Transcript
ENPH454
Model Maglev Train Group B
Team Leader
Stephan Habicht
Safety Officer Kyle Gamble
Secretary Nick Holt
Treasurer
Jason Pasnak
Mark McCarthy
Andrew McMullen
Nick Green
12/12/2011
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Executive Summary ENPH454 Group B’s objective was to design a miniature model of a Maglev train and track system. The
goal was to construct a Maglev system that would be conceptually equivalent to real world engineering
scenarios which utilize quantum levitation. The final product was designed to be suitable for display
purposes. The propulsion system was designed to control speed and provide braking without contact to
the vehicle. A major project restraint was the $600 CAD budget which severely limited the size of both
the magnetic track and levitating superconductor train car.
The track was three ½”x ½”x ⅛”magnets (magnetized through the thickness of ⅛’’) wide, properly
oriented and laid out to provide a stable ≈1.7 m circular track for the superconductor. The one inch
diameter bismuth strontium calcium copper oxide (BSCCO) superconductor achieved a levitating height
of (3.0 ± 0.5) mm and was used in the final design of the car. The total weight of the car was (6.10 ±
0.05) g and was propelled using a modified linear induction motor (LIM) which resulted in an
acceleration of (0.32 ± 0.03) m/s2, an average speed of (0.38 ± 0.07) m/s, a maximum speed of (0.84 ±
0.07) m/s, and a total run time of 2:47 minutes. This propulsion system employed magnets spinning on
discs which induced eddy currents in aluminum tape on the train car.
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Contents Executive Summary ........................................................................................................................................ i
List of Figures ............................................................................................................................................... iii
1.0 Project Statements & Objectives ............................................................................................................ 1
2.0 Background ............................................................................................................................................. 1
2.1 Levitation Background: ....................................................................................................................... 1
2.2 Propulsion System ............................................................................................................................... 2
3.0 Final Design and Justification .................................................................................................................. 2
3.1 Car Design ........................................................................................................................................... 2
3.2 Track Design ........................................................................................................................................ 3
3.3 Propulsion System ............................................................................................................................... 4
4.0 Construction of Prototypes ..................................................................................................................... 5
4.1 Car Prototype ...................................................................................................................................... 5
4.2 Propulsion System ............................................................................................................................... 5
5.0 Test Results and Analysis ........................................................................................................................ 6
5.1 Average Running Velocity ................................................................................................................... 6
5.2 Running Time ...................................................................................................................................... 7
5.3 Maximum Velocity .............................................................................................................................. 7
5.4 Average Acceleration/Force ............................................................................................................... 7
5.5 Levitation Height ................................................................................................................................. 8
6.0 Troubleshooting and Remediation Efforts .............................................................................................. 9
6.1 Track .................................................................................................................................................... 9
6.2 Propulsion System ............................................................................................................................... 9
7.0 Reflections............................................................................................................................................... 9
8.0 Conclusions ........................................................................................................................................... 10
9.0 Annex ...................................................................................................................................................... 1
9.1 Works Cited ........................................................................................................................................... A1
9.2 References .................................................................................................................................... A1
9.3 Budget ............................................................................................................................................... A2
9.4 Appendix ........................................................................................................................................... A3
9.5 Safety Protocols and Incidence Reports ........................................................................................... A4
9.5.1 Safety Protocols ............................................................................................................................. A5
9.5.2 Safety Issues ................................................................................................................................... A6
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List of Figures Figure 1 - Final design for train car. .............................................................................................................. 3
Figure 2 - Track configuration ....................................................................................................................... 3
Figure 3 – Final Propulsion System ............................................................................................................... 4
Figure 4 - Initial car body dimensions and isometric view of initial car design ............................................ 5
Figure 5 – Initial LIM propulsion system. ...................................................................................................... 6
Figure 6 - Average running velocity of the train car ..................................................................................... 7
Table 1 - Summary of recorded data and initial goals. ................................................................................. 8
Table 2 - Budget summary for Group B’s model Maglev train project ....................................................... A2
Figure 7 - Plot of the maximum speed illustrating the spread in the data. ................................................ A3
Figure 8 - Plot of the average acceleration data. ........................................................................................ A3
Figure 9 - Plot of the average force data. ................................................................................................... A4
Figure 10- Gantt chart showing project progress ....................................................................................... A4
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1.0 Project Statements & Objectives The objective of this project was to exploit the Meissner effect and flux-pinning properties of Type II
superconductors to create a levitating “train” that would travel along a predefined track. Ideally, the
train should have the capability to be accelerated and decelerated by means that minimize contact with
the car. As many components of the system as possible should be scalable for a full size passenger train.
