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Practices and Improvements of Lesson using Magnetic field Visualization by Mixed Reality (MR) technology

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Practices and Improvements of Lesson using Magnetic field Visualization by Mixed Reality (MR) technology

Abstract and Figures

It is difficult to study the phenomena which cannot be seen. But Mixed Reality (MR) has the potential to support such study. In this case, I take magnetic fields as the phenomenon cannot be seen. I created and improved a visualization teaching application and lesson program to resolve several problems which become apparent through lesson practices. At last the learning effect was confirmed and the satisfaction was very good. In this research, I confirmed that with devises MR is able enough to support the study of phenomena cannot be seen, and I confirmed the requirements to do lesson using MR.
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Practices and Improvements of Lesson using Magnetic field Visualization
by Mixed Reality (MR) technology
UEDA Tatsuro
Mie University part time lecturer
ueda.tatsuro@gmail.com
Abstract
It is difficult to study the phenomena which cannot be seen. But Mixed Reality (MR) has the
potential to support such study. In this case, I take magnetic fields as the phenomenon cannot
be seen. I created and improved a visualization teaching application and lesson program to
resolve several problems which become apparent through lesson practices. At last the learning
effect was confirmed and the satisfaction was very good. In this research, I confirmed that
with devises MR is able enough to support the study of phenomena cannot be seen, and I
confirmed the requirements to do lesson using MR.
Keywords
Mixed Reality, MR, Augmented Reality, AR, Magnetic Field, Visualization, ICT,
Information technology
1. Background
1) Study of phenomena cannot be seen
It is difficult for students learning physics to
study and understand the phenomena which
cannot be seen.
Thus, how to image the phenomena cannot
be seen is important in the study of physics.
In this research, I confirmed that MR
information technology is a efficient method
of visualization and imagination, using the
teachings of magnetic fields as an example.
2) Study of magnetic field
Fig. Iron sand around a bar magnet
Magnetic field cannot be seen.
In this research, I created the teaching
material with MR technology which includes
AR to study magnetic fields.
3) Augmented Reality (AR)
Fig. Famous game using AR
(Pokemon Go)
Augmented Reality (AR) is a variation of
Virtual Reality (VR). VR technologies
completely immerse a user inside a synthetic
environment. While immersed, the user
cannot see the real world around him. In
contrast, AR allows the user to see the real
world, with virtual objects superimposed
upon or composited with the real world.
Therefore, AR supplements reality, rather
than completely replacing it. Ideally, it
would appear to the user that the virtual and
real objects coexisted in the same space
[Ronald, 1997].
Various sensors such as camera, GPS or
acceleration sensor make tracking the
position and orientation of a mobile phone
possible. And this system can display an
image in the correct position and orientation,
and is important technology to realize AR.
We can use image recognition libraries such
as "ARToolKit" released in 1999 for AR
tracking.
Fig. Example of using
AR library
Dieter Schmalstieg and Daniel Wagner
developed the first real time marker tracking
system for mobile phone and personal
digital assistant (PDA) in 2003.
Fig. The first real time marker
tracking system
for mobile phone and PDA
4) Mixed Reality (MR)
MR in recent years
The original concept of Mixed Reality (MR)
was put forward in the 1990's. However, the
Mixed Reality headset in recent years (after
2016) has the following appearance (the
picture is HoloLens).
Fig. Appearance of MR headset
In the case of VR, a headset is a closed,
immersive type. You can see only virtual
images in three dimensions. On the other
hand, the MR head set is transparent type
(see-through). The wearer can see both the
virtual stereoscopic image and the
surrounding scenery at the same time.
In the case of MR, a headset can grasp the
wearer's gaze direction, posture and
movement in real time. Even the wearer
changes his/her gaze direction, posture or
he/she moves, it seems to him/her that the
virtual stereoscopic image is "placed" in real
space.
Fig. A man operating in MR
Fig. People working together in MR
In brief, when we wear a MR headset, we can
mix real scenes and virtual images and see
them. Therefore, it is called Mixed Reality.
History of MR
Historically, the first concept of MR was
proposed by Milgram et al. (1994):
An MR experience is one where the user is
placed in an interactive setting that is either
real with virtual asset augmentation
(augmented reality, AR) or
virtual with real-world augmentation
(augmented virtuality, AV) that
overlays real information on a virtual
world.
Fig. First definition of MR
Huges (2005) embodied the concept of MR:
MR is the mixed visual and audio content for
both
AR (such as image, sound, smell, heat.
