A test of the Mobile Bridge® Version 4.0 (MB4.0) over a real river demonstrated its viability for practical use. During the test, the bridge was set up without any foundation work, and a vehicle could easily travel across it. This was achieved safely with very few people and without any problems. The MB4.0 viability test results were presented at a symposium of the Japan Society of Civil Engineers (JSCE) on June 23, 2015, by Dr. Ichiro Ario, Ass. Professor at the Institute of Engineering, Hiroshima University.
Background of developing MB:
Natural
disasters include earthquakes, floods, tsunamis, and landslides. They
can occur anywhere in the world. The damage caused by such disasters to
infrastructure such as bridges necessitates a rapid response to rescue
survivors and deliver medical care to the injured within a new set of
localized constraints.
1. New secondary hazards caused by localized damage can impede any rescue operations.
2. This raises the question of what useful activities can be performed in the immediate aftermath of a major natural disaster.
3.
In many disasters, urgent medical attention can be delivered to injured
survivors only if a new bridge is constructed or deployed rapidly.
4. In certain situations, an emergency bridge may be needed even where no professional structural engineers are available.
We propose a new type of foldable/deployable bridge with a scissor mechanism called Mobile Bridge (MB). MB4 can be deployed and folded quickly, and it therefore provides highly efficient construction and easy transportation.
In
the aftermath of a natural disaster, rapid repair of infrastructure is
required. A fast response will significantly improve disaster recovery
efforts. Dr. Ario of Hiroshima University proposed a new concept in
bridge innovation.
1. Rapid response will help provide urgent medical aid to injured survivors.
2.
Any rescue technology should have a low level of complexity and high
degree of resilience to enable its deployment by any persons in a
locality.
3. MB uses a patented technology with a scissor mechanism for deploying an emergency bridge system set within a modular design.
4.
MB is a compact transportable bridge system; it is suitable for
transportation using a car trailer, and it can be easily deployed and
folded using its scissor mechanism.
5. This bridge system has a
completely novel design and offers extraordinary performance that
cannot be matched by the older block assembly approach for bridges.
MB can be deployed in a wide range of areas and has numerous applications. Many existing bridges are in a poor state of repair owing to poor maintenance and overuse. Smaller bridges can be kept operational using MB. This affords the advantage of keeping bridges fully operational without interrupting traffic and causing further damage to the existing bridge by traffic.
Background of development based on Origami:
MB
has a scissor-like structure that is connected to the main structural
members to form an gXh shape; this enables expansion and contraction
while retaining strength. The idea for this new bridge comes from
academic studies on buckling based on Origami (Japanese traditional
paper craft), which has attracted the attention of researchers in space
development and other fields.
Dr. Ario developed MB4.0 as a type of robotic bridge by improving its mobility and functionality and decreasing its weight. Therefore, MB4.0 has become more transportable and easier to set up at temporary construction places without any foundation construction or crane operations. As a result, it is also less costly.
MB4.0 is the worldfs fastest, largest, strongest, and lightest expanding temporary bridge. In addition, it is the fastest to set up. Because the bridge and its lanes are expanded simultaneously, the bridge is ready for traffic as soon as it is fully expanded. From the arrival of MB4.0 on site to its full expansion only takes around one hour. The actual extension time is only around five minutes. This is especially important for time-sensitive situations during a disaster.
Dr. Ario stated that gFrom this test of a new bridge concept, the next generation of bridge technology starts on a new stage in the field of bridge engineering. It is possible to use a real deployable and smart bridge with a scissor-type bridge system using this structural theory. I will further promote the development and evolution of MB4.0 in the future. Making MB stronger, longer, lighter, more compact, and quicker to set up will promote the development of infrastructure construction technology in general.h
Notice:
Although this developing story of MB4 may not be perfectly
expressed the history of Mobile bridgeTM based on Origami idea
with/skills in scientific viewpoints. Will you understand the meaning of the developing story why we develop
this type of bridge by scientific and engineering skills?