The track must be as long as economically possible and must be a closed loop. Lastly, the entire system
should be fabricated such that it may be used as a teaching aid, with most of the important components
safely visible.
Quantitatively, the car must have an acceleration of 0.25 m/s2 through the propulsion system and a
maximum speed of 0.5 m/s. It should be able to levitate 5 mm above the track and run for at least 1 to 2
minutes without falling or derailing. Through the use of modelling it was decided that train car must also
weigh less than 300g.
2.0 Background
2.1 Levitation Background: Levitation of the train body is achieved through the use of a liquid nitrogen cooled superconductor.
When a superconductor is cooled below its critical temperature, Tc, it behaves as a perfect diamagnet
with zero electrical resistance. It is able to expel nearly all of the magnetic flux. The expulsion of the
magnetic flux causes a force on the superconductor. This force ( ) can be found by integrating the
Maxwell’s Stress Tensor ( ) throughout the surface or an equivalent volume integral through the use of
divergence theorem 1,
This integral was performed through use of computer software in this project. Maxwell’s Stress Tensor is
a rank 2 tensor with its elements given by the following formula (for magnetism only) 1 :
If the superconductor is modeled as a perfect diamagnet (µr = 0), this force would not completely
accurate as it would not account for flux pinning, an effect only seen in high temperature
superconductors. Flux pinning allows magnet flux to penetrate through material imperfections and will
alter the Maxwell Stress Tensor, which ultimately causes a decrease in force. The London Equations
combined with Ampere’s Law gives a second order differential equation that describes the magnetic
field within the superconductor 2,
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In the above equation is called the London Penetration Depth, and is a material parameter. It is one
reason why some superconductors have stronger levitating force than others. A material with a very
small will attenuate the magnetic field to zero at a shorter depth within the material, and will result in
a stronger levitation force.
2.2 Propulsion System The propulsion system for the train was largely based on induced eddy currents. When a conducting
material is immersed in a dynamic magnetic field, a current is induced in the material so as to oppose
the changing magnetic field by generating its own magnetic field. This induced current is called an eddy
current. The magnitude of this eddy current is proportional to the change in the magnetic field as is
given by one of Maxwell’s equations 1,
In the equation above, B is the magnetic field, σ is the conductivity of the material, and J is the current
density that is induced. In the case where the non-uniformity of the magnetic field is generated by a
moving permanent magnet, this equation can be further refined in terms of the velocity of the
permanent magnet and the gradient of the magnetic field as by the chain rule,
is the velocity of the permanent magnet and
is the gradient of the magnetic field in the x-
direction. The current density, J, alters the B-field around the conducting material and in turn produces a
coupled force between the permanent magnets and the conducting material.
3.0 Final Design and Justification
3.1 Car Design The final car was made to be as small and lightweight as possible. Only the Bismuth Strontium Calcium
Copper Oxide (BSCCO) superconductor was used because it could lift much more weight than the
Yttrium Barium Copper Oxide (YBCO) superconductors and has a higher critical temperature. The BSCCO
was approximately 2 grams lighter than the YBCO. A higher critical temperature allows for a longer
duration of levitation.
A block of insulating foam slightly larger than the superconductor was fabricated and hollowed out to
accommodate the superconductor. A small amount of space was left above the superconductor in the
car to make room for liquid nitrogen. Liquid nitrogen can be poured in through a small hole in the lid as
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seen in figure 1. The underside of the lid was constructed to have small protrusions to press the
superconductor to the bottom of the car. Aluminum tape was used to secure the lid to the car body as
well as to provide a conductive surface for use with the propulsion system. The final car design is much
smaller and simpler than the prototype.
Figure 1 - Final design for train car. The hole into which the liquid nitrogen is poured is visible as are strips of aluminum tape.
3.2 Track Design A circular track, three magnets wide, was chosen to be the final track design. The track is approximately
1.7 m in circumference. The track was initially planned to have two straight sections to allow the
propulsion system to have optimal performance. Not enough magnets were ordered to complete the
intended track length, so a circular track was necessary. The track was constructed to minimize the
gradient in the magnetic field along the travelling direction of the superconductor in order to reduce
energy losses. The stability of the track was achieved by maximizing the gradient in the magnetic field in
the transverse direction. 3
Figure 2 - Track configuration. The train travels smoothly in the x direction as the magnetic flux density is relatively uniform. 4
Various modelling and testing was performed on the stability of different magnet configurations and it
was determined that a NSN configuration as seen in figure 2 would provide the required stability with
the maximum lifting force. All two-magnet-wide configurations were rejected due to lack of stability.