The left side of the figure below) and
AV (Virtual world overlaid with
information from real world obtained
with such as camera and sensors. The
right side of the figure below)
which is captured, rendered and mixed by
graphics and audio engines.
Fig. MR as mixed of AR and AV
In this case, actual images are supposed to
be acquired from the camera. This is a bit
different from the current one.
Adriana et al. (2009) sophisticated the
definition of MR:
MR is the merging of real and virtual worlds
to produce new environments and
visualizations where physical and digital
objects co-exist and interact in real time.
They removed the somewhat confusing
concept of AV from MR and added real
space instead (the meaning has not
changed). They also emphasized spatiality,
interactivity and real-time nature.
5) MR and physics education
Fig. 10 Physical phenomena
with additional image
In many cases of physics study, we learn the
mechanics of phenomena around our
everyday life.
Therefore, if we can add information such as
images of vector with color to the real world
around us (e.g. running car, current carrying
electric wire, air of a room), it is efficient for
physics study.
*** References of AR visualization ***
*** Comparison with AR and MR ***
So, MR can do this, that it is suitable for
physics study.
Unfortunately, I couldn’t add information
directly to real phenomena in this research,
but I created MR teaching materials able to
operate and experience virtual phenomena.
2. Purpose of research
The purpose of this research is, to confirm
the requirements that the teaching
application and lesson program using MR
should satisfy by performing lesson practices,
for learning phenomena cannot be seen and
are difficult to understand but popular
around everyday life especially learning
magnetic field.
3. Methods
1) Improvement of teaching application and
lesson program
I confirmed problems in every lesson to
analyze responses of students and the results
of the post questionnaire. Afterwards, I
improved the teaching application and
lesson program to overcome confirmed
problems.
2) Evaluation of efficiency
Learning effect
I carried out learning tests to write
directions of magnetic field before and after
lesson, and compared scores.
Degree of satisfaction
I measured students' satisfaction of MR
lesson by NPS (Net Promoter Score).
Fig. 11 How to calculate NPS
NPS is the index to measure attachment,
reliance and satisfaction degree of
corporation, brand and service. It has been
widely adopted with more than two thirds of
Fortune 1000 companies using the metric
(Jennifer, 2016).
It is calculated based on responses to a single
question:
"How likely is it that you would recommend
our company/product/service to a friend or
colleague?"
It can be as low as −100 (everybody is a
detractor) or as high as +100 (everybody is
a promoter). In many case NPS is negative
(i.e., lower than zero), and positive NPS (i.e.,
higher than zero) is felt to be good, and an
NPS of +50 is top level in the industry.
4. Results
1) Improvement of teaching application and
lesson program
Version 1
Fig. 12 Appearance of version 1
Description
Only 3-dimensional magnetic force lines are
drawn around a virtual bar magnet. Because
it is a stereoscopic image of MR, it can be
watched from any angle by walking around
freely. But the magnet cannot be moved.
Practice
I provided a demonstration in HoloLens
meetup Osaka the first time.
Problems
After watching 3-dimensional magnetic
force lines, it is still intuitively difficult
to understand the circumstances of a
magnetic field.
There is little reality because the magnet
is unable to move and the magnetic field
does not change.
Version 2
Fig. 13 Appearance of version 2
Description
A user can move a virtual bar magnet
limitedly by moving the paper on which
special pattern is printed. The application
doesn't draw magnetic force lines but
arranges many virtual azimuth needles 3-
dimensional grid pattern. Each azimuth
needle points in each direction according to
the position of the bar magnet. Azimuth
needles are bright where a magnetic force is
strong, and dark where a magnetic force is
weak.
Therefore, this teaching material can
express both the direction and the strength
of a magnetic field.
In addition, when an azimuth needle rotates,
it makes sounds.
Improvements
Since magnetic force lines are difficult to
understand, I introduced azimuth needles
representing the state of the magnetic field
(At first FPS - Frames Per Second - fell to 5,
but I improved performance). It is easier to
understand for users who are able to move
the bar magnet, so I made it possible. I
adopted the AR marker for this reason.
Response
I tweeted a new app's video, and the tweet
was retweeted 400 times. Also, I was
interviewed by net news dealing with VR.
Practices
Fig. 14 Exhibition of DIY mindset
(Osaka Maker's Bazaar)
I exhibited the MR teaching material at the
exhibition of DIY mindset (Osaka Maker's
Bazaar) and 60 visitors experienced it.
Problems
It was confirmed from experienced people's
responses and free description on a
questionnaire that there were problems as
follows:
Operability and visibility are not good
The operation is not stable (The
recognition of AR marker is often lost).
