Thermal Sensor Cluster Engineering Report Summary

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Thermal Sensor Cluster
Engineering Report
ME 189 - Team 3A
Kai Moncino - Ben Swan - Brenden McMorrow - Joe de Rutte – Riley Borrall
Rev. Date: March 14, 2014

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Table of Contents:
1. Summary
2. Introduction
2.1. Background
2.2. Project Purpose and Scope
3. Technical Considerations
3.1. Background
3.2. Technical Information
3.2.1. Impact
3.2.2. Thermal
3.2.3. Water Resistance
3.3. Proposed Design Requirements
4. Design Considerations
4.1. Design Evolution
4.1.1. Shell Shape and Number of Cameras
4.1.2. Materials Selection
4.1.3. Attachment of Two Halves
4.1.4. Camera Mounting
4.1.5. Foam Attachment
4.2. Proposed Design
4.2.1. Shell
4.2.2. Hidden Bolt Design
4.2.3. Camera Module Design
4.2.4. Foam
4.2.5. Heat Dissipation
4.2.6. Waterproofing
4.2.7. Power Button and Charging Port
5. Results of Design Efforts
5.1. CAD Modeling
5.2. Analysis
5.2.1. Impact
5.2.2. Thermal
5.3. Prototyping
5.4. Testing
5.4.1. Impact
5.4.2. Thermal
5.5. Design Status
6. Recommendations and Proposed Efforts
6.1. Design Recommendations
6.2. Future Action Items
7. Appendix
7.1. Acknowledgements
7.2. References

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7.3. Project Budget
7.4. Gantt Chart
7.5. Current Market Offerings
7.6. Analysis
7.6.1. Thermal
7.6.2. Material Selection
7.6.2.1. Shell Material
7.6.2.2. Impact Material
7.6.3. Impact
7.6.3.1. Solidworks Simulation
7.6.3.2. Theoretical Analysis
7.7. Test Procedures
7.7.1. Drop Test
7.7.2. Thermal Test
7.7.3. Water Intrusion Test
7.8. Data Sheets
7.8.1. PureTemp™ 53
7.8.2. Battery
7.8.3. Threaded Inserts
7.8.4. Lepton™ Camera
7.8.5. 3M VHB Tape
7.8.6. Power Button
7.8.7. Gore Vent
7.8.8. PORON® 92 Extra Soft
7.9. Project Completion Requirements
7.10. Drawing Package

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1. Summary
FLIR Systems is a thermal imaging company that specializes in infrared cameras and sensor
devices for both commercial and government applications. With the release of their smallest
thermal camera to date, the Lepton™, it is now possible to create smaller scale thermal devices
than ever before. As a result, FLIR has partnered with the University of California, Santa
Barbara Mechanical and Electrical Engineering Departments to pursue an interdisciplinary
projectile thermal sensor project, the Thermal Sensor Cluster. This device is intended for use by
first responders and military personnel to remotely gather information about a hostile
environment. It will be thrown into a hazardous region, and must be able to withstand impact,
heat, dust, and water, while wirelessly transmitting visual data to a mobile device. The sensor
contains twelve thermal/visual camera pairs that are capable of capturing both still and video
footage of the surroundings.
Over the past two quarters, extensive efforts have been made to bring the Thermal Sensor Cluster
concept to fruition. The primary design concerns that have been actively addressed are impact,
manufacturability, heat dissipation, and waterproofing. The impact issue has been solved by
coating the exterior of the device with PORON® shock-absorbing foam. Additionally, the shell
of the sensor is made from impact-rated Polycarbonate. Manufacturability has been ensured
through careful CAD modeling and constant focus on the process to be used to fabricate each
component. The processes that are being designed for, such as injection molding, are too
expensive for the first functional prototype, so the final deliverable for this project will be 3D
printed. Heat dissipation for the electronics is solved by using aluminum conduction paths from
each camera to the environment, and by utilizing phase change material to ensure a steady
internal temperature. Finally, waterproofing has been addressed with a gasket, a series of O-
rings, waterproof components, and watertight glue.
The above considerations have been synthesized into a preliminary 3D printed prototype with a
shell diameter of seven inches. Testing has not yet been conducted on the prototype, as the
custom gasket is still in transit, but planned tests include a thermal test to determine the
effectiveness of the phase change material, a water intrusion test, a drop test, and an ease-of-
assembly test. Analysis presented in this report predicts the success of all of these tests.
This report only addresses the Mechanical aspects of the Thermal Sensor Cluster. All electronic
design work is being conducted by the Electrical Engineering team, and can be found in a
separate report. The expectation of the ECE team by the end of the year is that they provide
printed circuit boards for each camera assembly and for the main control board, and the battery.
This hardware will then wirelessly interface with a mobile android application that is also to be
provided by the ECE team. A significant portion of the upcoming quarter will be focused on
combining the two projects into one functional prototype.