Topic
0. Kobe earthquake 1995, background my research motivation
When I was 28 age
in1995, there was Kobe earthquake, I grew up near Kobe before then. I have just
studied the book of ``Instabilities and Catastrophes in Sciences and
Engineeringh by J.M.T.Thompson and ``A General theory of Elastic Stability g by
J.M.T.Thompson and G.W.Hunt, so I had investigated many damaged infrastructures
in Kobe with academic viewpoints.
A singular point(s)
in physics is so significant to be recognized ``change of catastrophe in
materials and/or structures such as a bridge, a tower, infrastructure etc. However,
if we carried out an experiment of the real size structure, it would be very
experience. Now, we can use the simulation by computing methods. But, it looks
difficult for the forecasting of an earthquake when/where/how size happens. It
looks complex even though we can use science tools. Origami is so useful for us,
it is taught how to fold/how strong/folding patterns by under nature, in
physics of the scientific view.
Topic 1. From MECHANICS of ORIGAMI(Ü) in 2003 at Univ. of Bath in UK
The cellular buckling on a cylinder
made by Origami (folding paper) and its
traditional ideas and/or skills are so useful for the field of current engineering
and sciences.
Why?
Because this phenomena is worst issue for structural design in
general.
In structural
engineering, however, the instability of a structure has an important problem
of compression buckling. Under a professor known for buckling theory research,
there was an opportunity in the cylindrical shell structure using Origami to study "the compression buckling
by which symmetry is broken." If it twists like a dust-cloth iris
diaphragm, pressing down the rolled paper fixed at both ends with both hands,
periodic wrinkles will appear suddenly in a certain critical point (since a
local periodic compression buckling pattern appears, this is a kind of the
multiplex bifurcation buckling phenomenon called "cellular buckling"). By the world of Origami, this wrinkles pattern is called a
Kresling-pattern", and is introduced by the French origami investigator's Kresling. As an experiment relevant to this,
there is a prominent compression buckling experiment of the cylinder shell
structure of YAMAKI.
However, the reason
revelation and symmetry of actions, such as the number of generating and its angle
of the wrinkles, and an angle variation, are torn needs to consider the
breakdown (two or more compression buckling modes should appear in a multiplex
singular points) of the energy equilibrium of bending moment and in-plane force
in the test specimen, and essentially becomes difficult. The author, I did
compression buckling research of this origami the analysis comparison model, applied
to the post-buckling theory of YAMAKI, and was fighting desperately every day
to that solution of a riddle through the geometric observation and reappearance
calculation of that way which are folded up.
An example of the folding
cylindrical structure principle using an origami
technique and symmetry-breaking phenomena
(at the Non-Linear Research Centre, University of Bath in the UK in Dr. Ariofs
overseas study, 2003); Academic Paper
``Twist buckling and the foldable cylinder: an exercise in origamih, Giles W.
Hunt, Ichiro Ario, Int. Journal of Non-Linear Mechanics, Vol 40, Issue 6, July
2005, Pages 833-843
Topic 2. Discovering/Creation from Structural Instability
One day, the professor Hunt called me, it left the important
portion of the Kresling pattern of Origami,
the truss was built, and there was a proposal that this would be applied to the
lightweight deployment structure. The fault which is regarded as whether does
it further clip to unstable phenomenon analysis and to carry out instability to
it and in which action and origami
carry out compression buckling is turned to its own advantage, the advantage of creating a light trussed
structure object foldable like compression buckling by little force is pulled
out, and it is said that it will use for the design of space deployment
structure. This was conversion of the way of thinking of like scales drop from
whose eyes, and when it cultivated the viewpoint for creating and carrying out
problem solving of a new innovation and engineering value, it became a turning
point of my research.
