THE USE OF ROPE-FREE MULTIDIRECTIONAL ELEVATORS IN
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A9
Paper #8095
Disclaimer—This paper partially fulfills a writing requirement for first year (freshman) engineering students at the University
of Pittsburgh Swanson School of Engineering. This paper is a student, not a professional, paper. This paper is based on publicly
available information and may not provide complete analyses of all relevant data. If this paper is used for any purpose other
than these authors’ partial fulfillment of a writing requirement for first year (freshman) engineering students at the University
of Pittsburgh Swanson School of Engineering, the user does so at his or her own risk.
THE USE OF ROPE-FREE MULTIDIRECTIONAL ELEVATORS IN
SKYSCRAPERS
Rachel Dancer, rjd62@pitt.edu, Sanchez 3:00, Julia Jones, jaj136@pitt.edu, Mandala 10:00
Abstract— With the continuing effects of urban migration, Kate Ascher, the Milstein Professor of Urban
engineers, architects, and builders are being challenged to Development at Columbia University Graduate School of
make cities denser and more efficient. By the end of the Architecture, estimates that elevator wait times in New York
century, seventy percent of the world will live in cities [1]. City office buildings “ranging from 20 to 25 seconds are
These challenges can be overcome by building taller and more considered good, while those between 30 and 35 seconds are
economical buildings. However, current elevator technology generally considered unacceptable” [9]. A twenty second wait
impedes the efficient construction and use of skyscrapers. The time may not seem like a significant amount of time on paper,
implementation of rope-free multidirectional elevator systems but in a nineteen-story office building (the average floor
could solve these challenges by reducing elevator wait times, number in New York City), each second wasted can ultimately
optimizing costs, and increasing energy efficiency. lead to a human traffic jam in a busy lobby [10]. The crowding
These systems, named MULTI, are powered by associated with high traffic areas leads to worker irritation and
electromagnetic induction that causes magnetic levitation, aggression, and is often “associated with stress and affects
which moves the elevator cars side to side as well as up and workplace satisfaction” [11]. As a result, it is recommended
down [2]. This method removes limitations caused by ropes, that faster and more efficient elevator systems be designed to
which restrict building heights and slow down the elevator car mitigate these problems.
[3]. It also allows multiple elevator cars to fit into one shaft Elevator inefficiencies reach far beyond those who ride
and move throughout the building in a loop. Users will them on a daily basis. As buildings grow higher, elevators must
experience shorter wait times and owners can better maximize service a greater number floors and people. In most
their available floor space [4]. These systems can also reduce skyscrapers, this means that a large number of elevator shafts
a buildings electric bill by up to 60% [4]. and cars are required in the building. However, the installation
In this paper, we intend to analyze how the MULTI of elevator banks has prominent impacts on the profitability
Elevator compares to traditional elevator systems, and how it and usability of a skyscraper. Ascher asserts that “each
could be implemented in order to make the production and use additional bank of elevators reduces the floor area available for
of skyscrapers cheaper, more efficient, and more convenient. rent or sale-thus pushing down the revenue potential for the
building” [9]. As the number of elevators in a building
increases, the square footage of each floor consumed by
Key Words—Elevators, Linear Induction, Magnetic elevator shafts rapidly increases, while space available for rent
Levitation, Skyscrapers, Transportation Engineering begins to dwindle.
Ken Yeang, a renowned architect and ecologist, provides
CURRENT ISSUES IN URBAN LIVING guidelines for acceptable space use in skyscrapers. He asserts
that “net-to-gross floor area should not be less than 75%, while
Sustainably Accommodating a Growing Urban 80% to 85% is considered appropriate” [13]. Net-gross-floor
Population area (also known as space efficiency) is “simply defined as the
ratio of NFA to GFA” [14]. NFA, formally known as the net
The traditional elevator creates a variety of inefficiencies floor area, is the “actual occupied area not including
for building users, building owners, and building designers. unoccupied accessory areas such as corridors, stairways, toilet
These unsustainable inefficiencies are both time wasting and rooms, mechanical rooms and closets” [15]. GFA, known as
cost prohibitive, leading to buildings that inconvenience users gross floor area, is “the floor area within the inside perimeter
and limit the designers and building owners. In a study of the exterior walls of the building under consideration…
conducted by IBM in 2010, the “cumulative time that office without deduction for corridors, stairways, closets, the
workers spend waiting for elevators in the past 12 months thickness of interior walls, columns or other features” [15]. A
totaled 92 years” across sixteen metropolitan areas in the visual representation of how a floor is broken into different
United States [8]. areas can be seen in Figure 1. In this figure, the GFA is initially
University of Pittsburgh Swanson School of Engineering 1
Submission Date 03.31.2018
Rachel Dancer
Julia Jones
divided between NFA and a structure area. This structure area resonance and lack of damping make elevators vulnerable to
is where the space taken up by elevator shafts is categorized. damage caused by vibration.