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2. Introduction
2.1. Background
The FLIR Thermal Sensor Cluster is a projectile data collection device that uses both thermal
and visible cameras to view its surroundings. By wirelessly sending images and live video feed,
the device allows operators to panoramically view a hostile environment from a safe distance,
even if visibility is low.
The camera assembly consists of one thermal and one visible camera, both of which are housed a
fixed distance apart to allow for image meshing. FLIR’s cutting edge thermal camera being used
in the sensor cluster is called the Lepton™. The Lepton™ is a
complete long wave infrared camera module with fixed focus and is
currently the smallest thermal imaging camera available (more in
Appendix 7.8.4.). The Lepton™ uses MSX blending technology to
superimpose edges from the visible image onto the thermal image,
providing sharper visuals. Due to the Lepton’s™ dramatically
smaller size and mass than the previous standard, it is now possible
to build a projectile thermal device that is small enough to be thrown
by hand.
The competing product to the FLIR Thermal Sensor Cluster is the Eye Ball R1 throwable camera
system. Used by the Boston Police Department’s SWAT team, the Eye Ball 1 uses a self-righting
camera housing with an omnidirectional platform that can rotate 360 degrees. The Eye Ball 1
also uses a near-infrared camera with visibility up to 9 yards in environments with poor lighting.
Although this device offers many advantages to first-responders, it cannot survey the entire field
of vision simultaneously and uses poor quality thermal imaging that cannot see as far as the
Lepton™. Furthermore, environments with uneven surfaces and/or sand pose a potential problem
to its self-righting system. A more in-depth description of current market offerings is included in
Appendix 7.5.
2.2. Project Purpose and Scope
The purpose of the Thermal Sensor Cluster is to remotely gather images and video from hostile
and low-visibility environments with the use of FLIR’s thermal imaging technology. The device
is intended for first responders and military personnel and can be thrown into a potentially
hazardous environment from a safe distance, keeping the user out of harm and giving them an
advantage in dangerous situations. Once in this environment, the Thermal Sensor Cluster can
send images and live video footage in both visual and infrared wavelengths to a mobile device.
Because of its infrared cameras, the Thermal Sensor Cluster can detect potential threats or
victims in areas with poor lighting, smoke and/or fog.
Figure 1: FLIR Lepton™ camera.

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Because the Thermal Sensor Cluster may be used in stressful situations where time cannot be
spared, it must be easy to turn on and operate. It must also operate long enough for the first-
responders to survey the environment. The device must be small and light enough to be thrown
into a hostile environment from a safe distance and survive the shock from impacts with hard
surfaces. The device must also be water resistant and able to withstand heat from its internal
electronics as well as the external environment. Lastly, because the Thermal Sensor Cluster will
be mass-produced, it must be easy to manufacture and assemble.
The scope of this project is to create a functional prototype that meets all of the requirements
stated above. Together with a team of UCSB electrical engineers, the goal is to create a robust
and manufacturable enclosure that can be combined with all the necessary electronics for
transmitting visual/ infrared images and video to a mobile device. The final prototype will be
fabricated by additive manufacturing, but will be designed for large-scale molding and
machining operations (further discussed in Section 5.3).
3. Technical Considerations
The purpose of the following section is to familiarize the reader with some of the equations and
assumptions that were used to model and analyze the Thermal Sensor Cluster, and to explain
how the list of performance requirements was devised.
3.1. Background
Many performance goals of the Thermal Sensor Cluster were realized by defining the purpose
and scope of our project. In order to begin the design phase of the device, a set of performance
requirements was created. These requirements and specifications served as guidelines during the
design phase and as a standard to which the finished product could be compared.
Some of the specifications given in Section 3.3 below were created using information gathered
through benchmarking research. Because competing products were either too expensive to
purchase or still in development, benchmarking was performed through online research and
considering the features of current industry leading products. A more detailed description of this
information can be found in section 7.5 of the Appendix.
Other specifications were created using requirements defined by FLIR. These requirements
included water resistance, heat dissipation and manufacturability. Manufacturability was a
primary concern and was consistently addressed throughout the design process. The last of the
requirements were created using assumptions made during preliminary research. These
assumptions are listed in Section 3.3 and were used to fill areas of performance that were not
specified by FLIR nor found in the benchmarks created by the competitor survey.

