morel: remotely launchable playthings to facilitate new ... · 3.1. multiple morels morels can...
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Morel: Remotely Launchable Playthings to Facilitate New Forms of Outdoor Play
Kenji IGUCHI
Keio University, Graduate School of Media and Governance,
Media Design Program
Abstract: This paper proposes Morel, physical plaything devices that facilitate the emergence of new forms of real-world outdoor play. Morels are ball-like objects with digitally enabled kinetic behaviors embedded within. They can detect the existence of other Morels in the vicinity, and can remotely make them launch up in the air. Morels encourage the improvisation of new games and play behavior, not by defining game rules on its own, but by adding behavioral possibilities to the environment while keeping the play rules open. Several games using Morels have been devised through playtesting. Through their characteristics, Morels allow players to explore a new realm of casual, flexible play. Keywords: Pervasive games, Mobile games, Physical play, Multiplayer, Ad-hoc rule improvisation, Casual Ludic activity
1. Introduction Research in digitally augmented reality-based
gaming has been on the rise for the past few
years. Most such attempts have taken the
approach of reaching out into the real while
having their feet set in the digital side.
The operational rules in these games are also
based on the kinds of play where the rules are
rather rigid, and do not intend to cover casual
play that is often practiced by children outdoors.
Such acts of play are full of improvised
on-the-spot rules and behaviors.
In this paper, we propose Morel, a physical
plaything device that supports and facilitates
the emergence of new forms of physical play. It
accomplishes this through a novel combination
of familiar physical properties and kinetic
actuation through wireless communications.
2. Motives Since entering the Keio University Inakage
Lab in 2002, I have been involved in several
digital entertainment projects [1][2][3] that aim
to bring computer-based content and the real
world together utilizing Mixed/Augmented
Reality (MR/AR) technology. They include Little
Red MR, a children's pop-up storybook in 3D,
and Veggie Diaries, a PDA game where the
player grew virtual plants on a real diary book.
Some of the elements those MR-based projects
had were the player's physical actions
influencing gameplay, and the adoption of
real-world elements as in-game objects. From
there, my interests extended into what is known
as pervasive gaming.
The goal of this project is to look at the field of
pervasive gaming from the “other side” and
reach out into the digital from the real, focusing
on children’s outdoor play as the basic medium
to use to accomplish that goal.
3. Overview Morels are cylindrical-shaped plaything
objects, approximately the size of soccer balls.
Their soft outer shells are made of urethane,
which allows them to be kicked and thrown like
ordinary balls. The cylindrical shape also allows
players to roll Morels on their sides.
Figure 1. A Pair of Morels.
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Morels operate in identical sets of two or more.
When a Morel senses the existence of another
Morel nearby, it will emit a sound to notify the
player. It will also make a sound when another
Morel has left the vicinity as well.
While other Morels are nearby, a player can
'charge them up' by holding and squeezing her
Morel. This will cause a tone, rising in pitch, to
be emitted from other Morels to show they are
being charged. When the 'charge' reaches its
maximum, the sound will change to a wailing
tone; if the charging player lets go and squeezes
once again on his Morel at this point, the
charged Morels will launch.
3.1. Multiple Morels Morels can operate with a minimum of two
devices in the area of play. However, when there
are three or more Morels in the area, play with
Morels can take on a much more unpredictable
style.
Squeezing one Morel will result in all other
Morels in the vicinity to react. A player can
launch multiple Morels simultaneously. A
launch of one Morel can also trigger chain
reactions, causing other Morels to launch one
after another continuously.
3.2. Activities Using Morels Beyond the above-mentioned characteristics,
there are no gameplay rules built into the
Morels themselves. Morels take a different
approach in design compared to existing
Pervasive Games. They introduce new behaviors
into physical play. However, Morels do not
dictate to players how to play. Much like a
wooden stick or a red rubber ball, players are
encouraged to play using Morels, instead of
playing them themselves. Players may play
games based on known rules, modify the known
games, or think up and improvise their own
ways to play.
Morels can be used for unstructured play such
as games of make-believe, or as devices to
augment existing games such as proximity
sensors to use in a game of hide-and-seek. And,
as has occurred during playtesting, they can
also be used for entirely new physical games in
which their unique functionalities become
integral aspects of gameplay.
Figure 2. Playing with Morels.
4. Related Works In this section, we will go over existing
products, pervasive gaming research projects,
playthings, and play theories having relation
with the concept of Morels.
4.1. Pervasive Games
4.1.1. Pac-Manhattan
Pac-Manhattan [4] is a pervasive game
conceived by the New York University's
Interactive Telecommunications graduate
program. The game is a recreation of the classic
dot-eating game Pac-Man using the streets of
Manhattan as the game field, with half of the
players residing in a control room and the other
half running in the city. Only the control room
players (“Generals”) have access to the view of
the entire map, and each street player is
connected to a corresponding General player by
a cell phone. Using the connection, street
players would act out their roles as Pac-Man
and the ghosts, each receiving advice from their
respective General players.
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Figure 3. Pac-Manhattan.
The technology of the game is kept primitive
on purpose: Wi-Fi and GPS technologies are too
unreliable to use as tracking and data uplink
methods, in an urban setting where players
were constantly running. The game was
successfully held on multiple occasions.
In Pac-Manhattan, computers map the street
players' locations for the generals on screens in
a control room. The computers also track scoring,
and keep the formula of the original game
intact: the more ghosts Pac-Man captured
during his powered-up state, the higher the
score for each individual ghost would be.
4.1.2. Can You See Me Now?
Can You See Me Now? [5] is a pervasive game
developed by media arts group Blast Theory and
the Mixed Reality Laboratory of the University
of Nottingham. The game is a physical/virtual
hybrid game of tag, where the chase takes place
both in a real world city and its digitally
reconstructed counterpart. Two groups of
players participate in the game: one physically
running in the real city, and the other running
in the virtual city using their computers. The
locations of the physical players are tracked
using GPS, and reflected on the virtual city.
In the game, players in the physical city run
after players in the virtual city. The players in
the physical city keep track of the locations of
the virtual players by using a Wi-Fi enabled
PDA. The game ends for the virtual player when
he is caught.
Figure 4. Can You See Me Now?