Computational modelling in Finite Element Magnetic Methods (FEMM) and with COMSOL supported this
NSN configuration despite greatly exaggerating the magnetic forces involved. However, the trend and
directionality of the modeling agreed with observations. The superconductor is kept in the centre of the
track as there is a local minimum of the magnetic flux density at that location.
The N-45 magnets have the dimensions ½”x ½”x ⅛”. Larger magnets (¼’’ x 1’’ x 1’’) were tested, but it
proved that these larger magnets did not create a very uniform magnetic flux density on the scale of the
size of the superconductor. The gradient of the magnetic flux density causes a loss of energy in the
superconductor due to flux-pinning.
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Steel sheets were added to increase the strength of the magnetic field above the magnets and to
decrease the spacing between them. These plates not only crimp the field, but permit the magnets to be
placed closer together allowing the magnetic field to become more uniform.
3.3 Propulsion System For the final design of the propulsion system a modification of a linear induction motor (LIM) was used.
In this modification the rotating magnetic field was achieved by attaching permanent magnets along the
edge of two spinning discs as seen in the figure 3. The magnets were adhered with epoxy into insets
that were milled along the inside edge of the discs in order to ensure they would not become detached
from the apparatus while spinning. The discs themselves were mounted on an axle that was spun by a
small motor. The motor’s speed and direction could be controlled using a motor controller.
Figure 3 – Final Propulsion System. The permanent magnets along the outside of the disc alternate polarity (N and S) in order to maximize the gradient in the magnetic field.
The orientations of the magnets alternate to maximize the gradient in the magnetic field, which in turn
maximizes the induced eddy currents. Aluminum tape was also attached to the sides of the train car to
serve as a lightweight conducting material for eddy current generation. These induced eddy currents
will generate their own magnetic field to oppose the change in magnetic field that is being experienced
due to the velocity of the permanent magnets relative to the aluminum tape. This can be interpreted as
the train car wanting to remain beside the same permanent magnet for the duration that it is in
between the spinning discs. To do this, the train car must accelerate (or decelerate) to match its speed
with the tangential speed of the permanent magnets on the edge of the disc. As a result of this, the
speed of the train car can be controlled by varying the rotational speed of the discs with the motor
controller.
The spinning disc design was chosen over the linear induction motor for a number of reasons. Chief
among them was the fact that the permanent magnets used had a much stronger magnetic field than
could be produced with the coils in the LIM. The spinning disc design also allowed speed to be
controlled more easily by varying the rotational speed of the discs and with the aid of a reversible motor
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controller, braking could also be achieved. In order to achieve this with the two phase LIM, it would
have been necessary to precisely control the frequency of oscillation as well as the current through the
coils.
4.0 Construction of Prototypes
4.1 Car Prototype After the theoretical calculations from FEMM were made, immediate designs for the train car were
modelled using SolidEdge. Based on the levitation forces which were calculated, the car was projected
to be composed of: three superconductors, a body, and insulation as shown in the figure 4.
Figure 4 - (left) Initial car body dimensions. (right) Isometric view of initial car design
4.2 Propulsion System Two propulsion systems were considered for the maglev train. The first was a LIM which consisted of
screws with coils wrapped around them. The wires were then connected in an alternating fashion to set
the coils 180o out of phase. The first attempt at creating the LIM resulted in a short circuit from the coils
to the aluminum frame due to penetrations in the wire insulation. This was a result of poor protection of
the wire from the sharp edges of the screws. In addition, it was determined that the magnetic circuit
between screws facing one another should be completed in an effort to increase the magnetic field
strength. To achieve this, steel U-shapes were created with the screws through either end such that the
spacing between could be adjusted while still completing the magnetic circuit. This time the wire was
wrapped around the top of the U-shapes rather than on each screw. Aluminum stands were also created
to support these U-shapes above the magnetic track. The propulsion system would work by inducing
eddy currents in an aluminum fin mounted on the car. It was determined that the magnetic field
produced in the coils was much too weak to accelerate the train car forward. In addition, the propulsion
system was too dependent on the slip condition. The slip condition requires that the velocity of the
incoming car be much greater in respect to the frequency of the changing magnetic field between the
coils.
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Figure 5 – Initial LIM propulsion system.
5.0 Test Results and Analysis A number of experiments were conducted in order to characterize the system. The majority of the
experiments involved capturing overhead video footage of the train in a number of different states. The
video was collected using a tripod and a video camera, and it was analyzed using Windows Live Movie
Maker. This video editing software has the advantage that it allows the user to step through video
frame by frame while showing a timestamp on each frame. This feature allowed for accurate
measurement of the train’s motion. The final results were compared to the original design goals which
were set out at the beginning of the project.