Rope-swing, a phenomenon that occurs when an elevator
cable reaches its natural frequency, causes the elevator cable
to vibrate quickly, resulting in unusual elevator movement and
damages within the elevator shaft [3]. However, rope-swing
does not affect many people in their daily life because of
Newton’s 3rd Law, which states that an object at rest stays at
rest until a force is applied [3]. This means that something
needs to set the cord into motion. Waves in ropes of elevators
in tall buildings can be induced by heavy wind or seismic
movement. Wind is less of an issue because its effects are less
extreme and more predictable [3]. Earthquakes are recorded to
cause a lot of damage in mechanical elevators. Typical damage
caused by rope swing in elevator shafts includes jamming of
Figure 1. [15] elevator cables, deformation of rails, and derailing [3]. In
This is a diagram that breaks down the total space on a 2011, surveys were done after the Chuetsu earthquakes in
floor of a building into different categories, such as usable Japan to quantify damages, and it was found that “about 24%
area, structural area, and mechanical areas. of the damage [in the Tohoku area] was due to ropes colliding
with machinery or elevators becoming stuck.” [3]. This is
Ultimately, increases in the number of elevators results significant because it demonstrates that cables on elevators can
in decreases in NFA, leading to an overall decrease in space have destructive consequences if elevators are installed in
efficiency. Because skyscrapers are “built to make money” [9], buildings in seismic zones.
high space efficiency is crucial to maximizing rentable floor Since there are few viable solutions to this problem,
space and making a skyscraper profitable. Civil engineers and engineers have found that the best way to fix the problem is to
architects must strive to develop elevator systems that eliminate it completely. Instead of increasing the damping and
maximize usable floor space while simultaneously attempting making a long tense rope, engineers use systems like sky
to provide sufficient amounts of elevators for building users. lobbies to put limits on rope lengths to reduce the possibility
of resonance. However, a solution that eliminates the rope
Elevators as a Size Constraint of Skyscrapers completely could ultimately be a better, more cost-efficient
method of fixing the resonance problem.
Traditional elevators are one of the factors that put size
limits on skyscrapers. While they are not the only factor, and CURRENT ELEVATOR TRANSPORTATION
elements of design such as soil strength and building materials SYSTEMS
have a strong effect on the height limit, elevators are a large
component of deciding a height cap for a building [4]. Zoning
Traditional elevators are cable driven, traction-based cars that
traverse a track vertically to move people and cargo from floor In current skyscrapers, architects and engineers have
to floor. The car is suspended by a steel cable that is connected created elevator transportation systems using zoning and sky
to a pulley and supported by a counterweight [16]. lobbies [17]. With zoning, each elevator does not have to stop
All objects are vibrating to some degree all the time, but at every floor. As can be seen in Figure 2, each elevator is
the nature of this design and the tension on this rope makes instead assigned a range of floors to service. This means that
elevators vulnerable to hitting their resonance frequency. rather than one elevator lifting passengers going to a wide
Vibration itself is not a bad thing. The issue occurs when range of floors, passengers are instead sorted into the elevator
objects reach their natural frequency, or resonance, because the bank targeted to their destination. For example, in Figure 2,
amplitude of the vibration is much greater [25]. The natural Elevator #3 is assigned Zone 3, meaning that it is responsible
frequency of the rope is length dependent, but the length of the for transportation within Zone 3 (floors 10-15) and to Zone 3
cable is constantly changing [16]. This makes it hard to control from the ground floor. This significantly reduces the number
whether or not a rope will reach its natural frequency [3]. In of stops an elevator must make on each ascent and descent.