4.1.3. Seamful Game
Seamful Game [6] is a pervasive game
designed by Matthew Chalmers of the
University of Glasgow. It uses real world space,
GPS, and the spatial coverage (and lack thereof)
of Wi-Fi access points as crucial elements of
gameplay. While most games assume ubiquitous
wireless access and absolute game information,
Seamful Game is designed around the
unreliability of real world connections, and the
'seams' between zones of Wi-Fi coverage.
Players walk around in a designated game
area, trying to collect virtual coins that are
scattered around. The coins may be anywhere,
however players can only claim them for scores
while they are within the Wi-Fi coverage range.
If the player attempts to claim them from
outside the range, she will lose all of her coins.
The game requires players to understand the
areas in which Wi-Fi is and is not available in
the game area in order for them to win.
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Figure 5. Seamful Game.
4.1.4. Veggie Diaries
Veggie Diaries is a project we developed in
collaboration with Olympus Corporation in 2004.
In this game of virtual gardening, players plant
and grow animated vegetables on a physical
diary book by using a camera mounted PDA.
The game uses mixed reality technology to
superimpose a 3D image of the plant on top of
the diary book. Players are able to use several
real-world objects, not originally intended for
the game, as elements of gameplay.
The game, which consists of the diary book
and the PDA, is made so that it is “always on”
and can be carried around regularly, much like
Bandai Co. Ltd.’s Tamagotchi [7] virtual pet toy
series.
Upon beginning play, the player must first
find a soil bed to plant a seed. Paper pieces in
real space represent soil in the virtual space.
Players must obtain soil from pieces of paper, for
instance magazine cutouts. The player then
inserts them into the pages, using the pockets
attached to each page. The combination of colors
in the pieces of paper determines what the
planted seed will grow into. The seed can
become any of around a dozen possible
vegetables.
Players will need to periodically give water
and sun to their plants. Nutrients are hidden in
common road signs; Players capture them from
the signs using the camera mounted on the PDA.
To do this, players switch the system into
capture mode. When the player takes a picture
of a road sign, the system 'captures' the nutrient
trapped within the sign into the PDA. The
player then releases the captured nutrients by
aiming at their vegetables and pushing the
button again.
Over time, the plant would grow or wither
depending on how well the player cared for it.
Figure 6. Veggie Diaries.
4.1.5. OTOTONARI
OTOTONARI [8] is another one of our projects,
developed in collaboration with the Keio
University Murai Lab, and KDDI Inc. in 2005.
The game consists of a large number of players
(around 20-30) searching for and sharing
fragments of music by walking around in a
physical space and entering the vicinity of each
other.
Players carry a Wi-Fi enabled Windows
Mobile PDA, each starting off carrying a
different fragment of a somewhat complex
musical sequence. During play, they can
exchange copies of their fragments by moving
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into close proximity with each other. The goal
for each player is to collect as many fragments of
music as possible, in order to construct a rich
sequence the player can listen to at the end.
The rules of OTOTONARI are designed to
encourage players to move around a field,
mingling and cooperating with nearby players.
Figure 7. OTOTONARI Gameplay.
4.2. Playthings
4.2.1. Bilibo
Bilibo [9] is a toy designed by the Swiss
designer Alex Hochstrasser. It has the
characteristic of having no predefined way to
play. It is a colorful shell made of durable
polyethylene, with a wavy rim and two holes
opened near the edge. It contains no electronics
or machinery. How the user plays with Bilibo is
up to him or her, although its shape provides
affordances to many actions. Some actions
possible with Bilibo include spinning the shell
on its bottom, peeking through the holes, sitting
on it, donning it like a hat, scooping sand or
water with it, combining two Bilibos to form a
sphere, and so on.
Figure 8. Bilibo.
4.2.2. LEGO® blocks
The LEGO brand of toys [10] is a longstanding
line of plastic building block toys manufactured
by the Denmark toy manufacturer, The LEGO
Group.
LEGO sets generally come with instructions
to guide the user to build a certain LEGO
construction. The user is not limited to the plan
shown in the instructions, however, and is free
to combine bricks to build whatever they
imagine.
4.3. Theories
4.3.1. Huizinga’s Definitions
Play was first defined as a field of formal
study by Johann Huizinga in his book Homo
Ludens, [11] published in 1938. In the book,
Huizinga framed play as acts that stood on their
own, instead of as forms of practice or education
for the players to ready themselves for life.
Huizinga defined acts of play as acts that are
“executed in a limited frame of time and place,”
“arising from the player’s own intent,” “following
determined rules,” “having play itself as the
objective,” “not serious,” “accompanied by
tension and joy,” and “considered dissimilar
from ordinary life.”
4.3.2. Caillois’ Classifications
In his book Man, Play and Games, [12] Roger
Caillois classified play into four categories.
Agôn is a kind of play where the focus is on
competition, which includes games like Chess
and Baseball.
Alea is a kind of play that is based on chance
and probability, such as Poker.
Mimicry is based on behaving in accordance
to one’s imaginations, such as role-playing
games or make-believe play.
Il inx, which translates to “vertigo”, is play
that relies on physical sensations, such as
dancing or skiing.
In addition to these four classifications,
Caillois also provided a second criterion, an axis
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that began from LLudus, formally regulated play,
to PPaidia, improvisational free-form play.
4.3.3. Salen & Zimmerman’s classifications
Katie Salen and Eric Zimmerman, in their
book Rules of Play, [13] defines three categories
of play, each one a subcategory of the next.
Games are activities of play that play in
accordance to a formalized set of rules.
Ludic Activities are activities of play that
include games, but also include less formal
kinds of play where the rules are more vague
and often not codifiable, such as playing
make-believe, cops and robbers, or catch. Play as
defined by Caillois covers this category of
breadth.
Being Playful is the broadest of the three
categories, containing both the above two, but
also including playful states of minds in general,
such as accomplishing a non-play task in a
playful manner.
Salen and Zimmerman also discussed several
schemas to view games from, two of which are of
special mention here.
Emergence is a characteristic of systems in
which complex patterns emerge from a simple,
limited set of rules. While not really being a
game, one of the most famous examples of this
principle is John Conway’s cellular automaton
Game of Life, in which amazingly complex
behavior can be observed from a group of cells
that only follow three rules. Similar complexity
can emerge in interactive games as well, such as
the advanced techniques and maneuvers that
can be seen in simple games like Tetris or Go.
