Cost-minimized design for Hyperloop network with ...
Transcript of Cost-minimized design for Hyperloop network with ...
Cost-minimized design for Hyperloop networkwith heuristically optimized
location and numberof the stations
1Hansol Yoo, 1Ikki Kim , 2B. Brian Park, 3Jong-hak Kim1 Hanyang University at Ansan, South Korea
2 University of Virginia at Charlottesville, VA., U.S.A.
3 Korea Research Institute for Human Settlements (KHRIS), South Korea
5th Annual Summer Conference on Livable Communities (ACLC)
Hosted by the Transportation Research Center for Livable Communities (TRCLC)
June 21 - 22, 2018 at Western Michigan University, Kalamazoo, Michigan
1
1 Research motivationNew technology / Needs of Infrastructure
2Characteristics of Hyperloop and other transportation modes
Speed / Vehicle capacity / Line capacity / Acceleration and deceleration
3 Type of transit network systemOne-to-one / Many-to-many system
4 The process of heuristic optimized network designMinimum spanning tree problem / Heuristic network design process
7 Mode choice analysis and share of HyperloopMultinomial Logit model / Mode shift analysis
5 Minimum spanning tree analysis with various number of citiesFinding a set of major corridors with given travel demand
6 Heuristic refinement and simplification of the networkCombining the MSP results of all corridors / Refinement and Simplification
Hanyang University2
Hanyang University
Research motivation
• Hyperloop technology has become more and more actualized and
applicable into real world since Elon Musk suggested in 2012.
• Many scientists have concentrated their researches mostly on
vehicle technologies and mechanical structure of the vacuum
tube itself based on the assumption of completion of a network.
• However, a network plan for effective and convenient usage
should be preceded. The network plan will be followed by the
infrastructure plan and its construction including land acquisition
which is expected to take about 10 to 20 years.
• That is why the research on the Hyperloop network design is
needed in advance before the Hyperloop technology completion.
3
Hanyang University
ModeSpeed
Km/h (Mile/h)
VehicleCapacitypersons
Headwaysecond
LineCapacity
Accel/decel distanceKm (Mile)
Walk 12.7 - 4.1
(1.7 - 2.6)1 2.6 900 - 1,380prs/h/ft 2 -
Bicycle 1 20.6 (12.8) 1 2.3 1,600prs/h/lane -
Car 1110 - 120 3
(68 - 75)1 - 5 1.5 3 2,400 - 12,000prs/h/lane 3
0.14 - 0.19(0.09 - 0.12)4
Bus 5 90 (56) 80 - 125 75 - 96 3,000 - 6,000prs/h 0.22 (0.14)
Rail 580 - 130(50 - 81)
800 - 1,750 120 - 360 8,000 - 45,000prs/h 0.51 (0.32)
High speed rail (HSR)
300 - 320(186 - 199)
508 - 935 6 150 - 180 7 10,160 - 22,440prs/hAccel: 15.2 (9.4)
Decel: 6.4 (4) 6
Airplane 8829 - 903
(515 - 561)132 - 544 61 - 72 9 7,790 - 27,200prs/h
3 (1.9)(take off distance)
Hyperloop 1,220 (758) 28 10 30 - 120 11 840 - 3,360prs/h 12 (7.5)
1 HCM20102 LOS E, pedestrians per minute per foot of walkway width,3 Freeway, LOS E4 hypertextbook.com/facts/2001/MeredithBarricella.shtml5 Vuchic, V. R. (2007)6 Suh, Sunduck D. et al. (2005), en.wikipedia.org/wiki/TGV
7 Emery, D. (2011)8 Airbus318, Airbus380, en.wikipedia.org9 Hourly capacity of runway, Horonjeff, R., et al. (2010)10 Musk, E. (2013). 11 Taylor, C. L ., et al. (2016)
Characteristics of Hyperloop and others
4
Hanyang University
• Super-high speed as a ground transport mode
▷ Broader regions can be served with high accessibility to a CBD.
▷ Safety issues need to be seriously considered (The line radius should be
sufficiently large).
• Fully automated operation
▷ smaller-capacity vehicles can be adoptable safely even in high speed.
▷ Very frequent dispatch (short headway) can be possible.
• Relatively small capacity of a vehicle
▷ It can serve OD pairs having relatively small travel demand where the
service was not available by a mass transit mode such as train or airplane.
• Exclusive right-of-way from other type of vehicles
▷ There in no vehicle congestion by interruption of other type of vehicles
Characteristics of Hyperloop service
and network design
5
Hanyang University
• Requirement of relatively shorter distance to reach the maximum speed
▷ It can keep higher operating speed because it reach quickly to the maximum
speed after departure.
▷ Safe operation is possible in case of an unexpected accident due to
relatively short stopping distance.
• Relatively small passenger’s space of the vehicle inside for stretching and
walking
▷ It is very difficult to travel between OD pairs that are very distant from each
other without any intermediate rest places.