Direction such as sound is not good
(Noisy).
Version 3
Fig. 15 Appearance of version 3
Description
A user can move a virtual bar magnet by a
gesture to move his/her hand in front of
him/her. Azimuth needles are arranged in 2-
dimensional and 3-dimensional grid pattern
which rotate with the movement of the bar
magnet and change their brightness with the
strength of the magnetic force. In addition,
when a user operates the bar magnet, it
makes sounds according to the operation
state.
Improvements
Because the operability of the bar magnet
was bad, I changed the operation method
from AR to hand tracking. And also, I added
the operation sound to improve operability
on.
Practices
Fig. 16 Exhibition of DIY mindset
(Maker Faire Tokyo 2017)
I exhibited the MR teaching material at the
exhibition of DIY mindset (Maker Faire
Tokyo 2017) and 54 visitors experienced it.
Fig. 17 Suzuka High School
Because responses were very good, I next
practiced lessons in the high school (Suzuka
High school, Mie, Japan). 73 students took
my lessons.
Responses
The teaching material was experienced
individually in the exhibition, and the
response was very good. So, I finished the
individual phase and entered the lesson
practice phase. I practiced lessons using MR
teaching material in a high school, and found
a few problems.
Problems
There were problems as follows:
The live video on a projector is small and
difficult to watch (Objects displayed
must be bigger).
Because there is a long time-lag between
the experience and the live video
displayed by projector, it is difficult to
catch up with the lecture (The time lag
must be shorter).
The behavior is slow (The program must
be optimized more).
Version 3.5
Fig. 18 Appearance of version 3.5
Description
I added the features below to version 3.
There is a gradation of color and it moves
from the south pole of the azimuth needle to
the north pole. A user can display magnetic
force lines.
In the scene of 3-dimension, at first, the bar
magnet automatically does reciprocating
motion slowly. A user can observe how
azimuth needles rotate by the reciprocating
motion of the bar magnet. This makes the
understanding of a 3-dimension magnetic
field easy.
In addition, I let students confirm the
behavior of real magnets before and after the
experience so that they could connect real
and virtual.
Improvements
I made the Azimuth needle bigger to make it
easy to watch the live video on the projector.
I changed the way of displaying the live
video on the projector and make the length
of time lag shorter. I optimized the program
(I wrote the shader directly) to make it work
faster.
I also improved as follows:
Display of magnetic force lines
Addition of Azimuth needle animation
Automation of the reciprocating motion
of the bar magnet in 3-dimensional
scene
Practices
Fig. 19 Mie High School
I practiced lessons in the high school (Mie
High school, Mie, Japan). 52 students took
my lessons.
Figure X Prefectural Aichi High School of
Technology and Engineering
I practiced lessons in the high school
(Prefectural Aichi High School of
Technology and Engineering, Aichi, Japan).
29 students took my lessons.
I practiced lessons in the junior high school
(Inagi Civic 6th Junior High School, Tokyo,
Japan) (No picture). About 180 students
took my lessons.
Fig. 20 Kyoshin School One
Yokkaichi Tokiwa
I practiced lessons in the private-tutoring
school (Kyoshin School One Yokkaichi
Tokiwa, Mie, Japan). 5 students took my
lessons.
Fig. 21 IT College for Handicapped
I practiced lessons in the IT skill
development school for handicapped people
(IT College for Handicapped, Mie, Japan).
19 students took my lessons.
Responses
Lessons were popular in all schools. In
addition, because the satisfaction of
experienced students was much higher than
other students, I let all students experience,
so that the global satisfaction became
higher.
On the other side, many students got
interested in magnetic field. For example,
many junior high school students said "I am
looking forward to lessons on magnetism".
Problems
When I let all students experience MR, they
see similar live video many times, so that
they get tired in about 20 minutes (A devise
to avoid students from getting tired is
necessary).
Version 4
Fig. 22 Appearance of version 4
Description
I added the features below to version 3.5.
More than one student can see and operate
the same 3-dimensional image together.
When a student moves his/her bar magnet,
other students can see the movement.
Because students each operate one bar
magnet, the number of bar magnets in the
space is same as the number of students. In
brief, students share one mixed reality space.
Azimuth needles arranged in a grid pattern
are affected by more than one bar magnet,
so rotate and change brightness in real-time.
Also, magnetic force lines are affected by
more than one bar magnet, so the form
changes in real-time.
Improvements
Because students share the same mixed
reality space, the live video on the projector
is not similar but changes every time, so that
I can avoid students getting tired.