Transformative Play is a kind of play that,
in addition to being framed by its structure, can
modify the structure itself. This can apply to
various forms of play, such as rule changes in
the middle of a children’s game, user
modifications to a video game, and trends in
athlete behavior leading to a sports organization
updating the official rulebook.
5. The Device In this section, we will explore the specifics of
the Morels’ device design in further detail. We
will first discuss the backgrounds and the
problems that we intend to solve with Morels,
and then will explain the operational specifics of
the device implementation.
5.1. Background
5.1.1. The Sources of Regulations
One thing the definitions of play given by
Huizinga, Caillois, and Salen/Zimmerman all
agree on is that play comes into existence in the
presence of certain rigid structures, or
structures of regulation.
Lawrence Lessig, in his book Code, [14] cited
Architecture, Law, Norms and Markets as
regulators of human behavior upon discussing
digital rights and freedoms. In the current
context, Law and Architecture are particularly
significant: Law refers to rules set by humans
that discourages one from breaking them by
imposing penalties and other unfavorable
consequences, but can be broken if one is so
inclined. Architecture is the rules that manifest
themselves within the world itself and cannot be
broken, such as the laws of gravity or
thermodynamics.
While we are so used to the regulations of our
environment that we tend to forget their
existence, the environment (architecture) in
which an act of play takes place imposes a great
number of restrictions in shaping the rules (law)
of the game. We do not design physical games
where jumping ten stories high is a necessity;
nor do we design games where the game board
uses more than three dimensional axes. The
architecture of the environment and our bodies
prohibits such game rules from being playable.
The rise of computers and digitally created
virtual worlds now allow designers to instate
regulations much more freely than in the real
world. The designer is handed the task of
constructing the architecture of the game world
as much as the operational game rules
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themselves. Gravity can be as weak as that of
the moon, and objects can both pop out of and
disappear into thin air. Rules set by digital code
can also be enforced much more strictly than
non-digital rules, as all rules set by code are
unbreakable rules of architecture by default.
We can classify the restrictions that regulate
what we can and cannot do during play into a
two-dimensional matrix. The vertical axis
represents the level and degree of regulation,
with the elements below regulating the above.
The horizontal axis represents the realm (real or
digital) from which the regulations originate.
Player Actions Action
Rules (Law)
Real World Environment
Environment
(Architecture)
Real Digital
Figure 9. Classification Diagram for the Regulations of Play.
In the chart, Player Actions and Real World
Environment span across both the real and
digital realms, since even computers themselves
exist as machines made out of physical objects in
the real world environment. Hence, player
interaction with machines can only occur in the
real world. [15]
We will now examine the different kinds of
play using this diagram.
5.1.1.1. Sports / Physical Games
Real-world Sports and Physical Games such
as board or card games are different kinds of
play, but they share a common trait in that the
game rules are never more than agreements
made between players, and they are only
enforced at the real world level. While some
technology may be used to allow finer precision
in the application of the rules, e.g. stopwatches
or high-speed cameras, the final judgments are
done by human arbiters.
Player Actions Action
Agreements Rules (Law)
Real World Environment
Environment
(Architecture)
Real Digital
Figure 10. Diagram for Sports / Physical Games.
While transformative “house rules” can be
created for local play sessions, the rules for
sports and board games are usually kept rather
tightly. They are often codified in an official
document, managed by entities such as player
associations or game publishers. Changes to the
official rules occur rarely, and when they do
happen, they are regarded as major events
among player communities.
5.1.1.2. Computer Games
In computer games, almost all of the
regulations, be it based on the environment or
the operational game rules, are defined through
digital code. While digital code itself is indeed
restricted by the real world environment and
the computing hardware it runs on, the power
granted to the designer is much stronger than
those of traditional games.
Player Actions Action
Rules (Law)
Digital Code
Real World Environment
Environment
(Architecture)
Real Digital
Figure 11. Diagram for Computer Games.
On the other hand, from the viewpoint of
transformative play, this can be a downside.
Since digital code regulates both the operational
rules and the characteristics of the environment,
they are enforced in the same rigid manners as
the environment (architecture) of the world.
Deviations from the rules can only be done as
much as the designer of the game allowed them
to be possible. Although some computer games
such as Valve Corporation’s Half-Life 2 [16] or
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Linden Lab’s Second Life [17] have been built
with an open-ended structure to encourage the
development of modifications and user-created
content, many games are still closed boxes, only
allowing minimal amounts of transformative
play.
5.1.1.3. Pervasive Games / Pervasive Sports
Player Actions Action
Agreements Rules (Law)
Digital Code
Real World Environment
Environment
(Architecture)
Real Digital
Figure 12. Diagram for Pervasive Games / Pervasive Sports.
Pervasive games bring parts of the regulating
powers granted by digital code to physical
games. This allows physical games to utilize
rules that used to be practical only to computer
games, allowing the designer to offload complex
calculation and memorization tasks (scoring and
storytelling, for instance) to computers. [18]
Like computer games, the digital element of
pervasive games and sports also brings its
regulative rigidness along. Again, this can be
seen as both a blessing and a curse. From one
point of view, it can free the players from having
to understand and follow potentially complex
rulesets. However, it also limits casual deviation
and experimentation with the rules of the game,
at least for the parts that are enforced by the
computer.
5.1.1.4. Physical Informal Ludic Activities
Physical informal ludic activities are the kinds
of play that can be exemplified by casual
children’s games such as Tag, Hide and Seek,
Kick the Can and Make-Believe Play. They
differ from formal games in that the agreements
between players are much more relaxed, vague
and malleable. We have divided the
environment and rule layers in the diagram to
make this distinction more clear.
Player Actions Action
Informal,
Amorphous
Agreements
Rules (Law)
Real World Environment
Environment
(Architecture)
Real Digital
Figure 13. Diagram for Physical Informal Ludic Activities.
During informal ludic activities, kids often
propose a time-out to recommend a change to
the rules, whether it may be to increase the
number of the people who are "it", or to prolong
the time a person who was shot stays "dead."
(Outrageous proposals are rejected by other
participants, obviously.) This can happen
between rounds or, occasionally, even during the
game, merely because "It's more fun that way."