5.1 Average Running Velocity The average running velocity is defined as the speed of the train when it is operating under steady state,
with the propulsion system at a constant speed. No user input is required during this mode of operation
beyond the initial setup. The speed was measured at the side of the track opposite to the propulsion
system. The train reaches a steady state after approximately four laps around the track as seen in figure
6. The steady state speed was measured to be (0.376 ± 0.007) m/s. There is an initial ramp-up period
during which the train reaches steady state. These initial points (the first 4) were not used to calculate
the average running velocity. There appears to be a plateau in the first few points, this is believed to
have been caused by the initial user interaction with the car. In an ideal case the data should look
qualitatively like the solid line shown in figure 6.
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Figure 6 - Average running velocity of the train car. An expected speed profile is shown.
5.2 Running Time The measurement of running time was fairly straightforward. After cooling the car to 77K using liquid
nitrogen, the car was drained of any remaining liquid nitrogen (to prevent tipping/spilling). The timer
was started as the car was then set in motion on the track. The timer was stopped when the car could
no longer glide along the track due to the warming of the superconductor. The run time was found to
be 2 minutes 47 seconds.
5.3 Maximum Velocity The maximum velocity of the car is limited primarily its stability on the track. The only force keeping the
car centered on the track is the magnetic force due to the configuration of the magnets. The maximum
velocity was measured by moving the car at varied speeds with the goal of causing the car to gently
escape the track. The video samples used for calculation were those in which the car was stable around
part of the track, but eventually slid off. The maximum speed was taken as an average of 6 values which
gave a result of (0.84 ± 0.07) m/s. A plot of the results can be seen in the appendix.
5.4 Average Acceleration/Force The average acceleration and the average force produced by the propulsion system were also measured
using video analysis. The video was centered over the propulsion system. The velocity of the car was
measured while entering and exiting the propulsion system. The time that the car took to pass through
the propulsion system was also measured using the video. Using basic kinematics, the average
acceleration and the average force were calculated. It is important to note that these are average
values because neither the force nor the acceleration is constant through the propulsion system. In this
sense, the propulsion system is treated as a “black box” where the internal workings are ignored and
only the final result was measured. Both the acceleration and the force measurements were averaged
over 9 sets of data. Plots of this data can be seen in the appendix. The average acceleration was found
0
0.05
0.1
0.15
0.2
0.25
0.3
0.35
0.4
0.45
0 2 4 6 8 10 12 14
Spe
ed
(m
/s)
Pass Number (#)
Ideal curve shape
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to be (0.32 ± 0.03) m/s2. The average force was found to be (2.3 ± 0.3) mN. The force seems quite
small, but due to the small mass of the train car, this is more than enough to propel the car around for
an entire lap.
5.5 Levitation Height The levitation height was another simple measurement to make. A ruler was placed on the inside of the
track and the height of the top of the levitating car was measured. The car was then pressed down on
to the track and the height of the top of the car was recorded again. The levitation height was given by
the difference in these two values. The levitation height was found to be (3.0 ± 0.5) mm.
The above data is summarized in table 1 below. Included in the table are the design goals put forth at
the beginning of the project. Four of the five proposed goals were achieved; the only goal which was
not achieved was the levitation height. This goal of 5 mm was based on a number of factors including
preliminary testing, finite element modelling, as well as a survey of similar projects. Ultimately, the
limitation was the strength of the magnets and the weight of the car. The magnets were the best option
within the budget and the train car was kept as light as possible by using only aluminum foil and
polystyrene foam. Access to better materials could have allowed the project goals to be met, but
ultimately the achieved height of 3mm was sufficient for normal operation of the train. One other point
worth mentioning is that the goal of keeping the train car mass under 300g was overly lenient in
hindsight. However, based on the finite element modelling, it was expected that the superconductor
would be able to produce several Newtons of lift force. The train mass was eventually reduced to the
final value of 6.1g after it was discovered that the real lift force was orders of magnitude less than that
predicted by the modelling.
Table 1 - Summary of recorded data and initial goals.