addition, elevator ropes have very low damping properties. Unfortunately, zoned elevators lose their efficiency in mega-
Damping properties decrease the amplitude of a wave with tall buildings with upwards of sixty floors and high occupancy
time [3]. Without damping, waves would continue oscillating amounts. This is because the number of zones necessary to
indefinitely. There is no known way to increase the damping maintain efficiency increases as height rises, necessitating
since the length of the rope is variable. Overall, the risk of more elevators. In addition, the number of occupants in a
building grows with height, meaning more elevators will be
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needed to service each floor in order to accommodate the
increased population.
Figure 3. [17]
This is a diagram that depicts how sky lobbies work in a
building. Several elevators are given cables long enough
to reach a certain floor. This floor, referred to as the sky
lobby has another bank of elevators, unconnected to the
first set, that are responsible for transporting passengers
to the higher floors of a building.
Figure 2. [17]
This is diagram depicts how zoning works in a building. EVOLUTION OF ELEVATORS LEADING UP
Each elevator is assigned a zone to be responsible for. TO MULTI
Each zone consists of several floors. In this figure, each
zone is 5 floors. Although the writings of Vitruvius reveal that “the
Greek mathematician Archimedes created a primitive
Sky lobbies, on the other hand, break up elevator travel elevator in 236 B.C.”, the elevator did not become integrated
distances by creating separate elevator shafts at various points into common society until Elisha Graves Otis “invented a
throughout the building. This shortens the length of the safety brake” in 1852 [7]. The safety break protected users
elevator cables, significantly reducing safety issues associated from falling to the ground if the hoisting rope broke by
with cables and resonance frequency. As explained by João ensuring that “a spring would operate pawls on the car,
Valente in his Final Thesis for the Degree of Master in Civil forcing them into position with racks at the sides of the shaft
Engineering, another “advantage of the sky lobby is the core and suspending the car in place” [7]. Otis’ safety brake
optimization since all elevators do not have to serve the entry marked the beginning of the twentieth century’s global
level. The upper local zones are stacked on top of one another, skyscraper race.
so the elevator shafts, generally occupy the same "footprint" as Also, an important milestone in elevator history is the
the local zones below” [17]. The stacking of elevators in the Paternoster Elevator, invented by Peter Hart in 1882 [15]. The
sky can be seen in Figure 3. Although space optimization is an Paternoster Elevator, which is pictured in Figure 3, consists of
important feature of elevators, particularly with respect to cost, several elevator cars moving in a continuous loop throughout
the inconveniences that sky lobbies pose to building users must a shaft. The Paternoster system is “considered the most
be acknowledged. Figure 3 demonstrates clearly that users effective transportation system”, but unfortunately it is “very
who wish to travel to the top of the building are hindered from limited in height, speed, and safety”. Consequently, the system
quick and easy transportation by a forced layover between two has been out of common use for several decades [15].
elevator systems. As a result, smooth and continuous
transportation within the sky lobby elevator system is
disjointed and inefficient.
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tracks, these new elevator cars can move up and down and left-
to-right. This allows elevator shafts to deviate from the
conventional vertical-only shaft, and expand into multi-
directional pathways.
Figure 4. [18]
This figure is a diagram of the Paternoster Elevator that
would later become the inspiration for MULTI. The
elevator cars in this system all fit into one shaft, and are
demonstrated to rotate through a loop in the diagram.