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3.2. Technical Information
Theoretical modeling was performed on the device, both for preliminary calculations to
determine design viability, and to design components such as the gasket. These models include
thermal, impact and water resistance analyses. A short description of these models and the
governing equations is given below.
3.2.1 Thermal
The thermal analysis for the camera modules was performed using the concept of lumped
capacitance in transient heat flow. This assumes that each body involved is at a constant
temperature, meaning there is not temperature gradient each component. This method allows for
the use of a thermal resistor network as shown:
Together with the conservation of energy theorem, the resistor network allows for the
temperature of each body to be calculated over time. The conservation of energy theorem is
shown in equation (1).
(Increase in Temperature) = (Heat in) - (Heat out) + (Heat Generated) (1)
3.2.2 Impact
The analytical impact model was based on an elastic foundation model as shown in Figure 2. The
enclosure was modeled as a simple mass spring system.
Figure 2. Elastic foundation model of Thermal Sensor Cluster.
The max acceleration and the max deflection can be calculated for specified parameters as shown
in equations (2) and (3).
22
max )( nimpvga  (2)
2
22
2max
nn
imp
n
gvg
x















 (3)
where
eff
eff
n
m
k
 .

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3.2.3 Water Resistance
To waterproof the enclosure, the camera modules, camera viewing holes, power button, charging
port, and the attachment site of the two halves need to be sealed. The O-ring and Gasket were
designed based on recommended compression ratios found online at applerubber.com. The
power button and charging port are both rated to the IP67 waterproof specification (see section
5.4.3 for more information on waterproofing).
3.3.Proposed Design Requirements
Based on the scope of the project (stated in Section 2.2 above), a list of performance
specifications was developed. Some of the specifications listed were based on requirements
stated by FLIR. These requirements include water resistance, heat dissipation, and
manufacturability. Other specifications for performance were grounded in assumptions that are
stated below
Assumptions
1. The maximum vertical distance the device would be thrown is 15ft
2. The device should be no larger than 8.65in based on a size 5 soccer ball diameter
3. A throwable object of size stated above cannot weigh more than 3 lbs
4. A sufficient operating time for first-responders is 30 minutes
Table 1: Performance Specifications
Performance Specification
Impact Survives 15ft. vertical drop onto concrete.
Weight Weighs no more than 3 lbs
Size Roughly Spherical Shape with outside diameter smaller than a soccer ball
(8.65 in)
Water Resistance Survives exposure to average fire sprinkler for designated operation time of 30
minutes
Heat Dissipation Internal temperature does not exceed 55°C in a maximum 45°C environment
Manufacturability Moldable, machinable, and easily assembled
Operation Time Survives 30 minutes of use
Reusable Rechargeable, foam does not degrade, shell does not crack or deform
Easy to operate Only button on device is power button; charging port is waterproof and easily
accessible

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Figure 3: Self-right Egg
Shaped Design
Figure 3: Self-righting egg
shaped enclosure design.
Figure 4: Camera
enclosure for 24
cameras that allows
for 360˚ field of view.
4. Design Considerations
During the design of the Thermal Sensor Cluster, the most important factors that were
considered were impact, manufacturability, heat dissipation, and waterproofing.
Manufacturability was particularly important, because in the event that FLIR decides to launch
this product, it must be designed for large-scale implementation. If implemented, the device
would be fabricated by injection molding, metal casting, and machining to ensure efficient and
inexpensive production.
4.1. Design Evolution
The Thermal Sensor Cluster has undergone many iterations in the design process. These
iterations include:
1-Number of cameras modules
2-Shell shape
3-Material used for camera modules
4-Material used for shell
5-Attachment method of two halves
6-Mounting of camera modules
7-Attachment of impact-resistant Foam
4.1.1. Shell Shape and Number of Cameras
The current design has evolved from numerous SolidWorks
iterations, and a scaling back of the design requirements for the
final project. Initially, FLIR required a full panoramic view of
the device’s surroundings. In an attempt to reduce the required
number of cameras, an egg shaped self-righting design shown in
Figure 3 was drafted. This design allows for 360 degree viewing
using only 10 cameras, but it is possible that in environments
with a soft or non-flat surface the device will be unable to right
itself. The orientation of the cameras makes it imperative that the device settles in an upright
orientation in order to obtain useful information. The enclosure needs to function in all
conditions therefore the risk that the self-righting feature would fail was too significant, so an
enclosure with more cameras was designed.
Through a process of geometric analysis and 3D modeling, it was
determined that at least 24 cameras are necessary to capture a panoramic
view, as dictated by the 60˚ field of view of each camera. Based on that
design consideration, a new enclosure was modeled that had 24 evenly
spaced faces. The 24-sided enclosure shown in Figure 4 was seen as the
best design at the end of Fall quarter. Early this quarter the ECE team
indicated that each camera needed a circuit board that was 1.3 in by 1.3
in. The circuit boards mount to the cameras which are attached to the