This is obviously out of the question in a formal
game of sports. Such changes can only work out
because of the implicit understanding between
participants that the goal of their activities is
having fun, rather than outrunning the
opponents and winning the competition.
Some informal ludic activities may not even
have coherently organized sets of rules. In the
case of make-believe play, the only bind on
player behavior is the principle of acting out
their roles.
5.1.1.5. Pervasive Informal Ludic Activities
The activities mentioned in the previous
section have so far been confined to physical
play. Little attempts have been made so far to
mingle them with digital technology, as has
been explored with pervasive games and sports.
It should be noted that simply trying to carry
over the digital code of such games to coexist
with the amorphous and whimsical agreements
of informal ludic activities do not work. This is
because the digital code in those games does not
make distinctions between regulative elements
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that reside in the operational rules, and those
that do in the play environment.
As digital code governs its regulations in a
strict, forceful manner, the act of regulating
operational rules through code conflicts with the
relaxed nature of the agreements of informal
ludic activities.
Therefore, in order to introduce and utilize
digital code into this field of play, it is necessary
to make clear distinctions with the regulations
at design time. Regulations that can be
interpreted by the player as an extension of the
behavior of the real world environment may be
featured. However, regulations that can be seen
as operational rules for a specific game should
be avoided, or at least kept to a minimum.
In the diagram below, the box representing
Digital Code has been reduced in size, to act
only as extensions of the real world environment.
It makes room for the Informal, Amorphous
Agreements to cover over both the Real and the
Digital fields.
Player Actions Action
Informal, Amorphous
Agreements
Rules (Law)
Digital Code
Real World Environment
Environment
(Architecture)
Real Digital
Figure 14. Diagram for Pervasive Informal Ludic Activities.
It is this little-explored category of play that
we intend to target with Morel. They are neither
games nor play; instead, they are devices to
facilitate and enable new acts of play.
5.1.2. Rule Design Patterns
Game rules for both sports and video games
can be said to exist through a combination of
rule design patterns – snippets of rules that, by
themselves, do not make a game, but can be
combined together to form a functioning game.
Some patterns can become popular and find
themselves reused for different games. The
concept of balls as key gameplay tokens, for
instance, has proven to be very popular in
physical games and sports.
Many patterns rely on the regulations of the
environment in which they operate. Balls can
only work due to the Earth's gravity and
abundance of flat surfaces, and the rule pattern
"You cannot touch the ball with your hands"
works out only because humans possess varying
amounts of dexterity in their hands and feet.
The same can be said for rule design patterns in
video games as well. For instance, the concept of
charging owes a lot to the behavior of
pushbuttons, which maintains a particular state
while depressed.
It is possible to duplicate the rule design
patterns of physical play activities by
simulating the real world environment in digital
code, to the extent it is possible. On the other
hand, bringing patterns of computer games into
physical play is harder and often more costly,
since less freedom is granted to the designer in
the real world in regard to manipulating the
environment.
5.1.2.1. Rule Design Patterns in Morels
Pervasive Play provides an opportunity to
bring design patterns formerly confined to
computer games into physical play. Morels
implement a number of common rule design
patterns seen in computer games, but we
selected patterns with origins in real world
phenomena. This was done to make the
“porting” easy and to keep the technical
complexity to a minimum.
Charging, or keeping a button held down to
accumulate energy, has been used in various
video games. One early example of note is
R-TYPE, [19] a shoot-em-up game by Irem inc,
where the player's spaceship had the ability to
boost the power of its laser by holding the fire
button down until the on-screen charge meter
became full. Charging tempts the player with
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strong attack at the cost of a temporary state of
vulnerability.
Radars, or the ability to detect nearby
entities that may not be necessarily visible from
line of sight, have increased in popularity since
the introduction of 3D graphics. Notable games
which feature them include Defender [20] by
Williams, the first game to feature a view of
off-screen objects, and the Metal Gear Solid [21]
stealth action game series by Konami Inc, as
well as many games in the flight simulation and
real-time strategy genres.
Chain Reactions, or one action by the
player becoming the catalyst to a series of
further happenings, can be seen in the
Bomberman [22] action game series by Hudson
inc., or the falling blocks game Puyo Puyo [23]
by Compile inc. and later Sega inc. (Known in
western markets as Puyo Pop.) Both games
differentiated themselves from other similar
games by emphasizing the excitement of
head-to-head battles, where both players aim to
build large chains, setting off huge attacks
against their opponent.
Power proportional to Distance, or
attacks dealing more damage when the player is
in close proximity to the target, has been
implemented in various shoot-em-up games. The
element invites players to take risks in return
for greater damage.
5.1.3. Miscellaneous Notes
In addition to the aforementioned traits of
Pervasive Informal Ludic Activities and Digital
Rule Design Patterns, we focused on the
following aspects in the design of Morel.
Playable Anywhere. A common problem
with pervasive games is that they cannot be
played in random locations without advance
arrangements, due to their steep requirements
of data about the play area and/or special
hardware equipments. We aimed to minimize
this problem in designing Morel. By making
them portable, and having them communicate
with other units of the same type, we were able
to avoid making assumptions and increased
reliance on the environment.
Physical First. It follows from the above
focus of being able to play anywhere that Morels
would be played outside in open spaces. We took
care in having the device accommodate large
kinetic actions by the player, such as throwing
or kicking.
The core behavior of Morels were determined
by first designing a hypothetical prototype game
(explained in section 6.1.1,) designing a device
for use with that game, then generalizing its
features to encourage transformative play and
emergent behavior.
5.2. Implementation
5.2.1. Mechanics
The functions of Morel are embedded within
the Morel Core, a small box located in the center
of Morel's soft outer shell. It contains an acrylic
tube with a short spring-loaded wooden rod
inside, locked into place by a metallic lever. The
lever is connected by wire to a motor, which can
roll the wire up to pull the lever. When the lever
is sufficiently pulled, it lets go of the
spring-loaded rod, letting the rod launch out of
the casing. The launching mechanism takes
inspiration from the mechanism used Kurohige
Kiki Ippatsu, [24] a classic party game common
in Japan released from Tomy, Co. Ltd. in 1975.
Figure 15. The Morel Core, Closed.
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Figure 16. The Morel Core, Opened.