OVERVIEW OF MULTI
Figure 5. [21]
More than 150 years later, the elevator has become an This image is a computer rendering of the
integral part of everyday life. From office workers to arrangement of a MULTI system in a tall building. In the
apartment residents, many people rely on elevators to safely, image, blue elevator cars move throughout a continuous
efficiently, and conveniently transport them. However, the orange elevator shaft.
demand facing elevators has changed drastically since the first
commercial elevator. Now, elevators serve hundreds of people HOW MULTI WORKS
every day. In addition, the increasingly tall heights of
skyscrapers have created a dependency on elevators. It is
completely impractical to expect someone to climb hundreds Ropeless elevators work due to magnetism and linear
of stairs to arrive at their destination every day. Despite these motor technology. In a conference paper for the Council on
changes, elevators “haven’t changed much in the past 160 Tall Buildings and Urban Habitat, Markus Jetter, the Head of
years” [19]. To ensure reliable vertical transportation in the Product Development, and his partner, Stefan Gerstenmeyer,
future, major innovations in elevator design are vital explained that the upward movement without a pulling force is
Popularly coined as the “Willy Wonka Elevator”, made possible “by applying the linear motor technology of the
MULTI is a new elevator technology that differs significantly magnetic levitation train, Transrapid, to the elevator industry,”
from traditional elevators [19]. Inspired by the Paternoster [15]. The Transrapid is a high-speed train that uses magnetic
Elevator system, MULTI was first prototyped in 1998 by Dr. levitation to hover above the track, which eliminates all
Jessenberger at the University of Aachen [15]. Multi replaces friction, and it implements linear motors to motivate the
ropes with linear motors to create “a successful circulating vehicle [19]. Magnetic levitation is a result of
elevator system” [15]. MULTI has come a long way since its electromagnetism and linear motor technology.
initial prototype in the late 1990’s. In 2014, ThyssenKrupp, a Applying the mechanisms behind the Transrapid to
German industrial company well known for its innovative elevators means turning it on its side. This involves combining
elevator technologies such as AGILE, TWIN, and MRL, the levitation and propulsion devices because they do the same
announced its plans to create a cable-less elevator technology thing. A big component of the MULTI elevator is the fact that
[20]. it is not limited to a vertical track. The interlocking exchange
As can be seen in Figure 5, MULTI is unique from system in the tracks of the elevator shaft does not disrupt the
traditional elevator systems in that it consists of multiple magnetism in action. Electromagnetism, linear induction, and
cordless elevators, all rotating through a single shaft. Because interlocking are the three main components of MULTI that
it forgoes cords for linear motors and magnetic levitation
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allow it to operate without ropes and run in multiple directions shows that this allows the car to support more mass while
with multiple cars per shaft. moving at the same acceleration, as well as resisting a constant
gravitational acceleration [24]. This is where handling capacity
Electromagnetism and elevator materials come into play. It can support more
people as well as the weight of the actual car if the strength of
Magnets have properties that can give different types of the super conductor is strong enough. ThyssenKrupp has
material the ability to produce a force, and that force can be reported that MUTLI can hold up to eight people in an elevator
harnessed to do work [22]. This work can be used in propulsion car [15].
of ropeless elevators.
This involves activating ferromagnets. Ferromagnets are
metals that do not have magnetic properties on their own. Due
their atomic structure, the electrons in the metals can easily
align with an existing magnetic field. This phenomenon results
in an induced magnetic field, given off by the ferromagnet,
which makes it act like any permanent magnet would [23].
Electromagnets are made when a moving current is introduced
to a ferromagnet. Adding an electric current to a ferromagnetic
is another way to align the electrons and therefore induce a
magnetic field. This is how electromagnets gain their magnetic
force: a current is sent through a ferromagnet using electricity.
Electromagnets have advantages over standard permanent Figure 6. [24]
magnets because the strength is dependent on the strength of This image provides a visual for the equations and laws of
the current, so the attraction has the ability to be turned on and physics described. In order from top to bottom, Ohm’s
off as needed [22]. Electromagnetism is the interaction that Law, Biot Savart Law, and Lorenz’s Force Equation, and
allows magnetic levitation to be possible. Newton’s 2nd Law are shown.