Homoclinic
bifurcation and chaos attractor in elastic two-bar truss,
International
Journal of Non-Linear Mechanics, Volume 39, Issue 4, June 2004, Pages 605-617
Multiple
duffing problem in a folding structure with hill-top bifurcation,
Chaos,
Solitons & Fractals, Volume 51, June 2013, Pages 52-63
Dynamic
folding analysis for multi-folding structures under impact loading,
Journal
of Sound and Vibration, Volume 308, Issues 3?5, 4 December 2007, Pages 591-598
Structural
stability of multi-folding structures with contact problem,
Journal
of Sound and Vibration, Volume 324, Issues 1?2, 10 July 2009, Pages 263-282
Topic 3. Weak point for recovery tools in Japan
At the time, it
flowed, the Chuetsu earthquake in the north of Tokyo occurred in October, 2004,
and we investigated the damaged structures by its disaster. It had become
impossible for the infrastructure to have damaged and used it in guerrilla at
the time of a disaster, and it was human-works for the restoration tool of how
it was made to restore quickly, and felt very scarce one. Moreover, the
restoration technique of the distressed area where in and outside the country is repeated, and
the necessity for a temporal bridge as a restoration means and a restoration
tool have been realized. The international joint research of the structural
instability problem of the buckling theory (including a singular point) of multiplex folding micro-structure theory
(MFM) accompanied by the multiplex singular point(s) of the chip box model of a
multi-stage pantograph mechanism was tackled with a professor of the Polish
science of academy (PAN).
Topic 4. Trigger of MB
development & Creation
of Deployable Bridge based on Origami
and Post-Buckling Theory
It
was passed several months after the earthquake. When I saw my kid who played by
a childfs toy,
in
my brain, it was made up by my knowledge of several hints in fundamental
engineering issues that deployable structure of the pantograph, how to recover
by a rapid restored way, folding patterns by origami idea, structural optimization,
post-buckling with singularity by computing, and related to engineering problem
and investigation on disaster zone to might be resolved it by origami ideas. I thought the
innovative possibility of the bridge and profitability might be born by the deployable
bridge to which "If a bridge could be folded simply whether
it couldn not be folded like folding paper, origami?", too. Or the idea that the
most suitable structural member is arranged and a bridge is developed by the
smallest power with "collapse of catastrophe" more natural than
energy minimum principle as an example. A bridge improves in a simple mechanism
in precast construction method, and when folding and needing in three
dimensions beforehand, it can be extended to choice completion which is not
seized with the form of the bridge of existence and is based on a principle of
energy-minimum like the buckling pattern of Origami,
and after that that maybe it should be made fixing and the structure which can
be reinforced, it flashed out.
The bridge combined by scissors structure is possible, but the accordion-like gate across which I often generally come by a construction site and a gate is lack of stiffness and easy for off-plate direction to make more unstable and when not controlling elasticity, it is not possible to keep equilibrium state with design mechanics. After extending during development to prudence, when not enduring a live load in addition to the prudence it is not useful as a bridge. Lightness of the part and the strength are also important, and a dynamics balance, structural stability and the most suitable structural form are needed, and I face choice of the expensive material of the specific tensile strength, a stiff balance and a compound optimization problem realistically.
But
a technical skill was requested of the way to make the thing which makes a
primary member convergent and the fail safe to secure the part strength and
reduce a part score multiple, making them ease stress concentration in the
environment bottom where high analysis and design are good at present-day
science but I thought it was not impossible by a specification. Or when
structure unstableness can be controlled well, it is the enlightenment to which
I say "They may be able to fold a
bridge efficiently."