The lid of the core is kept slightly open with a
smaller set of springs. The lid closes only when
the Morel is squeezed. Closing the lid will
trigger a built-in switch, notifying the module to
send a query signal instead of a vicinity signal.
Spring
Rod
Acrylic Tube
Release Lever
Microcontroller,
Wireless moduleBatteries
Outer Shell(Urethane)
Motor
gearbox
Figure 17. Morel Core and Shell Diagram.
To prevent the core casing from slipping out of
the outer shell, a band of rubber is wrapped
around the Morel’s shell. The band is attached
to the bottom of the core case, and has a hole
punched open so that the wooden rod can extend
through. The band also serves as a flexible
handle for the player to hold the Morel.
5.2.2. Electronics
In the current iteration, the motor, wireless
communications and several other devices are
controlled through the PROTO1BOARD, a
circuit board that contains an AVR
ATmega128L microcontroller and a CC2420
ZigBee wireless communications chip with an
embedded antenna. The program is written in C.
The Morel program utilizes the MOXA library, a
software library that provides simplified access
to specific features on the PROTO1BOARD such
as serial and wireless communications.
Figure 18. The PROTO1BOARD.
In addition to the PROTO1BOARD, the Morel
core also houses a secondary circuit board to
augment features that the PROTO1BOARD
does not provide. This board contains a
TA7267P motor driver IC, a 7806 regulator IC
and a set of I/O connections to other devices
contained within the core, such as the power
switch, battery, motor, and speaker. The circuit
and the motor are powered by a single 9V 006P
battery.
5.3. Behavior Morels operate in five modes: Out of range,
Within range, Charging, Fully charged, and
Launching. We will cover each of the modes in
detail.
Figure 19. Behavioral Diagram of a Morel’s
Internal Modes.
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5.3.1. Out of range
When first turned on, the Morel enters the
Out of range mode. In this mode, the Morel
constantly emits "vicinity" radio signals to find
other Morels in its vicinity. When the Morel
receives such a signal from another Morel, it
returns an "acknowledgment" message, and
upon receiving the acknowledge signal the
Morel switches into Within range mode.
If the Morel is squeezed in order to charge
other Morels during this mode, it will emit a
short "error" sound to remind the player that no
Morel nearby can be found. If it is squeezed in
any other mode, it will either send a “query”
signal (or a “launch” signal, if there is a fully
charged Morel nearby) to all other Morels in the
vicinity.
5.3.2. Within range
When the Morel is receiving a “vicinity” signal
from another Morel, but nothing beyond that is
happening, the Morel stays in this mode. It will
stay in this mode as long as it keeps receiving
"acknowledgment" signals in response to its
"vicinity" signals. If it fails to receive the
"acknowledge" signal for a set number of times,
it will fall back to Out of range mode; on the
other hand, if it receives a "query" signal from a
nearby squeezed Morel, it will switch to
Charging mode.
The Morel will emit a short distinguishable
melody every time it switches into the Within
range mode, or drops back to Out of range mode.
These sounds can be used by the player to figure
out the radio range of the Morel, which is
otherwise not perceivable.
5.3.3. Charging
When the Morel is receiving a “query” signal
from another Morel, the Morel enters Charging
mode. For each query signal received, the Morel
increments its internal charge value variable by
a set amount. The amount is proportional to the
radio strength of the received signal. Therefore,
the closer the sending Morel, and stronger the
signal is, the faster the receiving Morel charges.
The processing of query signals stack up, so
having two Morels nearby both sending query
signals will result in a faster charge.
During this mode, the Morel will emit a
continuous noise that rises in pitch as its charge
value rises. Players can have a grasp of the
current charge level and speed by listening to
the pitch of the sound and the rate in which its
pitch rises.
5.3.4. Fully Charged
When the charge value variable of the Morel
exceeds a set amount, it enters Fully Charged
mode. The sound will change to a repeating
wailing siren tone, which can be clearly
discerned from the charging noise. The tone
repeats until the Morel either leaves the radio
range of other Morels, or is launched.
5.3.5. Launching
Finally, when the Morel in the Fully Charged
mode receives a launch signal, it will enter
Launching mode and will immediately start the
launch sequence. The sound changes to a single
high-pitched tone, and the internal motor is
activated to set off the spring-loaded rod. The
actual launch occurs several seconds after the
high-pitched tone starts to play. The tone serves
as a warning for the player to remove her face or
other vulnerable body parts away from the
“muzzle.”
6. Evaluation and Play In the following section, we will discuss the
methods of evaluation we used in the
development of Morel, and the feedback results
of each evaluation. The results range from
questionnaire feedback to the emergence of new
game rules for use with Morels.
6.1. Test 1: Flash Prototype On December 20, 2005, before we developed
the actual Morel hardware devices, we carried
out a preliminary playtest of its concepts using a
mock-up implementation of Morel’s behavior.
The mock-up was built with a laptop computer
running an application built in Flash, and a
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Bluetooth wireless mouse. The mock-up
application implemented the basic behavior of
Morel by playing sounds when it detected mouse
movement, which consequently was when the
wireless mouse was within the laptop’s radio
range. It began charging and making sounds
when the mouse button is held down, and
displayed a large “Popped!” message onscreen
when the mouse button was let go after the
program reached full charge.
The behavior of launching differed slightly
from the current revision in this first prototype.
Figure 20. Prototype Flash Application.
The playtest was carried out by having
players place the laptop on the ground, and
moving around in real space while holding the
wireless mouse. The laptop served as the
placeholder for the receiver Morel, while the
wireless mouse was for the sender Morel. While
this setup did not allow mutual launches or
kinetic actuation, it successfully served as a
rough approximation of the actual hardware
that was yet to be built at the time.
In the playtest, participants played a game
named Cops & Bomber, a game we designed to
play using Morels.
6.1.1. The Prototype Game: Cops & Bomber
Cops & Bomber (originally dubbed Infiltrator)
is the “default” game that we designed the
functions of Morel for players to use. It combines
elements from outdoor games such as Kick the
Can or Cops & Robbers with Morel's
functionality of range detection and remote
launching.
Figure 21. Morel Prototype Cops & Bomber
Playtest.
6.1.1.1. Basic Rules
Players divide into two sides. The cops side
holds many players, while the bomber side
consists of a single player. Each side owns a
single Morel. The bomber carries his Morel with
him, and the Cops team keeps their Morel in a
fixed, stationary location.