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Figure 6: Camera enclosure with angled edges
along which the gasket must seal.
Figure 5: Camera enclosure that cannot be
injection molded.
surface of the enclosure. Through SolidWorks modeling of the 24 circuit boards inside of the
enclosure, it was determined that the size of the enclosure would need to be about the size of a
basketball to fit all the circuit boards. This size would make the enclosure too heavy and
impractical for use by first responders or the military. At this point it was indicated by FLIR that
a reduction to 12 cameras was acceptable, even though a
full panoramic view was not possible. Furthermore,
FLIR is working on expanding the field of view of their
cameras, so a 12 camera enclosure may provide 360
degree in the future.
Once the number of cameras was established, the shape
of the enclosure had to be determined with assembly and
manufacturability in mind. Originally a flat-faced
dodecahedron shape was modeled because the flat
surfaces allow for easy camera attachment. Problems
arose with the manufacturability of this design,
however. For the dodecahedron to be cut in half and
have a flat surface for the gasket seal, faces would need
to be cut in half as shown in Figure 5. As can be seen in Figure 5, the labeled overhanging face
makes casting this design impossible because it will prevent the plastic from being pulled out of
the mold.
To solve this issue a dodecahedron that did
not have a flat surface for the gasket seal
was modeled in Figure 6. This design
could be easily cast, but it causes the
gasket seal to be on angled surfaces, which
is very difficult to waterproof due to
tolerance issues. Intolerance causes the
gasket seal to have regions of high and
low stress concentrations, and water leaks
through the regions of low stress.
From these design iterations, it was
decided that the enclosure had to be modeled as a sphere with flat surfaces on the inside for
mounting of the camera modules. A spherical design shown in Figure 7 is both easy to cast and
has a flat surface for the gasket seal. This design also eliminates the corners of the dodecahedron
shape that have high stress concentrations on impact. (Refer to Appendix 7.6.3.1.). The only
downside of this design is that the sphere will not come to a stop naturally like the dodecahedron
shape. This issue will be fixed by cutting and attaching the foam in a geometric pattern that

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Figure 7: Finalized spherical shell design that is moldable and can be waterproofed easily.
results in flat surfaces on the enclosure to encourage stopping. The foam will be discussed more
in Section 4.1.5.
4.1.2. Materials Selection
Shell
Possible materials were determined using Granta’s CES selection software. Performance indices
were based on maximizing strength and fracture toughness while minimizing mass. According to
the material plot shown in Figure 2 of Appendix 7.6.2.1 the best performing materials were
CFRP, PC, Nylon, and PEEK. A summary of their material properties is shown in Table 2
below. Due to its poor machinability, high cost, and high stiffness, CFRP was eliminated.
Although PEEK showed slightly better performance over Nylon and Polycarbonate, it was
eliminated due to its high cost. Of the remaining materials, Nylon was the best performer with
Polycarbonate as a close second. A more thorough explanation of the material selection process
is described in Appendix 7.6.2.1.
Table 2: Material Property Summary
Material CFRP Polycarbonate Nylon PEEK
Density (lb/ft^3) 93.6-99.9 71.2-75.5 69.9-71.2 81.2-82.4
Price USD/lb 17-18.9 1.86-2.05 2.06-2.26 45-49.5
Young’s Modulus Mpsi 10-21.8 0.29-0.354 0.38-0.464 0.544-0.573
Yield Strength ksi 79.8-152 8.56-10.2 7.25-13.7 9.43-13.8
Fatigue Strength 10^7 ksi 21.8-43.5 3.21-4.47 5.22-9.57 4.08-5.98
Fracture Toughness ksi.in^0.5 5.57-18.2 1.91-4.19 2.02-5.11 2.49-3.91
Mechanical loss coeff (tan delta) 0.0014-0.0033 0.0164-0.0181 0.0125-0.0153 0.0101-0.0106
Max Service Temp F 284-428 214-291 230-284 462-500
Min Service Temp F -190 - -99.7 -190 - -99.7 -190 - -99.7 -190 - -99.7
Machinability 1-3 3-4 3-4 3-4
Moldability 4-5 4-5 4-5 4-5

