Plastics
Aesthetics are a major feature refractive quality of paint, extra features (painted plastic), logo designs
Aesthetics are also subjective; malleable• Don’t outweigh the environmental impacts:
• Greenhouse gas emissions: VOCs, CO2, NOx, SOx , and PM
• Health Concerns for workers• “Eco-Design”
Water-based paintWater-based non-toxic wood varnish
logo
Conclusions and Recommendations
Findings• Bamboo is an appropriate substitute for steel
Considerations• Industrial infrastructure is currently nonexistent• This is the foundation for a sustainable lifestyle
• Saving 91 MJ per bike means saving energy of
245 bananas per unit!!!
There are other important benefits of bamboo that could be further exploited:
“One of nature's fastest growing resources”
“Has great shock absorbing abilities that contribute to a smooth and eco-friendly ride”
http://edition.cnn.com/2012/05/31/business/bamboo-bicycles-zambia-zambikes/index.html?hpt=hp_c4
Conclusions and Recommendations
Moving forward… Hemp
Wood
Wood
and ideally…DIAMOND!
Questions?