In summary, induction can occur by introducing an
existing magnetic field or an electric current. Both require a Linear Motor
form of work, but adding a field involves converting
mechanical energy, whereas running a current uses electricity Linear motors are used to move the cars through the
as its form of energy. This concept applies to a bigger scale shafts of ropeless elevator. The engineers that created MULTI
than elevators. Electricity powers lights and technology in have not directly revealed which type of linear motor they
houses and buildings among other things [23]. used. With research, the only two plausible linear motors are
The two methods of creating a force using an either a synchronous linear motor or a linear induction motor.
electromagnet can be combined by using the concept of Multi had a patent released that said their linear motor does not
superconductors. Superconductors are made by manipulating use iron for the permanent magnet, and linear synchronous
electromagnets with the goal of giving them an extremely motors require permanent magnets and prefer soft iron. This
strong magnetic field [22]. To do this, ferromagnets are cooled data point rules out linear synchronous motors. From this we
to temperatures so extreme that they lose their electric can conclude that MULTI uses linear induction motors [26,
resistance [23]. With little resistance, and a constant voltage 27].
from the power supplier, the ratio of current increases [22]. Electromagnetic induction, as previously explained, is
Using the laws of magnetism in Figure 6 to understand used to make an AC motor. AC motors use similar concepts to
this phenomenon, it is clear to see that resistance has a large linear induction motors. Electrical energy is converted to
impact on force. As proven by Ohm’s law, when the amount mechanical energy through the AC motor, and the mechanical
of voltage supplied is constant, the resistance is inversely energy makes a mechanism spin. The type of mechanical
proportional to the current [23]. Substitute Ohm’s Law into the energy needed for linear induction motors is different, but the
Biot-Savart Law and the Lorenz’s Force equation to see that underlying principles are similar. Explained simply, linear
current is directly proportional to magnetic field and force. So, induction motors are AC motors transformed from their rotary
for instance, if the resistance in a ferromagnet was decreased shape to redirect the energy in a linear fashion [28]. Since the
to be 100 times smaller, the magnetic force and field would energy is not limited to the rotary geometry, the motor can give
increase to be 100 times larger than before the resistance a levitation effect.
changed. This extra force is what makes magnetic levitation The technology that MULTI uses is comparable to the
possible [22]. technology in maglev trains, like the Transrapid [15]. Since the
In the context of the elevator, this means that since the Transrapid moves strictly horizontally, it needs different
engineers will use superconducting magnets instead of a mechanisms to provide levitation and propulsion. The primary
standard electromagnet to control the car, they can control cars focus of the motor on the elevator is to make it follow the track
using a greater force. Referencing Figure 6, Newton’s 2nd Law
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so it can rise vertically. This combines the propulsion and
levitation mechanism. Concepts of traffic engineering are required as well as
The propulsion is not a continuous pushing force on the mechanics to explain how the interlocking system inside of
elevator. For the car to move, it requires a combination of ThyssenKrupp’s MULTI elevator works. The hardware and
positive forces to push the train forward and negative forces to software required to allow multiple cars to move in different
pull the train forward. As shown in Figure 7, these positive and directions within the elevator shafts is complex. The algorithm
negative attractions alternate. Magnets have north and south required for these cars to avoid collisions requires intel on the
poles. Opposite poles attract and like-poles repel each other. routes these elevators need to take to get the most people to
[26]. See Figure below. It depicts the technology used to make their destination as quickly as possible. The interlocking
maglev trains run, but the same concepts can be applied to mechanism allows cars to change directions and takes care of
elevators. the mechanical aspect of trafficking these elevators. [15]
Interlocking is an important design aspect to touch on
because it allows the elevators to break out of the strict
verticality and move in any direction. To visualize
interlocking, imagine trains changing direction at an
intersection on a railroad. The rail rotates. This is usually with
the help of a railway turntable, which is pictured in Figure 9.
Trains drive to the center and have 360 degrees of rotation to
navigate between [29]. In MULTI elevators, the system that
changes the direction of the car is comparable to a railway
turntable turned on its side. Referencing Figure 10, it can be
confirmed that the systems are very similar in MULTI. On
Figure 7. [25] either side of the elevator car, there are mechanisms in place
This image explains that alternating poles on maglev to guide the car, and when they enter into an intersection where
trains cause the forward propulsion. Elevator technology they can turn, the outside component rotates to allow it to move
is comparable to trains. into the new direction. The car remains upright as it goes
through the direction change. This mechanism allows long
Linear motors are effective in creating magnetic distance horizontal travel by getting the car out of the one
levitation in MULTI’s ropeless elevators. Figure 8 shows that dimension and providing it the option to move horizontally
the motors in the actual device are on the inside the shaft, [15].
between the wall and the car. Because of the superconductors
required to make magnetic levitation as strong as possible, it is
extremely cold in that space. Pictured below is a top view of
the elevator shaft of MULTI [23,26].