But,
I had to understand the "Ori (it means FOLDing in Japanese word)"
structure which is an unsolved academic problem well for it. For example the
way to fold how to fold while keeping the strength as the bridge? The mechanics
about the collapse was undeveloped dynamics territory in spite of a specialty
of our country for a product of "Ori-Tatami (Multi-FOLDing)". Assistant
Prof. Taketoshi Nojima who was retired the department of physical mechanics
system in Kyoto University, mechanics researcher claimed "Origami engineering", I got the
chance when a study lectured on the solid folding pattern by Origami in JAXA, I had also
worked on a buckling analysis study of cylindrical shell of a Kresling-Ori by myself and had developed the
mathematical dynamics solution folded like a plane by the smallest energy then
at the time exactly. When it will be an efficient collapse in particular, I
have found out that I have a multiple singular point (A rip of symmetry and
multiple structural instability hide potentially.) mathematically. But for risk
to become one in case of heavy construction like the bridge structure highly,
that will be sensibly usually evaded, it is compound by use of structural
instability of pantograph mechanism and a fixed part of deck slab from
underhand idea, the whole system can be developed in multiple structural
stability (Multiple fail safe is established structurally.) by combining the
most suitable smart structural concept.
The
development structure is called ``Deployable
Structures" which there is a famous ``Rolling bridgeh in London and
often applied to folding mechanism of the space development structure in
English, but the development structure on the ground is influence of gravity in
fact, and its condition becomes general more severely than zero gravity space.
I thought you could not generally understand that I did not give the form to
that, and embodiment of an mechanics principle in the bridge was entrusted as a
prototype (fold and carry compactly, the specification which can be developed
rapidly) and the making was entrusted to a factory in a university for
experiments in the limited budget. The forming accuracy has also completed a
prototype in an early stage in less than 3 months thanks to a skillful
technical staff highly.
Topic 5. Comrade of MB development project
The plan of a temporary bridge
which can be folded with this mobility is proposed to the Japan Construction
Method and Machinery Research Insititute, and joint research has started to
take something used as a restored support structure at a disaster zone. First
it started from design model and materials processing test, and these
mechanical characteristic of a structure and feature were made clear through a
strong experiment at the various condition bottoms using a prototype version
with the length 6m for a person walking. I understood that it was unclear
gradually and was convinced of a possibility of the development to a bridge of
this structure by the folding mechanics such as the validity and the utility of
its function actually by making a prototype actually as big research results. What
are something useful for the time of an accident and something necessary? What
is the function of the bridge of necessity minimum as a true emergency
temporary bridge? What is made as a researcher of mechanics and/or dynamics? It
was not probable up to now or maybe that the break through might be made a
question of the dynamics no one considered as the bridge structure from applied
mechanics-like thought. A principle and a general-purpose structure of bridge
which is able to be installed development from an idea based on compression
buckling can also produce new directionality and uniqueness like technological
history and expect the synergistic effect as the construction technology of the
construction speed by a few people by such meaning.
Carrying MB0 for a footbridge by a trailer. The completed construction of MB0 in this campus
In
2010, I decided to consult with several engineering staffs of this university
and extend a prototype to 9m. On the maintenance this structure unit part
composition, and part replacement forms easily, it was made the excellent
structure. When it developed by technological application of a collapse,
something of 9m even became possible of 1m to fold, and the compactness cut
with portability by boat trailer was achieved.
Load
testing for design and development was put into effect by the prototype
specification of its latter period type, a result was concentrated and the consistency
was estimated right from various points of view. Technological development was
believed use of this first bridge as history of the bridge world and the
development was continued. I got the chance to put an opening to the public
construction experiment (walking through this bridge) experience into effect in
a river in a prefecture according to the event of a university (Refer Picture-1, 2 ). It was mainly to
experiment on opening to the public at this time, but if I failed, there was
also resolution which will evacuate development. Happily the first construction
experiment has also ended in the successful back as it was lined by load
testing.
These
study results which I presented our research at JAXA in Japan as the example of
the development structure with the expensive and inexpensive efficiency of the
structure. When showing the animation developing construction, a clamor and
many questions in detail were received. After that the pier special occupation
manufacturer which received an approval in bridge company and a pantograph maker
take part in joint research, and I have cooperation for an experimental
production and practical use of the actual size large at present (Refer Picture-3).