Practices
I provided a demonstration in Asahi
Shimbun Publishing Co. (dealing with
newspaper). Two members of staff
experienced the lesson.
I provided a demonstration in Benesse Co.
(dealing with education). Six members of
staff experienced the lesson.
Fig. 23 Tsu Higashi High school
I practiced lessons in the high school (Tsu
Higashi High School, Mie, Japan). 31
students took my lessons.
Responses
Each demonstration and the Lessons were
popular.
As my objective impression, the dimension
of experience would change higher when
people share same mixed reality space.
2) Learning effect
At Suzuka High School where I took the first
lesson, the score of the learning test rose
16% after the lesson. At Mie High School,
the score rose 40%. At other schools where I
carried out learning tests, scores rose too.
Satisfaction score of experience
The NPS answer distribution at the
exhibition on June 2017 (Osaka Maker's
Bazaar) is as below:
Fig. 24 NPS answer distribution at
Osaka maker's bazaar
NPS was -41. It can be said that the
satisfaction level was low.
Then, NPS answer distribution at the high
school on February 2018 (Mie high school)
is as below:
Fig. 25 NPS answer distribution at Mie
high school
NPS was 0. It can be said that the
satisfaction level was normal or a little high.
Then, NPS answer distribution at the high
school on March 2018 (Prefectural Aichi
High School of Technology and
Engineering) is as below:
0
5
10
15
20
0 1 2 3 4 5 6 7 8 9 10
Number of persons
0
5
10
15
0 1 2 3 4 5 6 7 8 9 10
Number of persons
Fig. 26 NPS answer distribution at
Prefectural Aichi High School of
Technology and Engineering
NPS was +50. It can be said that the
satisfaction level was very high.
Thus, by improving the teaching material
application and the lesson program, it
turned out that the students were satisfied in
very high level.
5. Conclusion
1) The requirements of teaching
application and lesson program about
magnetic fields with MR
Based on the above results, the
requirements to be satisfied by the teaching
materials and the lesson program on the
magnetic field using MR in actual class can
be summarized as follows:
Because It is difficult to understand with
only magnetic force lines, another
devise to express a magnetic field (i.g.
azimuth needles arranged in a grid
pattern) is required.
Because a static magnetic field is
difficult to understand, it must be
possible to experience a dynamic
magnetic field.
2) The requirements of teaching
application and lesson program with MR
In addition, more generally (even in unit
learning other than magnetic field), in order
to do lesson using MR in an actual class (i.e.
50 minutes 40 people), the following devises
are required:
If the operation is not stable (i.e. the
marker tracking is often lost), the
experience becomes annoying.
To display to many people by projector,
objects displayed must be big
Because the time lag between
experience and live video displayed by
projector arrests understanding, it must
be short.
If the behavior is slow, the experience
becomes annoying.
To let the satisfaction be at high level, it
is necessary that everyone experience
MR.
If students see similar live video many
times they get tired, so a devise to avoid
them getting tired (i.e. more than one
student can share one mixed reality
space) is required.
3) Learning effect and degree of
satisfaction
The scores of the learning test rose. It can be
said that the teaching of magnetic fields
using MR has learning benefits.
Many students got interested in magnetic
field. It can be said that the lesson of
magnetic field using MR is effective to
attract students' interests. Therefore, for
example, to perform MR lesson at the
0
5
10
15
0 1 2 3 4 5 6 7 8 9 10
Number of persons
beginning of the unit considered to have a
good effect.
About the degree of satisfaction, it was very
high when students took lessons which
satisfy the aforementioned requirements.
The timing when we can carry out the lesson
of magnetic field using MR is limited, but
the lesson can be said to be better to carry
out at the timing.
4) Another problem and solution
MR headsets are still in the development
phase and very expensive. The price is
predicted to decrease, but it is considered
difficult for schools to purchase them in a
few years. Therefore, the way that
organizations able to carry out lessons using
MR independently deliver lessons to schools,
is considered to be realistic.
6. Future work
The true value of MR in learning physics is
that, by the addition of stereoscopic image
to physical phenomena which we cannot
watch, we can visualize those phenomena. It
is considered that if real world and
stereoscopic image are connected with each
other, we can feel high reality.
Presently, I visualize the magnetic field, but
the bar magnet does not exist in the real
world. In other words, I don't visualize the
magnetic field around a real bar magnet.
The future work is to provide experiences
with higher reality by a directly visualizing
the magnetic field around a real bar magnet.
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D.E.Hughes, Defining an Audio Pipeline for
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(2005)
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ResearchGate has not been able to resolve any references for this publication.