Figure 9. [29]
This diagram is produced to explain how railway systems
turn. A popular component of the interlocking system on
Figure 8. [26] trains is the turntable design. Trains drive to the center
This is the patent for the first maglev elevator, which was and have 360 degrees of rotation to navigate between.
created by ThyssenKrupp in 1998. This is a top-view of
the elevator shaft.
Interlocking
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estimates [35]. The likelihood of underestimation in the energy
consumption of elevators makes the reduction in necessary
power by MULTI elevators an even greater asset for building
owners. Ultimately, the money saved in utilities costs from
MULTI’s energy efficiency and the money generated by
maximizing the amount of rentable space will increase the
profit of building skyscrapers with more sustainable
equipment.
BENEFITS TO BUILDING USERS
Figure 10. [30] The primary benefit MULTI poses to building users is a
This image is an explanation provided by ThyssenKrupp decrease in wait times for elevators. As demonstrated in Figure
to show how the turntable interlocking systems work. 11, the time it takes for a double-decker elevator car to arrive
at its target floor gets substantially larger as building height
increases. However, the time it takes for a MULTI elevator car
BENEFITS TO BUILDING OWNERS to reach its target remains constant, and is always lower than
the double decker elevator. This is because the time it takes for
MULTI’s space and money saving features have the MULTI elevators to move to their target floor is not dependent
potential to save building owners thousands of dollars. For on the height of the building, but rather on “velocity, number
example, MULTI elevators have smaller shafts than traditional of stops, door times, and highest reversal floor” [15]. Each
elevators and can “increase a building’s usable area by up to MULTI elevator makes a constant amount of stops on every
25%” [31]. This is significant because “current elevator- ascent and descent, so there is no way to vary the time it takes
escalator footprints can occupy up to 40% of a building’s floor to get to each destination.
space, depending on the building height” [31]. Because the
purpose of skyscrapers is to generate profit through leases and
rentals, every square foot of usable space is important to
increasing profit.
One issue that ThyssenKrupp does not address is that
traditional elevators offer a large component of structural
support to the core of tall buildings, and some engineers have
concerns that changing the elevator will take away from the
structural integrity of the building [32]. In skyscrapers, a large
part of the structural support within the core comes from the
elevator shaft [13]. This is because they are reinforced with
steel to add the support to the building because it is a
convenient location structurally. The concern lies within the
possibility of taking out the continuous vertical elevator shaft.
The selling point of MULTI is that users are not limited Figure 11. [15]
to riding in the direction that tall buildings are erected. This This image depicts the amount of time it takes before an
issue can be resolved by leaving the users the option to go all elevator arrives at its assigned floor at different building
the way to the top of the building by keeping the continuous heights. The bars on the left show the times for MULTI,
shaft, and adding horizontal options in addition to that. If this and the bars on the right show the times for double
is ever not the case, engineers can make a skyscrapers core decker elevators.
independent from the elevator.
In addition, researchers at ThyssenKrupp have found that CURRENT AND FUTURE APPLICATIONS
MULTI “requires dramatically lower peak power- as much as
a 60-percent reduction when compared to conventional Immediately after ThyssenKrupp “first announced the
elevator systems” [31]. This is significant because “elevators idea of a maglev elevator way back in 2014”, it began
account for 3 to 8% of electricity consumption in buildings” developing a functional prototype of MULTI. [36]. In 2015,
according to the Italian National Agency for New the first fully functioning 1:3 scale model of MULTI was
Technologies, Energy and Sustainable Economic publicly unveiled at the Innovation Center in Gijón, Spain
Development [34]. Furthermore, researchers from SVM [37]. This model of MULTI, as seen in Figure 12, proved to
Associates, an engineering consulting company, discovered the public that a ropeless elevator was possible, and laid the
that “elevators were found to burn 16% to 36% more energy in foundation for the larger and more complex prototype being
real-world use” than they were predicted to consume in developed in Rottweil, Germany.