▷ The maximum travel time, that a traveler tolerates, might be two to three
hours (about 2,400 – 3,600 Km (1,500 – 2,250 miles) by Hyperloop)
Characteristics of Hyperloop service
and network design
6
Hanyang University
Hyperloop station concept and network design
These graphics came from : https://www.archdaily.com/799341/rb-systems-proposes-cutting-edge-hyperloop-station
7
Hanyang University
Travel time by a Hyperloop in the United States
Los Angels – Chicago (1 hr. 44 min.)2,085 Km (1743 miles), 104 minutes
New York – Los Angels ( 3 hr. 15 min.)3,940 Km (2,448 miles), 195 minutes
Los Angels – San FranciscoElon Musk estimated 35 minutes560 Km (348 miles), 29 minutes
New York – Chicago1,147 Km (713 miles), 58 minutes
※ The travel times were ideally calculated with the maximum speed of 2,200 Kim/h (763 miles/h)
while considering the acceleration and deceleration at both ends of OD.
Musk, E., "Hyperloop alpha.“, SpaceX. August 13, 2013
8
Hanyang University
Basic concept of transit network design :
One-to-one system
A
B
C
D
E
H
I
J
K
L
Origin city Destination city
9
Hanyang University
Basic concept of transit network design :
Many-to-many (hub-and-spoke) system
A
B
C
D
E
H
I
J
K
L
NM
Collecting process Line-haul process Distributing process
SMALL
CITIES
SMALL
CITIES
Departure Hub Arrival Hub
LARGE CITY LARGE CITY
Modes : Walk, bicycle, car, bus Modes : regional bus, rail, HSR, airplane Modes : Walk, bicycle, car, bus
10
Hanyang University
Accessibility and speed :
Number of stops/stations within a line
M B C EN
Express line
Normal line
LARGE CITY
SMALL CITY SMALL CITY SMALL CITY
LARGE CITY
Express line : Less accessibility, higher speed, less travel time
Normal line : higher accessibility, Lower speed, more travel time
11
Hanyang University
Proposed one-to-one network
by separating access branch from by-pass tube
By-pass
By-pass
CityStation
CityStation
Access branch
Access branch
Fully automated operation makes it possible to have a small capacity vehicle. As a
result, direct service of a Hyperloop without intermediate stops and transfer is
possible for each OD pair having relatively small demand if the station of each city
has a egress and ingress access branch separately from the main by-pass tube.
12
Hanyang University
Proposed Hyperloop network system :
Satisfaction in both of accessibility and speed
M B C EN
LARGE CITY SMALL CITY SMALL CITY SMALL CITYLARGE CITY
= Station
The proposed network system provided a direct connection service without transfer for each
OD pair even in case of a small city if the demand is sufficient for its economic operation.
13
Hanyang University
Process of the heuristic optimized network design
The set of major corridors were combined
all together into as a whole network, and it
was refined and simplified with
professional knowledge.
Step 1
Selecting candidate sets
of cities to be served
Step 2
Running minimum spanning
tree(MST) algorithm and
finding a set of major corridors
The alternative sets of cities, which will be
served by Hyperloop, was selected by
ordering cities from the biggest population.
The MST analysis was performed for each
candidate set of cities to find a cost-
minimized network. Then, a set of major
corridors was selected heuristically.
Step 3
Combining all of major corridors
and refining and simplifying the
combined network
14
Hanyang University
Cities of the top 60 in the population, South Korea(Selecting candidate sets of cities )
GyunggiProvince
GangwonProvince
ChungcheongProvince
GyungbukProvince
Jeon-laProvince
GyungnamProvince
Gangneung
Ulsan
Busan
Daegu
Daejeon
Gwangju
IncheonSeoul
• The cumulated populations of
the top 30 and the top 60 cities
in aspect of the population are
74.8 % and 88.7 % of the total
population of the South Korea
respectively.
• In this study, 60 cities were
selected as the largest number
of candidate cities for the
Hyperloop service that can
serve about 90 % of the total
population.
15
Hanyang University
Concept of minimum spanning tree (MST)
𝑀𝑖𝑛. 𝑧 =
𝑖𝑗∈𝐸
𝑐𝑖𝑗𝑥𝑖𝑗
𝑆𝑢𝑏𝑗𝑒𝑐𝑡 𝑡𝑜
𝑖𝑗∈𝐸
𝑥𝑖𝑗 = 𝑛 − 1
𝑖𝑗∈𝐸:𝑖∈𝑆,𝑗∈𝑆
𝑥𝑖𝑗 ≤ 𝑆 − 1 ∀𝑆⊆𝑉
𝑤ℎ𝑒𝑟𝑒 𝑥𝑖𝑗 ∈ 0, 1 𝑎𝑛𝑑 𝑐𝑖𝑗 = cost of link 𝑖𝑗
https://en.wikipedia.org/wiki/Minimum_spanning_treeMathematical formulation
The MST problem is to find a tree that is the minimum total cost of links
connecting all the nodes in a given graph.