Goal Achieved
Acceleration (m/s2) 0.25 0.32 ± 0.03
Average Speed (m/s) - 0.38 ± 0.07
Maximum Speed (m/s) 0.500 0.84 ± 0.07
Levitation Height (mm) 5 3.0 ± 0.5
Train Mass (g) <300 6.10 ± 0.05
Run Time (min) 1-2 2:47
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6.0 Troubleshooting and Remediation Efforts
6.1 Track Because magnets facing in the same direction repel each other, trying to make the spacing between the
magnets along the track proved difficult. When the track was first laid down, the gap between each set
of magnets was about 0.5cm. When the train was levitated above the track and given a push, it slowed
down quickly due to the irregular magnetic field caused by the gaps in the magnets. The magnet spacing
needed to be minimized to make the magnetic field as even as possible.
To make it more difficult for the magnets to push away from each other, the surface of the metal base
was roughened with sandpaper. This increased the friction between the magnets and the metal base,
allowing the magnet spacing to be reduced. When this was done the magnets were able to be placed
closer, but not close enough to allow the superconductor to travel without significant energy loss.
To try to further increase the friction force on the magnets, the base plates were placed on top of a thick
sheet of steel. The magnets were able to stick much more strongly to the track when the steel was
placed underneath the base plate. The combination of the thick sheet of steel and the roughened
surface made it possible to push the magnets so that most of the magnets were touching. This made the
magnetic field above the track very smooth, minimizing the energy loss of the car due to uneven
magnetic fields.
6.2 Propulsion System During the construction of the propulsion system many obstacles were encountered. The second
propulsion system will be discussed because troubleshooting was required to make the system work.
Initially magnets were to be attached to the car with eddy currents being induced in the copper discs
and thus propelling the car forward. However, due to weight restrictions of the car, the system was
inverted. Small metal fins were created to attach to the sides of the car and the magnets were inset and
adhered to the rotating discs. However, troubleshooting was required because the superconductor was
unable to levitate the car with the added weight of the aluminum fins. Thus, aluminum tape was used
to seal the car together and be used for propulsion. The tape was lightweight and more could be added
or removed to fine-tune the propulsion system. Finally, a Teflon bearing was created to be attached to
the opposite end of the shaft of the motor to help maintain smoother and truer rotation. With these
modifications, a working propulsion system was achieved.
7.0 Reflections In review of this project, there are a few things that could have been done differently. During the
magnet testing phase, multiple test sets could have been ordered at once to streamline the process.
This would allow for the magnets to be tested at the same time, instead of one after another.
Upon testing of the two superconductors that were purchased, the BSCCO was clearly a better material
for levitation than YBCO. In the end the YBCO was not used in the final construction of the train car due
to its low critical temperature and higher density, making it an unnecessary expense other than for
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testing and comparison purposes. This portion of the budget could have been used to purchase another
BSCCO superconductor or to extend the track through purchasing more magnets.
One area of future work would be to make the system more automated. The motor controller could be
computer controlled which would allow for precise speed control and automated braking.
8.0 Conclusions Overall the project was a success. A type II superconductor was used to create a levitating train that
travels along a track of permanent magnets. The train was accelerated and decelerated using a single
non-contact system. Four out of five of the original five design objectives were met. The only objective
which was not achieved was the levitation height. The expected levitation height of 5 mm was based on
the modelling, which was later found to be a severe overestimate. The achieved height of 3 mm was
still sufficient to meet the rest of the design goals. The project was under budget and finished on
schedule as seen in the Gantt chart in the appendix. Safety was considered in all parts of the design;
most notably, barriers were included near any moving parts. The overall design was transparent to
ensure that the functionality would be apparent to allow usage as a demonstration.
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9.0 Annex
9.1 Works Cited 1. Griffiths, D., Indtroduction to Electrodynamics, 3rd ed. (Pearson Addison-Wesley, New Jersey, 1999).
2. London, F. L. a. H., Proceedings of the Royal Society of London. Series A, Mathematical and Physical
Sciences (1935).
3. Strehlow, C. P. & Sullivan, M. C., A Classroom Demonstration of Levitation and Suspension of a
Superconductor over a Magnetic Track. Department of Physics, Ithaca College (2008).
4. Yang, W. M., Zhou, L., Yong, F., Chau, X. X. & Bian, X. B., A small Maglev car model using YBCO bulk
superconductors. Semiconductor Science and Technology 19, S-537 to S-539 (2006).