The bomber’s objective is to get within the
radio range of the cops’ Morel and launch it. The
cops’ objective is to prevent this by physically
tagging the bomber. The twist is the additional
rule that states where the players can tag or be
tagged. The bomber can only be tagged by the
cops while he is inside the radio vicinity of the
cops’ Morel, while the bomber can tag the cops
while he is out of the cop Morel’s range. The
game ends if the bomber successfully launches
the cops’ Morel, the bomber is captured, or the
bomber tags all the cop players.
6.1.1.2. Dilemmas
The bomber has an incentive to approach the
cops’ Morel, however he also bears the risk of
capture if he does so in a blatant manner. The
cops, while having strength in numbers, are
vulnerable in all but one location in the play
field (the vicinity of the cops’ Morel.) Players in
both teams must be aware of which area they
are currently in, and take mental notes of the
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signal strengths of the cops’ Morel to figure out
their “safe zones” or “danger zones.”
6.1.1.3. Strategy
At the beginning of the game, the cops can
either elect to place their Morel in a hidden
location where the bomber will have a hard time
finding, or in an obviously clear place, which will
act as a bait to lure the bomber into open space.
The bomber has two strategic options as well.
He can either take the stealth approach, trying
to launch the cops’ Morel from an undetected
but within-range location, or take a blitz
approach and quickly launch the Morel before
the cops can react.
6.1.2. Findings
Contrary to expectations before the playtest
that players would engage in stealth tactics,
players tended to frequently confront each other
and teeter at the invisible edge of the radio
range, where the roles of the capturer and the
captured were to be reversed. After some time of
facing off each other, one side would break the
equilibrium by making a dash, which the other
team then followed. We learned that some
additional rules may be required to balance the
game some more, as the game in its current
state allows for the cop players to form a human
wall around their Morel and bring the game to a
stalemate.
Aside from the Cops & Bomber game, it was
interesting to see that emergent behavior could
already be observed at this early stage. Between
games, players were passing the wireless mouse
around each other while keeping the mouse
button held, to see who would end up holding
the mouse when the charge went full.
We received a suggestion from one of the test
participants to require an additional click before
the launch would occur. Through consideration,
we decided that this model would contain better
potential in the improvisation of rules. By
separating the charging with the launch signal,
it becomes possible to charge a Morel first and
then carry it to another location while it is still
fully charged, but not yet launching. This
behavior was later built into the hardware
version of Morel. It allowed games like
Quickdraw and Fugitives, which we will explain
in sections 6.2.1 and 6.3.1 respectively, to
develop.
6.1.2.1. The “Sense of Radio”
We have found that after being exposed to
Morel and playing for a while, players develop
what can be described as a virtual “sixth sense”
which piggybacks on the sense of sound, that is,
the sense of radio.
The connection between radio and aural cues
that Morels make seems arbitrary and random
at first, but as the player learns the relation
between the sounds and the radio situation of
the Morels, the sounds eventually become
second nature as to what is currently
happening.
6.2. Test 2: Two players We held the first playtest with actual Morel
hardware on October 17, 2006. There were five
participants, however due to time constraints
only two were present together at a time.
Participants had advance knowledge of the basic
behavior of Morels. We handed the Morels to
them, and observed the actions they took.
At the time of this playtest, Morels charged at
a fixed speed, regardless of the signal strength
of the squeezed Morel’s query messages.
Through this playtest, a group of participants
came up with a simple two-player game called
Quickdraw.
6.2.1. Developed Game: Quickdraw
Quickdraw is a game for two players using
two Morels. It is a variant of the game of
Chicken, with an additional twist at the end.
6.2.1.1. Basic Rules
Two players each hold their own Morels. On
the calling of the start of the game, both players
immediately squeeze on their Morel, trying to
charge up and launch each other's Morel first.
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Eventually, one will reach full charge status
faster than the other, and will begin the launch
sequence once it is triggered. When this happens,
the player carrying the soon-to-launch Morel
attempts to pin her Morel against the other
player, while the other player tries to run from
it.
The game ends when the Morel goes off and
releases its spring-loaded rod. The player with
the launched Morel wins if she manages to have
her Morel pushed against the other player in the
moment it went off, poking him with the rod.
The other player wins if he successfully evades
the launching player and the rod hits nothing
but air.
Figure 22. Quickdraw Gameplay.
6.2.1.2. Dilemmas
Both players need to be aware of the states of
both Morels, which can be hard since both are
close together and making sounds at the same
time. When a Morel reaches full charge state,
the players must immediately recognize which
is the one that did, whether it is the opponent’s
or not, and start the squeeze/escape or pursuit
accordingly, all in a split second.
6.2.1.3. Strategy
For the escaping player, it can be
advantageous to start running first and squeeze
afterwards instead of the other way around.
This way, she can get a head start in her escape
if the chasing player was waiting for the launch
sound as his cue to decide his actions.
6.2.2. Findings
With the actual hardware in play, the largest
difference from the previous test was the fact
that both of the two Morels could be picked up,
moved, charged and launched, instead of being
one-way. We frequently observed scenes where
participants were running after one another,
both persons carrying Morels, and with one
trying to launch the other.
During the playtest, there were times when
the Morel Core slipped out of the soft outer shell.
We also received feedback from a participant
saying that he could not hear the target Morel’s
charging sound when he was standing far from
it but still within its range.
Drawing upon the feedback and the game
structure of Quickdraw, we subsequently made
the following modifications to the behavior of
Morels:
• We made the squeezed Morels
themselves to make sounds in addition to
the nearby charging Morels. This sound
was made to be distinguishable from the
charging sound.
• We changed the charging speed to be
inversely proportional to the signal
strength of the squeezed Morel.
• We added a rubber belt to the Morel Core
encircling the soft outer shell, to prevent
people from inadvertently having the
Morel Core drop out.
6.3. Test 3: Four players We held a playtest with four participants and
two Morels in November 9, 2006. Participants
had advance knowledge of the basic behavior of
Morels. We handed the Morels to them, and
observed the actions they took. A team-based
game called Fugitives emerged out of the test.