16
Hanyang University
Objective function used in this study
𝑀𝑖𝑛. 𝑧 =
𝑖
𝑗
𝛼 𝑉𝑖𝑗 + 𝛽 𝐶𝑖𝑗 𝑥𝑖𝑗
𝛼 + 𝛽 = 1𝑤ℎ𝑒𝑟𝑒 𝑉𝑖𝑗 = 1 −𝑇𝑖𝑗
𝑚𝑎𝑥 𝑇𝐼𝐽,
𝑇𝑖𝑗 ∶ 𝑁𝑢𝑚𝑏𝑒𝑟 𝑜𝑓 𝑡𝑟𝑖𝑝𝑠 𝑏𝑒𝑤𝑒𝑒𝑛 𝑐𝑖𝑡𝑦 𝑖 𝑎𝑛𝑑 𝑐𝑖𝑡𝑦 𝑗 𝑝𝑒𝑟 𝑑𝑎𝑦
𝐶𝑖𝑗 =𝑑𝑖𝑗
𝑚𝑎𝑥 𝑑𝐼𝐽, 𝑎𝑛𝑑
𝑑𝑖𝑗: 𝑑𝑖𝑠𝑡𝑎𝑛𝑐𝑒 𝑏𝑒𝑡𝑤𝑒𝑒𝑛 𝑐𝑖𝑡𝑦 𝑖 𝑎𝑛𝑑 𝑐𝑖𝑡𝑦 𝑗 (km)
Distance of links are directly proportional to the infrastructure construction
cost. Therefore, the above objective function is intended to simultaneously
reflect travel demand and construction cost in the network design.
17
Hanyang University
MST analysis for candidate sets of cities
10 cities 13 cities 16 cities 20 cities 25 citiesTotalcost:3.795 Totalcost:4.1978 Totalcost:5.5619 Totalcost:6.9814 Totalcost:9.0771
30 cities 35 cities 40 cities 50 cities 60 citiesTotalcost:11.4901 Totalcost:13.4482 Totalcost:15.8013 Totalcost:20.7758 Totalcost:25.5511
18
Hanyang University
Finding a set of major corridors heuristically
Overlapped MST results of the representative candidate sets
Desire line of OD travel demand
Overlapping the results of the MST analyses for several candidate sets of cities graphically
and identifying the corridors that are used redundantly in serval candidate sets. The study
also considered travel demands of OD pairs with the desire lines.
19
Hanyang University
A schematic and conceptual set of corridors
①
②
③
④
②
①
③
④
Overlapped MST results of the representative candidate sets
Desire line of OD travel demand
It is worth to note that relatively large number of travel demand are concentrated on
the corridor 1 compared to the other corridors.
20
Hanyang University
The selected set of six corridors
West seaNS Corridor
North EW Corridor
East sea NS Corridor
Busan NS Corridor
Gwangju NS Corridor
SouthEW Corridor
1. North EW corridor
2. West-sea NS corridor
3. Gwangju NS corridor
4. Busan NS corridor
5. East-sea NS corridor
6. South EW corridor
21
Hanyang University
MST analysis for each corridor independently
4. Busan NS corridor
3. Gwangju NS corridor1. North EW corridor 2. East-sea NS corridor
6. South EW corridor5. West sea NS corridor
22
Hanyang University
Combining all of major corridor’s MST results
to a national-wide composite network
4. Busan NS corridor
3. Gwangju NS corridor1. North EW corridor 2. East-sea NS corridor
6. South EW corridor5. West sea NS corridor
MST results for each corridor A combined network
23
Hanyang University
Network refinement and simplification
for the Seoul metropolitan area
Busa
n
NS C
orr
idor
Westcorridor
Mid.corridor
Eastcorridor
24
Hanyang University
National-wide network refinement and simplification
Final proposed national-wide network
25
Hanyang University
Multinomial Logit Model for a mode choice analysis
𝑃𝑚 =exp 𝑉𝑚
σ𝑘 exp 𝑉𝑘
Where Pm = probability to choose mode m
Vk = a utility function of the alternative mode k
𝛽0𝑘 = mode specific constant for mode k
𝛽𝑛𝑘 = a parameter for the nth explanatory variable of mode k
𝑉𝑘 = 𝛽0𝑘 + 𝛽1 𝑇
𝑘 + 𝛽2 𝐶𝑘
Logit model A utility function
𝑉𝑘 = 𝛽0𝑘 + 𝛽1 𝑥1
𝑘 + 𝛽2 𝑥2𝑘+ . . . . .
This study used following utility function that the Korean government officially
distributed for feasibility study of transportation infrastructure construction plan.
where 𝑇𝑘 = travel time of mode k
𝐶𝑘 = travel cost of mode k
26
Hanyang University
Results of mode choice analysis and
the share of Hyperloop
Seoul
Daejeon
Daegu
Busan
27
Hanyang University28