9.2 References
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9.3 Budget
Table 2 - Budget summary for Group B’s model Maglev train project
Item Description Cost
1 Levitation Comparison Kit
Boreal Northwest
1 x 2.5 cm YBCO disc. 1 x 2.5 cm BSCCO disc. 2x rare earth magnets
1 x non-magnetic tweezers and manual
Item Value $135.00
Shipping/Handling $8.00 Total
$143.00
2
10 Neodymium Block
Magnets (Test Magnets)
Zigmyster Magnets
1/8’’ x 1/2’’ x 1/2’’, N45, Ni coated magnets. Magnetized
through thickness (1/8’’)
Item Value $10.50
Shipping/Handling $8.00
Total
$18.50
3 10 Neodymium Block
Magnets (Test Magnets)
Zigmyster Magnets
1/4’’ x 1’’ x 1’’, N45, Ni coated magnets. Magnetized
through thickness (1/4’’)
Item Value $39.00
Shipping/Handling $10.50
Total
$49.50
4 400 Neodymium Block
Magnets (Final Decision)
Zigmyster Magnets
1/8’’ x 1/2’’ x 1/2’’, N45, Ni coated magnets. Magnetized
through thickness (1/8’’)
Item Value $352.00
Shipping/Handling $23.50
Total
$375.50
TOTAL COSTS - $586.50
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9.4 Appendix
Figure 7 - Plot of the maximum speed illustrating the spread in the data.
Figure 8 - Plot of the average acceleration data.
0
0.2
0.4
0.6
0.8
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1.2
0 1 2 3 4 5 6 7
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ed
(m
/s)
Pass Number (#)
Data Points Average
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0.1
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0 2 4 6 8 10
Acc
ele
rati
on
(m
/s^2
)
Pass Number (#)
Experimental Avg
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Figure 9 - Plot of the average force data.
Figure 10- Gantt chart showing project progress
9.5 Safety Protocols and Incidence Reports In every engineering project safety should be of vital importance. In the case of the Maglev Train, all
precautions were be taken so that all parties involved were protected from any potential hazards
located in and around the construction area. To ensure that the safety of students, teaching assistants
and professors working in the laboratory area, the Maglev Train team created safety protocols and
procedures for the hazardous materials on the site. These materials included: liquid nitrogen,
neodymium magnets, Cryogel, and superconductors. In addition, two forms were created: a safety
0
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1.5
2
2.5
3
3.5
0 2 4 6 8 10
Forc
e (
mN
)
Pass Number (#)
Experimental
Average
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release form and a incident report form. These protocols and forms are discussed below. Lastly, safety
issues that arose throughout the project are also discussed below.
9.5.1 Safety Protocols The safety protocols inform the reader to read the safety precautions page of the particular item he or
she is working with. The safety precautions outline the hazards that can be present in the handling,
storage and transportation of the particular item. In addition, the protocols provided information on
the nearest first-aid kits, what to do if first-aid or medical attention is required and inform the person to
follow the safety precautions or the handling neodymium magnets or liquid nitrogen may be prohibited.
The safety handout for Stirling Hall was also included in the safety section of the binder as it contained
useful information on the location of various safety equipment (i.e. first-aid kits and artificial
respirators).
The safety protocol and safety precaution page for liquid nitrogen can be found at the end of this
section. In addition, the MSDS for liquid nitrogen was also available for additional information and to be
provided to medical personnel in the event of an incident. The main risks associated with liquid
nitrogen is burns to skin and splashing into the eyes. For safety purposes, the proper personal
protective equipment (PPE) was worn when pouring liquid nitrogen. The PPE consisted of goggles or
safety glasses and cryogenic gloves. If cryogenic gloves were not present care was taken to pour
without gloves. This is due to the fact that permeable work gloves would allow the liquid nitrogen to
soak through and remain in contact with the skin causing severe burns. If liquid nitrogen comes in
contact with bare skin it will evaporate before causing any damage.
The safety protocol and precaution page can be found at the end of this section .The MSDSs of all the
constituent materials except neodymium used in the rare-earth magnets are also included. The other
materials used are boron, iron and nickel. Nickel was used as a protective coating. An MSDS for
neodymium was unable to be found due to minimal research. The main safety concern with
neodymium magnets is pinching. To avoid pinching gloves are worn while handling the magnets. With
the small magnets chosen for the full track, pinching hazards were minimized as the size of these
magnets essentially eliminated the possibility of pinching.
The MSDS for Cryogel was included with the shipment of Cryogel samples. Although the completed
project did not include any Cryogel, safe handling procedures were required during testing. The two
safety concerns associated with Cryogel was skin irritation and the creation of dust. Prolonged skin
exposure to the fibres in the Cryogel sheets would irritate the skin due to the roughness. Excessive
bending of the Cryogel sheets could have led to the creation of dust particles of the insulation which
could pose respiratory problems due to inhalation. Therefore gloves were worn during the handling of
the insulation samples.