6.3.1. Developed Game: Fugitives
Fugitives is a game for two teams of players
using two Morels. Its rules are more complicated
than that of the two-player Quickdraw, with
elements of ball-based sports and chasing games
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both existing within the rules. The rules share
some commonalities with the earlier Cops &
Bomber, however in Fugitives the game is a
conflict of many versus many. A notable
characteristic that the game shares with Cops &
Bomber is that the two teams have different
goals, making the conflict asymmetric.
Figure 23. Fugitives Gameplay.
6.3.1.1. Basic Rules
Players divide into two teams, the fugitives
and the pursuers. Each team carries a single
Morel. The carriers of the Morels are not fixed.
The fugitives team tries to avoid having their
Morel carrier ("fugitive carrier") physically
tagged, while trying to charge and launch the
pursuer team's Morel. The pursuer team tries to
have their Morel carrier ("pursuer carrier") tag
the fugitive carrier, while trying to avoid having
their Morel charged up and launched. The game
ends when either team's objective has been met.
6.3.1.2. Dilemmas
The fugitive carrier has an incentive to avoid
being close to the purser carrier, since her team
will lose if she is tagged by the pursuer carrier.
However, going too far away from the pursuer
carrier has negative effects as well. While doing
so will keep the fugitive carrier safe from defeat,
it will also deny her victory, since the fugitive
team's goal is to launch the pursuer Morel –
which is not possible if the fugitive carrier
moves out of the pursuer Morel's radio range.
The pursuer carrier, on the other hand, has an
incentive to approach the fugitive carrier, since
his goal is to physically tag her. This has to be
done swiftly though, as the closer the pursuer
carrier gets to the fugitive Morel, the faster the
rate of charging becomes.
6.3.1.3. Strategy
Passing plays an important role in Fugitives,
both for the fugitive and pursuer teams. Since
defeat for the fugitive team happens only if the
person who got tagged was carrying the Morel at
the time, the fugitive carrier can avoid losing by
throwing his/her Morel to another team member
and becoming a non-carrier. This can only be
used for defense, though, as the Morel cannot be
kept squeezed while being thrown.
For the pursuer team, an important strategy
is resetting the Morel's charge to zero to avoid
launch. A Morel resets its charge value
whenever it goes out of the ranges of others.
Temporarily throwing the pursuer Morel to a
team member out of range, and immediately
having it thrown back, becomes a vital move.
6.3.2. Findings
Fugitives was a Morel game with by far the
most depth and strategic possibilities. We
recognized that an increase in the number of
players could boost the complexity of gameplay
significantly. Passing Morels between players,
in particular, added a new dimension to the
gameplay.
On the other hand, participants also noted
what may happen if all players carried Morels of
their own. The situation would enable
large-scale free-for-all style games in addition to
the current team-based ones. The possibility of
such games remains to be explored.
Again drawing from the feedback, we built two
additional Morel devices after the test. The total
number was brought up to four.
6.4. Test 4: Many Children On January 6 and 7, 2007, we carried out a
test to evaluate various children’s reactions to
Morels, at the Shonandai Culture Center
Children’s Museum. We used four Morels for
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this test, all out in the play area at the same
time.
Figure 24. Instructional Panel Used at
January 2007 Playtest.
At this test, in addition to observing the
participants’ behaviors, we also requested
participants to fill in a questionnaire form. The
criteria for the form are as follows:
• Entertainment. Were the acts of play
using Morels fun and entertaining?
• Creativity. Did playing with Morels
inspire the participant to make use of
them in new ways? Does it have the
potential to be used in new ways?
• Cooperation. Did playing with Morels
with multiple people cause the
participant to notice things that she
would not have otherwise?
• Operation. Were Morels were easy to
use?
• Reliabilit y. Did the Morels work
reliably?
• Overall. How satisfied was the
participant overall?
We designed the questionnaire sheet with
icons, drawing upon the design used in Yutaro
Ohashi’s research in interactive learning toys,
[25] so that participants of varying age and
literacy shall be able to comprehend the
questions being asked. The answer fields used
icons of faces instead of words or numbers, in
order to reduce the possibility of error for young
children.
Figure 25. Questionnaire Sheet.
6.4.1. Participants
Due to time constraints and safety concerns,
the test was held inside the Children’s Museum
building. The evaluations were made mainly by
children visiting the children’s museum. The
playtest booth was located near the museum
lobby, where visitors usually gathered to rest or
have lunch breaks. Participants who caught
notice of Morels in the area were invited to play
with them, and fill in a questionnaire form
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afterwards. The time of experiencing Morels for
each participant ranged from 10 to 30 minutes.
Across the two-day course of the playtest, we
were able to obtain questionnaire feedback from
35 individuals in total.
The details of the participants’ demographics
are as follows:
Figure 26. Participant Gender Graph.
Gender Samples
(Percentage)
Male 15 (42.8%)
Female 20 (57.1%)
Total 35 (100%)
Figure 27. Participant Gender Table.
Figure 28. Participant Age Graph.
Age Samples
(Percentage)
3 1 (2.9%)
4 3 (8.6%)
5 1 (2.9%)
6 9 (25.7%)
7 8 (22.9%)
8 5 (14.3%)
9 3 (8.6%)
10 4 (11.4%)
11 1 (2.9%)
Total 35 (100%)
Figure 29. Participant Age Table.
6.4.2. Observed Behavior
Figure 30. Playtesting by Children.
Development of organized rules were not
observed, presumably mainly due to the nature
of the playtest in that only a few participants
were present at any given time. However,
participants adapted quickly to Morels’
behaviors once they were shown what the
devices did.
Emergent Behavior: After comprehending
the behavior of Morels, children initially played
by picking up a Morel and trying to launch the
others with it. When multiple children were
handling multiple Morels, however, some of
them could be seen exhibiting behavior not seen
alone:
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• Getting surprised when the Morel they
are holding begins to charge, when they
thought they were the ones who were
sending the charge
• Moving their heads close to individual
Morels to discern which Morel the sound
they are hearing is coming from
Transformative Play: Several ways of
using Morels emerged during playtesting, some
that we anticipated in advance and some that
we did not. The former occurred when a child
placed a Morel on the ground upside down, then
attempted to stack another Morel on top of it,
right side up.
The latter occurred when a pair of children, a
brother and a sister, began holding Morels in a
horizontal manner by using the stabilizing belt
as a handle. They were pretending to use them
like a gun, having the other child charge and
launch them.