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Since the prototype will be 3D printed, a comparison of prices between 3D printing
manufacturers was completed, and it was found that the company Quickparts® had the cheapest
costs. The properties of materials vary significantly with the way they are manufactured, and it
was found that 3D printing reduced the tensile strength, toughness, and impact resistance. As
described above, Nylon was determined to have the best properties for a robust impact resistant
structure, but the 3D printed Nylon showed lower impact resistance and tensile strength than
polycarbonate. Quickparts® will cast Nylon with a high Tensile Strength, but this process
requires a polyurethane mold to first be 3D printed. Unfortunately the initial cost to make the
polyurethane mold is over $3,000, making this process too expensive. Table 3 shows the material
information vs. cost for the materials at Quickparts® that best suit the shell. It was thus decided
that polycarbonate will be used for the final prototype. It should be noted that this is only for the
3D printed prototype stage. If the design goes forward, nylon will be revisited as a possible
material.
Table 3: Material properties and price quotes from Quickparts®
Tensile
Strength
(psi)
Izod Impact (ft-
lb)/in
Density
(kg/m^3)
Cost of
Printing
ABS 3200 2 1020 $1,104.00
Polycarbonate 7600 1 1190 $1,214.00
Nylons Polyurethane Cast 9,740 0.78 1150 $4,858.00
Nylon (SLS) 6,237 0.6 1150 $1,438.00
Impact Material
Preliminary selection of impact materials was done using Granta CES selection software.
Possible foams and elastomers were determined based on a stiffness range determined from the
preliminary impact analysis (see Figures 2 and 4 of Appendix 7.6.2.2.). After further narrowing
materials down using performance indices (see Appendix 7.6.2.2.), and researching individual
materials to determine their practicality as impact absorbing materials, it was determined that
Polyurethane, Polyethylene, and Neoprene foam are materials that are commonly used for impact
absorption. In addition to these materials Sorbothane, Silicone Foam, and Santoprene were other
materials that were found to be common impact absorbers. These materials were compared in a
drop test (See Section 5.4.1 and Appendix 7.7.1.) The results of which showed that PORON®, a
type of polyurethane, was the best performer based on energy absorption. It was decided to go
forward and explore different types of PORON® to be used as the impact absorbing material.
4.1.3. Joining of Two Halves
Three designs were considered with regards to joining the two halves of the device: clamps,
external bolts, and hidden bolts. The implications of each design are detailed below.

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Clamp – The clamp design features two C-shaped brackets with grooves on
the insides. The two halves of the shell have lips at their bases that slide into
the grooves of the clamps, and the clamps are fastened together with hex
screws. Originally, the clamp design seemed most desirable for its uniform
pressure distribution, ease of use, and its allowance for internal feature
modifications. However, the external geometry of the clamps introduces
sites of high principle stress. Additionally, the clamps would be difficult to
pad properly to maintain a uniform shock absorbing layer throughout the
entire exterior of the device.
External Bolts – The external bolt design features five lips distributed
evenly along the base of each half of the shell. The lips are screwed
together with hex screws. This design was beneficial because the screws
did not introduce any external geometry (would not make contact with
ground). However, the lips, similar to the clamps, offered sites of high
stress concentration, and would be difficult to pad evenly.
Hidden Bolts – It was decided that the hidden bolt design would be
implemented in the final product. The geometry of the feature is entirely
concealed except for a small counter bore into which a hex screw is
dropped. The advantages of the hidden bolt design are easy padding, easy
O-ring placement for waterproofing, and no external stress concentrators.
The disadvantage of this design is that the internal extruded geometry
required to support the screws limits the area in which the camera PCBs
can be placed.
4.1.4. Camera Mounting
Two different design options were considered with regards to
mounting the camera modules to the shell. The first option (Figure
11) was to glue the modules’ PCBs directly to interior ribs,
orienting them toward large window cavities in the shell. The
second option (Figure 12) was to assemble individual metal camera
cap subassemblies to be inserted into large openings in the shell
from the outside.
Figure 9: External bolts.
Figure 8: Clamp design.
Figure 10: Hidden bolts.
Figure 11: Ribbed board mount.