Picture-1
The development landscape of the prototype of the MB0 which is at the time of
television station coverage (at this campus of Hiroshima University in 2010)
Picture-2
The store state of the prototype MB0, colleagues and students
Topic 6. Prepare this rescue bridge for the next natural disaster
An
earthquake, a Tsunami and a typhoon (heavy rain) experience many natural
disasters, and our country will also hold something like fate to have to be
coexisting with rage of those accidents from now on. Need will be also
indispensable for building of the mobile area disasters prevention system which
is analyzing the accident situation of the past for it and is rescuing the
human life the intelligence of the modern technology science can help
aggressively from now on.
It's
repeated though we have learned a lesson to an accident (For example I prepare
with a lesson to a tidal wave of fire: Ansei first year (1854) Hiro-village of
a rice plant hill (present: Wakayama-prefecture Hirokawa-village).) in the
nature from the past and have given many suggestion, various, there is no end
to guerrilla-like natural disaster, and much noble life occurs at world all
part, and is taken away. Development contribution in detail of country
(disaster prevention foundation) making which is strong in necessity of
research and development and an accident of this field to defend national
assets and human life after accident occurrence so that it may be called
"when it's equipped and is here, without fear", even in addition to
utilizing a lesson of an accident, it'll be an important thing that the
development, the disaster prevention, the restored mood, the industrial
reinforcement and the area international contribution which connect with future
technology by new structure and concept are being maintained as a system by a
set.
It's
easy at a site as this match to put together, secure a lifeline at the time of
an accident and build a new restoration support system safely quickly and,
necessary. I'm thinking MB development for useful infrastructure restoration is
also one of important general-purpose quick restored tools technologically
socially to prepare for the next accident.
Picture-3 Aiming at practical use of the MB1.0 for first lightweight vehicles, during industry-academia common experimental production development
We realize that we should create a new type of bridge with speedy and automation of construction as a robotic of a bridge in close future. The use of a MB development project is spanned with quickly safely as the next role of "intermediary" is believed. Argument is deepened about a structure of the next generation by volunteers to prepare for the next disasters.
[Refer to]
A test
of the Mobile Bridge® Version 4.0 (MB4.0) over a real river demonstrated its
viability for practical use. During the test, the bridge was
set up without any foundation work, and a vehicle could easily travel across it. This was
achieved safely with very few people and without any problems. The MB4.0
viability test results were presented at a symposium of the Japan Society of
Civil Engineers (JSCE) on June 23, 2015, by Dr.
Ichiro Ario, Assistant Professor at the Institute of Engineering, Hiroshima
University.
*Please refer to our original publications for Origami and multi-folding mechanism like pantograph in the following;
[1]
Development of a prototype deployable bridge based on origami skill, Automation in Construction, Volume 32, July 2013, Pages 104-111,
Ichiro Ario, Masatoshi Nakazawa, Yoshikazu Tanaka, Izumi Tanikura, Syuichi Ono
< http://www.sciencedirect.com/science/article/pii/S0926580513000228>
[2]
Twist buckling and the foldable cylinder: an exercise in origami,
International Journal of Non-Linear Mechanics, Volume 40, Issue 6, July 2005, Pages 833-843, Giles W. Hunt and Ichiro Ario
< http://www.sciencedirect.com/science/article/pii/S0020746204001581>
[3]
Non-linear dynamic behaviour of multi-folding microstructure systems based on origami skill, International Journal of Non-Linear Mechanics, Volume 45, Issue 4, May 2010, Pages 337-347, Ichiro Ario and Masatoshi Nakazawa
< http://www.sciencedirect.com/science/article/pii/S0020746209002108>
[4]
Structural stability of multi-folding structures with contact problem, Journal of Sound and Vibration, Volume 324, Issues 1–2, 10 July 2009, Pages 263-282, Ichiro Ario and Andrew Watson
< http://www.sciencedirect.com/science/article/pii/S0022460X09001230>