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Julia Jones
ThyssenKrupp is also making vigorous efforts to push
MULTI into the public transportation sector in the future. The
company hopes that MULTI can be used to integrate
skyscrapers with underground metro stations in order to make
entry and exit out of the station, as well as horizontal
transportation within it, more efficient as population increases
begin to create strenuous demands on stations [30]. MULTI
would also make metro stations more accessible to wheelchair
and crutch users, who are often unable to conveniently enter,
navigate throughout, and exit metros because of a lack of quick
and conveniently located elevators.
PROBLEMS
Cost
Currently, no public information about the cost of a
Figure 12 [37] MULTI elevator system has been published. Speculators such
This image depicts “two ten meter shafts and four cabs” as Jamie Condliffe from the MIT Technology Review guess
moving along a MULTI system in a loop like fashion [37]. that MULTI will “cost as much as five times more than a
standard lift system” [36]. Despite high price estimates such as
In 2017, ThyssenKrupp publicly unveiled its state of the Condiffe’s, MULTI’s ability to drastically improve space
art elevator test center in Rottweil, Germany. Within the tower, efficiency and reduce energy consumption could create long
“the MULTI system is installed in three of the twelve tower term financial benefits in buildings taller than three hundred
shafts” [36]. The test tower, seen in Figure 13, is known as the feet, where elevator costs will already be sky-high. As prices
Aufzug Testturm and is currently the “largest innovation are publicized, engineers and architects might have to sacrifice
center for elevator technology in Germany” [38]. Because the long-term efficiency for affordability by installing cheaper and
Aufzug Testturm also boasts the highest public viewing more traditional elevators. In order to truly become the
platform in Germany at a height of 232 meters, the prototype elevator of the future, ThyssenKrupp may have to develop
is the first opportunity for everyday citizens to interact with plans to reduce the costs of MULTI.
MULTI [36].
Retrofitting
ThyssenKrupp needs to design an efficient, convenient,
and cost-effective plan to install MULTI in preexisting tall
buildings. Karen Kroll, a writer for Facilities Net, a popular
facilities maintenance magazine, estimates that “elevator
modernization could take nearly a year… [and that] the
elevator will be out of commission for about 15 to 16 weeks”
[40]. Furthermore, simply modifying traditional elevators with
more up-to-date equipment such as cars, controllers, hoists,
and door operators “can easily hit six figures” [40]. This
implies that installing MULTI, a system already rumored to
Figure 13 [38] “cost as much as five times as five times more than a standard
This image depicts the ThyssenKrupp test tower lift system”, might not be a cost-effective technology to
in Rottweil, Germany. This is where much of the testing implement in a pre-existing building [40]. However, there is
for MULTI occurs. still possibility for ThyssenKrupp to develop cost-lessening
methods to be used to retrofit preexisting tall buildings.
The first customer lined up to install MULTI is OVG
Real Estate, who wants MULTI to be implemented into its Jurisdiction
brand new, eco-friendly building, the East Side Tower in
Berlin [39]. The project does not have a completion date yet, Rick Sayah, the vice president of the elevator consulting
but the future of MULTI depends on ThyssenKrupp’s ability firm Van Deusen & Associates, has expressed concerns about
to successfully implement it into an actual building. the regulation of MULTI, especially when it is applied to the
public transportation sector. Because MULTI will serve as
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Julia Jones
more than just a mere elevator in the public transportation 390: 164-191. 2017. Accessed 1.28.2018. https://ac.els-
sector, its true role is blurred between an elevator and “a cdn.com/S0022460X16306228/1-s2.0-S0022460X16306228-
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3.25.2018.
ACKNOWLEDGEMENTS
10Rachel Dancer
Julia Jones
We would like to acknowledge Thesaurus.com for
always providing us with reliable word ideas throughout the
duration of this paper. In addition, we would like to thank our
conference chair and co-chair for taking the time out of their
schedules to read and edit our paper. Finally, a massive thanks
to those who helped teach us concepts about the physics
concepts needed to write this paper.
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