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Although the rib mounting would be a quick and easy method of mounting the camera modules,
this design introduces several issues. Primarily, the camera modules and PCBs would be very
difficult to access for maintenance and adjustment as they are glued, face down, to the interior
surface of the shell. Additionally, the tolerances required to properly orient the camera toward
the shell opening would be entirely dependent on the outcome of the shell manufacturing; if the
shell doesn’t meet these strict tolerances, there is not a robust method of adjusting the orientation
of the cameras.
The camera subassembly design addresses both of these issues.
After the metal caps are glued down to the shell and water-
sealed, the camera module and PCB can still easily be removed
for maintenance and adjustment as they are screwed in place
rather than glued in place. The camera module and PCB can
easily be replaced in their previous orientation after removal.
The tolerances are also much less dependent on the
manufacturing of the shell with this arrangement; the camera
module can easily be tilted by adding spacers or washers
between the camera cap standoffs and the base of the PCB to
achieve the desired orientation. It is for these reasons that it was
decided to proceed with the camera subassembly design.
However, there are some design challenges with the camera subassembly that must be overcome.
The camera caps, being made of metal, add a significant amount of weight to the payload.
Furthermore, there is a considerable amount of machining hours and material cost required to
manufacture the caps. These issues are addressed in Section 4.2.3 along with a thorough
description of the design considerations associated with the development of the camera
subassembly.
4.1.5. Foam Attachment
In order to address shock absorption, the shell will be covered in a layer
of impact foam. The attachment of this foam was an important design
consideration because it must be durable and easily manufacturable. The
two attachment options that were considered were a T-channel system
and adhesive mounting as shown in Figure 13. The T-channel offers
superior durability, however, it requires grooves in the shell and
extrusions on the foam that are difficult and impractical to fabricate.
Adhesive presents the possibility of peeling, but the ease of
manufacturing and the high strength of industrial adhesives render it the
more desirable option. Further details about the impact foam will be
discussed in Section 4.2.4.
Figure 13: T-channel (top)
and 3M VHB tape (bottom)
Figure 12: Modular design

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4.2. Proposed Design
4.2.1. Shell
The finalized design is shown in Figure 14, and it
represents design efforts to create a product that
both meets the design specifications and can be
easily manufactured. As discussed in Section 4.1.1,
the enclosure will be injection molded in two halves
with 6 evenly spaced cameras on each half. The
enclosure needs to be injection molded because
injection molding will reduce the costs of
manufacturing and the amount of post machining.
Due to the requirement that the enclosure must
transmit WIFI data, it was determined that metal
couldn’t be used as the enclosure material because it
would create a faraday cage. A materials selection
process was done, and it was found that cast nylon provides the best strength to weight ratio as
was discussed in Section 4.1.2. Unfortunately 3D printed nylon has weaker material properties
than cast nylon and 3D printed polycarbonate ( Section 4.1.2.). Because of this, the enclosure to
be presented at the end of the year will use polycarbonate, but future prototypes will be made of
cast nylon.
Post machining will require a five-axis mill because the holes for the camera module assembly
cannot be molded. The shell will be molded with internal sacrificial geometry that can be held in
a vice during machining. After the camera module extrusions have been created, the power
button and charging port will be installed. The enclosure is designed so that the cameras modules
can be assembled independently of the enclosure. This will reduce production time, and it will
allow for the camera modules to be tested prior to installation. The completed camera module
assemblies will then be installed onto the enclosure from the outside. Installing the camera
modules from the outside instead of the inside will make assembly easier because it prevents
workers from working in the confined space of the enclosure.
4.2.2 Hidden Bolt Design
As discussed in Section 4.1.3, the two halves of the
shell are to be joined with hidden bolts. Interior
standoff lips support the screw geometry on both
halves of the shell (Figure 15, left). The bottom half of
the shell features blind holes into which E-Z LOK
threaded inserts (see Appendix 7.8.3.) are press-fitted
(Figure 15, right). The top half of the shell features
counter bores to accommodate for hex screws (Figure
15). The two halves are screwed together evenly with a
Figure 15: Hidden Bolt Design with E-Z LOK insert
Figure 14: Finalized Enclosure Design