The MSDSs for the two different superconductors (YCBO and BSCCO) were available on site. To avoid
health risks the superconductors were carefully transported to avoid breakage which could lead to
harmful dust. In addition, the superconductors were wiped clean of any condensation after the
superconductor had heated up after being super cooled.
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Additional forms were created for safety purposes by the Maglev Team. The first form was a safety
release form that outlined every member of the team filled out to ensure that they had read and
understood the safety protocols, procedures and MSDSs of all the hazardous materials present at the
project location. The second form was a blank incident report form to be filled out in the event of a
safety related injury. A copy of the two forms can be found in Safety Protocols and Incident Reports
Section in the annex of this report. The Maglev Train team would like to proudly announce that there
were no safety injuries throughout the duration of the project.
9.5.2 Safety Issues This section describes safety issues that arose during the construction and testing phase of the project in
which safety measures were put in place. The two areas in which safety risks presented themselves was
with the propulsion system. Two safety issues arose, the danger of exposed discs spinning at high
revolutions per minute and the potential risk of high speed projectiles.
The second phase of the phase of the propulsion system consisted of discs rotating at high rpm with
small magnets inset into them using epoxy. To avoid people from touching the discs with their hands
and to have loose clothing become entangled with the shaft a Plexiglas box was created to still provide a
viewing window such that the propulsion system can still be analyzed from a demonstration perspective
while operating in a safe manner.
Lastly, due to the magnets being inset on the rotating discs, the possibility of one coming loose and
flying at high speeds had to be minimized. This was done by ensuring the magnets were inset and glued
with high strength epoxy. Another projectile risk is if the lightweight car was to come in contact with
the discs and be flung at high speeds. This is minimized due to the protective box as well as the
cardboard barrier around the perimeter of the track to stop the car if it was to exit the track.
The following pages have the safety protocols and procedures for neodymium magnets and liquid
nitrogen as well as the safety release form and blank incidence report form. The MSDSs of the materials
are not included here and are found in the safety section of the project binder.
A7
Safety Protocol for Liquid Nitrogen
1. Read through the document entitled Safety Precautions with Liquid Nitrogen before proceeding
to handle Liquid Nitrogen.
2. Liquid is an extremely cold liquid and certain hazards are present. These are outlined in the
document listed above and in the MSDS which can be found in the safety section of this binder.
3. If first-aid is required inform the supervising professor (Dr. Gao or Dr. Morelli) and obtain the
required treatment. Note that the certified first-aid person on the fifth floor is Steve Gillen in
room 502. The nearest first-aid kits are located between rooms 507 and 508 and in 502.
4. If oxygen levels are depleted use an artificial respirator to access and safely turn off the source
of nitrogen. Do this only if it is safe to do so.
5. If medical attention is required bring the MSDS to the hospital and provide the doctor with
these. This will allow the doctor to determine which treatment is best.
6. Follow the instructions of the safety officer for Group B. If you are violating the safety
precautions you will be warned and handling of liquid nitrogen may be prohibited.
Safety Protocol for Neodymium Magnets
1. Read through the document entitled Safety Precautions with Neodymium Magnets before
proceeding to handle them.
2. The magnets are composed of Neodymium, Iron and Boron and are coated in Nickel. The
MSDS's for all these constituent compounds except Neodymium are available in the safety
section of this binder. Neodymium has not be studied extensively enough to produce an MSDS.
3. If first-aid is required inform the supervising professor (Dr. Gao or Dr. Morelli) and obtain the
required treatment. Note that the certified first-aid person on the fifth floor is Steve Gillen in
room 502. The nearest first-aid kits are located between rooms 507 and 508 and in 502.
4. If medical attention is required bring the MSDS's to the hospital and provide the doctor with
these. This will allow the doctor to determine which treatment is best.
5. Follow the instructions of the safety officer for Group B. If you are violating the safety
precautions you will be warned and handling of magnets may be prohibited.
A8
Safety Precautions with Liquid Nitrogen
Handling and Storage
Liquid Nitrogen is extremely cold and can cause severe burns causing living tissue to instantly
die.
Cryogenic gloves , long pants that go over top of the shoes and safety goggles must be worn
when dispensing liquid nitrogen. If someone is using a tipper device to pour liquid nitrogen a
full face shield is required over the goggles. If cryogenic gloves are unavailable, use bare hands
with extreme caution.
When dispensing liquid nitrogen DO NOT use a funnel. If a funnel is used it can freeze and force
liquid nitrogen into your face.
Do not store liquid nitrogen in areas where there is no air exchange as the elevated levels of
oxygen can cause anyone entering the room to pass out and die without any warnings.