Figure 31. Shotgun Make-Believe Play.
6.4.3. Questionnaire Results
The questionnaire received generally good
feedback in entertainment value, ease of
operation, reliability and overall satisfaction.
Negative feedbacks were seen in the creativity
and cooperation criteria, however. This partly
owes to the large number of individuals who
visited the museum without their friends, and
experienced Morel alone. Participants who
answered negatively for creativity (creative
usage potential) also had generally answered
the questionnaire after a relatively short time
with the device; Most participants who played
longer, generally more than 10 minutes, began
developing at least one way to use Morels.
Figure 32. Questionnaire Evaluation
Results.
Some comments include:
• “I couldn’t figure out how they worked,
but it was fun.” (7 years old, male)
• “I wanted to play by putting it in front of
a door.” (6 years old, male)
• “Playing with wireless communications
was fun. It was very curious. I want to do
it again.” (8 years old, female)
• “It was like a robot, very fun.” (10 years
old, female)
• “The ‘beep’ sound and the jumping were
fun.” (8 years old, male)
• “I want them to have faces. It would be
nice if the sounds they made were
talking voices.” (11 years old, female)
We were able to find indications of enjoyment
in virtually every comment made by
participants.
6.4.3.1. Questionnaire Analysis
In writing the questionnaire questions, we
had a hypothesis regarding the general
tendency of participants: “Morels are social by
design, due to its characteristic of requiring
more than one entity to function at all.
Therefore, overall satisfaction should be reliant
on the number of players involved in the play.”
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We performed a regression analysis between
the questionnaire answers for the Cooperation
and Overall Satisfaction factors.
Regression Statistics
Multiple R 0.623956303
R2 0.389321468
Adjusted R2 0.370816058
Standard Error 0.553769881
Observations 35
ANOVA
df SS MS F Significance F
Regression 1 6.4516 6.4516 21.0383 6.2002E-05
Residual 33 10.1198 0.3067
Total 34 16.5714
Coefficients
Coefficients
Standard
Error t Stat
Intercept 3.6037 0.2308 15.6127
Cooperation 0.3226 0.0703 4.5867
P-value Lower 95% Upper 95%
Intercept 8.43725E-17 3.1341 4.0733
Cooperation 6.2002E-05 0.1795 0.4657
Figure 33. Regression Analysis for Cooperation and Overall Satisfaction.
Through the analysis, we found a moderate fit
of 0.39 for R2. We then attempted to reject the
null hypothesis at a significance level of 1%. We
learned that the P-value is less than 0.01, and
the t stat for Cooperation is 4.5867, larger than
the t boundary of 2.733 at with 1% significance.
The null hypothesis could therefore be rejected.
We were able to confirm that Cooperation
affected Overall Satisfaction.
7. Conclusion and Future Work 7.1. Future Work
7.1.1. Hardware
In the future, we will develop a new version of
the Morel hardware to address limitations
existing in the current revision. Some of the
targets include a better aesthetic appearance for
the shell, a smaller form factor for the core,
better reliability by simplifying the internal
structure, and allowing the core to operate on a
set of standard AA batteries instead of the
current setup with the less common 9V battery.
7.1.2. Software
The software is currently written in C,
specifically for the AVR microcontroller. We will
port the code over to the Talktic virtual machine
programming environment, [26] developed by
Yoshimasa Niwa of Keio University. We expect
moving to Talktic, which is based on
ECMAScript, will make the code more easily
portable to other hardware platforms. Another
possibility we are looking into is a web-based
online Flash demonstration of Morel, reusing
ECMAScript code from the Talktic version.
7.1.3. Gameplay
We wish to hold playtests in higher numbers
and frequencies, in order to obtain more
information on player behavior and how they
will play with Morels, along with rulesets for
more new games. In particular, we still lack
observational information on the behavior of
children in situations of play with
non-fluctuating members, longer durations, and
outdoor environments.
The eventual goal is to compile a book of game
rules and play ideas to distribute along with the
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Morels themselves. Much like the instructions
that come with a LEGO set, the rulebook shall
serve as a guide to kick-start play with “default”
suggestions on how to play. However, like the
LEGO instructions, the book should also
encourage players to twist, modify and subvert
the rules, and devise their own ways to play.
7.2. Conclusion Morel proposes a new kind of physical, casual
gameplay, where digital devices are fused with
old-style physical play in an intuitive way. With
no screens to read off of and no buttons to push,
it allows for players to focus on their physical
reality, yet do so in extended ways that were
impossible with playthings of the past.
Through playtesting and evaluation, we were
able to confirm the emergence of many new
kinds of play behaviors. We hope for Morel to
become one of the first of many playthings of its
kind.
8. Achievements • Exhibited Morel in the demo session of
ACM SIGCHI ACE 2006 International
Conference on Advances in Computer
Entertainment, Hollywood, USA, June
14-16, 2006
• Adopted for the 2006 Taikichiro Mori
Research Advancement Fund with the Research Project “Real World
Entertainment Contents for Children’s
Outdoor Play”
9. Acknowledgments I would like to express my appreciation to my
supervisors, Professors Masa Inakage, Yasuto
Nakanishi and Kenji Kohiyama for their advice
and guidance.
I would like to thank the Shonandai Culture
Center Children’s Museum, for their cooperation
in providing playtest spaces and times. I would
also like to thank Hiroki Aramaki, Hiroki
Azuma, Yuichiro Katsumoto, Yoshiyuki Kubo,
Kengo Morooka, Yoshimasa Niwa, Yutaro
Ohashi, Takeshi Osawa, Midori Shibutani, Aya
Shigefuji, Yoshiro Sugano, Eric Taylor, Atsuro
Ueki, Eri Watanabe, Shohei Yamada, Shingo
Yoshida and everyone in the Keio University
Inakage Lab for their cooperation, feedback and
ideas in writing this paper.
This project has been granted by the CREST
project of the Japan Science and Technology
Agency (JST).
10. Supplemental Materials The supplemental CD-ROM contains:
• Video footage from Playtest 1 (December
20, 2005)
• Demonstration Video for submission to
ACM SIGCHI ACE 2006 conference
• Video footage from Playtest 2 (October 17,
2006)
• Photographs and Videos from Playtest 4
(January 6-7, 2007)
• The PDF data of this paper
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