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torsion screwdriver to ensure equal pressure throughout the gasket.
The purpose of this design is to minimize the exposed fastener geometry, allowing for maximum
padding coverage, as well as eliminating potential sites of concentrated stress. Hex screws are
used because they are durable and can be fastened with an allen wrench in a pinch. The E-Z
LOK threaded inserts were used to eliminate the need for a second tool to join the two halves of
the shell.
4.2.3. Camera Subassembly Design
As discussed in Section 4.1.4, it was decided that the camera
modules would be mounted to the shell via a camera
subassembly design. Camera caps plug 12 counter bores
arrayed evenly over the external surface of the shell. The
design requires that the camera module lenses line up with the
holes in the camera cap, and these holes must be large enough
to allow for the full field of view offered by the Lepton™. A
silicon window covers the Lepton™ camera hole, and a glass
window covers the visible camera hole. These windows are
glued to window fixtures, which are then glued to the inside
of the camera cap (the gluing and waterproofing of the
windows and caps are detailed in Section 4.2.6). The camera
module is mounted to the PCB, and the PCB is screwed into
four standoffs on the camera cap. Figure 16 shows an
exploded view of the camera subassebmbly and figure 17
shows a transparent view.
In designing the camera cap, four factors were taken into
consideration: heat transfer, mass, durability, and
manufacturability. The cap needs to act as a heat path from the
inside of the device to the ambient air, as the majority of the
device is made of polycarbonate, an
insulator. Therefore, it was decided that
the caps be made of a (preferably
lightweight) metal. The metal must be
able to withstand abrasive and corrosive
environments after repeated use. Lastly,
the cap geometry and material must
allow for affordable, quick, and basic
manufacturing. Figures 18 shows a
rendering of the cap.
Figure 16: Exploded view of
camera subassembly
Figure 17: Transparent view of
camera subassembly
Figure 18: Camera cap

17
The two materials that were immediately under consideration were aluminum and magnesium.
While magnesium alloys are marginally better heat conductors, less dense, and tougher than
most aluminum alloys, the manufacturability and cost of aluminum is considerably more
appealing. Therefore, 6061 aluminum is the material of choice. It can easily be machined in-
house and is very common stock material. Furthermore, 6061 aluminum is corrosion-proof even
after abrasion and therefore does not need to be coated or treated in any way.
The caps are machined from 2” round stock 6061 aluminum. The stock is faced and the outer
diameters are cut with a grooving tool on a manual lathe. The stock is cut down to size on a
horizontal band saw and loaded face-down on angled jaws in a CNC mill. The remaining
geometry is cut with only 3 tools and 2 tool changes. Finally, the PCB standoffs are hand-tapped.
A detailed drawing and manufacturing procedure for the camera cap is included in Appendix
7.10.
4.2.4. Foam
As mentioned in section 4.1.5, adhesive was chosen as the
attachment method for the shock absorbing foam. To
determine which foam to use, drop tests were performed
on various foams and rubbers and the rebound height after
impact was recorded. From this, the energy absorption of
each material was calculated, and Rogers Corporation
PORON® Microcellular Urethane was found to have the
highest energy absorption. More information on the drop
test can be found in Section 5.4.1. The configuration of
foam panels on the shell is shown in Figure 19. This
configuration was chosen in lieu of a full coverage design
because a large sheet of PORON® stretched over a curved
surface would result in creases and bubbles. The small
pieces reduce this issue and also simply the peel-and-stick
process for the assembly worker.
The adhesive chosen to attach the PORON® to the shell is 3M® VHB Tape. This adhesive can
be applied directly onto the PORON® by the manufacturer, allowing for easy peel and press
attachment. VHB Tape creates an extremely strong, permanent bond that is ideal for the Thermal
Sensor Cluster. More information about PORON® and VHB Tape can be found in Appendix
7.8, Sections 8 and 5 respectively.
4.2.5. Heat Dissipation
Heat dissipation is an important concern for the Thermal Sensor Cluster because the ideal
operating temperature for the Lepton™ camera is under 55˚C. Though the device is being
designed for a maximum of 45˚C ambient temperature, options were explored for increasing this
Figure 19: Full assembly showing the
configuration of PORON® on the
shell