Liquid nitrogen condenses oxygen from air. Care must be taken to ensure that liquid oxygen
does not build up as it is highly flammable and can cause an explosion hazard.
On a Dewar that is holding liquid nitrogen ensure there is no build up of pressure by using a
pressure relief valve for lid vent.
Before handling liquid nitrogen ensure that all jewellery and watches are removed. Liquid
nitrogen can freeze these items to the skin if contact is made.
If enough liquid nitrogen vapourizes bringing the concentration of oxygen in the area below
19.5% by volume asphyxiation can occur due to oxygen deprivation.
Use Dewars that are rated for extremely cold temperatures.
Never carry liquid nitrogen in a passenger elevator as the potential risk of injury is greatly
elevated.
The precautions listed here are found on Purdue's chemistry department website at
<http://www.chem.purdue.edu/chemsafety/chem/ln2.htm>
A9
Safety Precautions with Neodymium Magnets
Handling
Ingestion of neodymium magnets is extremely hazardous. If magnets are ingested or
inhaled into the lungs, immediate medical attention is required.
Neodymium magnets are fragile and can shatter easily.
Neodymium magnets are powerful and can accelerate at high rates toward one another
or other ferrous material and can shatter on impact creating high speed particles.
If skin is caught in between two magnets or a magnet and a ferrous material will pinch
strongly causing injury.
Gloves and Safety glasses/goggles should be worn when handling neodymium magnets.
Very large neodymium magnets pose a crushing hazard and should not be handled.
Magnets should never be used to lift objects over people.
The magnetic field produced by neodymium magnets can damage electronic equipment
and storage devices. Keep laptops, credit cards, USBs and other electronics away from
the magnets.
DO NOT burn neodymium magnets as they can ignite and burn at high intensities.
DO NOT drill or machine neodymium magnets as hazardous flammable powder may
form and the risk of shattering is elevated.
DO NOT use neodymium magnets in contact with food and other ingestible liquids.
Neodymium magnets are susceptible to oxidization. Dispose of oxidized magnets.
Health Effects
Individuals with internal medical devices should consult their physician prior to handling
neodymium magnets as the static magnetic fields may affect the operation of the
device.
Disposal
Neodymium magnets should be disposed according to local, provincial and federal laws.
Thermally demagnetize neodymium magnets before disposal.
Alternatively place magnetized magnets in a steel container prior to disposal.
Information in this document is provided by National Imports Magnetic Products Division, which
is a US based company specializing the production of rare-earth magnets.
<http://www.rare-earth-magnets.com/t-safetyinformation.aspx>
A10
Acknowledgement of Hazards Form
I ___________________ hereby agree, that by checking the above boxes I am aware of the
hazards associated with the materials in and around the Maglev Train area. I also agree that any
injury resulting in my failure to abide by the precautions and protocols is my own fault and does
not hold the Safety Officer accountable as I was informed of the hazards.
For all other hazards (high voltages, high speed masses, etc.) consult a teaching assistant, professor
or qualified technician to ensure safety is maximized before proceeding. Any conditions in which the
hazards are unknown should also be examined by a qualified person.
Other Hazards:
Neodymium Magnets (Check all that apply):
Note: If not all the above boxes are checked you will not be allowed to handle Neodymium Magnets.
Are you aware of the dangers?
Are you aware of the PPE required?
Have you read the safety
precautions?
Have you read the safety protocol?
Note: If not all the above boxes are checked you will not be allowed to handle Liquid Nitrogen.
Are you aware of the dangers?
Are you aware of the PPE required?
Have you read the safety
precautions?
Date: _______________________
Date: _______________________
Date: _______________________
Team Member: ____________________ Safety Officer: _____________________
Liquid Nitrogen (Check all that apply):
Team Member Signature: ________________________
Safety Officer Signature: _________________________
Have you read the safety protocol?
A11
Safety Incident Report
Date: _______________________ Team Member: ____________________
Safety Officer: _____________________
Where did the injury occur? (i.e student shop, lab): ______________________________
Description of the injury:
___________________________________________________________
___________________________________________________________
___________________________________________________________
___________________________________________________________
Team Member Signature: ________________________
Safety Officer Signature: _________________________
Have you read the safety protocols?
Have you read the safety precautions?
Were you wearing the proper PPE?
Were you aware of the dangers?
Comments:
_______________________________
_______________________________
_______________________________
YES
Date: _______________________
Date: _______________________
Detailed explanation of what caused the injury: ___________________________________________________________
___________________________________________________________
___________________________________________________________
___________________________________________________________
NO
Indicate on the body where the injury occurred.
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