18
constraint. An ambient temperature of 45˚C allows for heat sinking to the environment, however,
if higher operating temperatures are desired, heat dissipation
will need to be addressed differently. The idea of active
cooling was briefly explored but discarded early on in the
design process because it adds significant complexity and
weight to the design. Alternatively, since the cluster will
only be deployed for a maximum of thirty minutes at a time,
phase change materials were found to be a perfect passive
heat dissipation solution.
Phase change material (PCM) is a material designed to melt at
a certain temperature and absorb heat for the phase change
reaction as shown in Figure 20 (top). The material that was
chosen is PureTemp™ 53, which melts at 53˚C and absorbs
225 J/g. More information about this material is given in
Appendix 7.8.1. The advantage of PCM is that it can be
attached to any heat source inside the device to absorb a finite
amount of energy depending on the mass that is utilized. The
analysis to determine the necessary quantity of PCM is given
in Appendix 7.6.1. PCM is compatible with both design
options: the 45˚C constraint and higher operation
temperatures. When designing for 45˚C, the external caps
covering the camera assembly are made of aluminum to allow heat to flow to the environment.
When designing for operating temperatures above 55˚C, the camera caps are made of
polycarbonate to insulate the internal electronics from the outside heat. This means that the PCM
will solely absorb all the heat produced by the electronics, along with all heat that is conducted
from the environment.
The encasing needs to be water resistant so that if it is thrown into an
environment with water such as a burning building with sprinklers on,
it can still function. FLIR has indicated that the encasing only needs
to be water resistant, but with the current design it will be fully
submersible. The water resistance of the performance specification is
that the encasing must survive a sprinkler test for 30 min. To meet
this specification all possible entrance points for water must be
eliminated. The water entrance points that have been waterproofed
are the camera module holes, the seal between the two shell halves,
viewing holes for the cameras, charging port, power button, and
GORE Vent.
Figure 20: Heat vs. Temperature plot
for PureTemp™ 53 (top) and samples
of PureTemp™ 53 (bottom).
Figure 21: The camera module will be
waterproofed with both an O-ring seal
and lens hole covers.

19
Figure 22: Gasket seal.
The camera modules will be waterproofed with an O-ring piston seal between the camera module
and the shell (See Figure 21). The O-ring is shown in green surrounding the camera module. The
O-ring seal will be made with a 1.5in Buna-N O-ring, and its design meets the recommended
guidelines for a piston O-ring seals. It will have 3% stretch (1-5% recommended), 32%
compression (10-40% recommended), 85% gland fill (80-90% recommended), and 32% squeeze
(10-40% recommended). See Appendix 7.6.4 for calculations. The extrusion gap between the
piston and the bore is .015in, and this will translate to a snug fit between the camera module and
the enclosure. This snug fit is desired so that friction can hold the camera module in place while
it is being glued to the enclosure.
A gasket seal instead of an O-ring was used to
waterproof the attachment between the top and
bottom of the enclosure. Based on FLIR’s
recommendations, extrusions on the plastic were
designed so that the enclosure can be tightened down
until the plastic on the top enclosure hits the plastic
on the bottom enclosure. This is preferable to having
the plastic seal onto the gasket because vibrations
will cause the screws holding the enclosure together
to come loose if there isn’t plastic touching plastic
(See Figure 22). Gasket seals are recommended to
have between 10-50% compression, so the enclosure is designed to have 20% compression on
the entire surface. A ridge can be seen in Figure 22 that brings the compression along it up to
50%. Because the screws will need to compress the gasket they will need to put 82lb of force per
screw onto the enclosure.
The viewing holes for the thermal and visible cameras also need to be waterproofed as seen in
Figure 21. These holes need to be individually waterproofed because the thermal cameras cannot
“see” through glass. The thermal camera therefore needs its own silicon wafer in front of it. The
silicon wafer and glass window will be installed with waterproof glue on the inside of the camera
module (shown in pink in Figure 21). Waterproof testing will be performed on each camera
module to ensure that the glue has fully surrounded and waterproofed the viewing holes.
The power button and the charging port selected for the encasing were
both rated as waterproof sealing by specification IP67. IP67 is a
waterproof rating that means the product can withstand immersion to
between 15 cm and 1 m. This spec exceeds the performance
requirements for our enclosure. Once the power button and the
charging port have been installed a waterproofing test will be
conducted.
Lastly, a GORE-Vent has been added to the encasing to relieve
pressure build-up. Difference in temperature between the inside of
Figure 23: Size of the
adhesive GORE Vent.

20
the encasing and its surroundings will cause pressure differences. Pressure differences are known
to stress gasket seals and over time, reduce their impermeability. GORE-Vents solve this issue
because they are permeable to air but not to water. The GORE-Vent is made of the same Teflon
liner that is used to waterproof jackets. There are many different GORE-Vent types, but the one
to be used for this encasing is an adhesive pad that will be stuck to a hole in the encasing. See
Figure 23. Like the charging port and power button, the GORE Vent is also rated for the
specification IP67. See Appendix 7.8.7 for the spec sheet of the GORE Vent.
4.2.7. Power Button and Charging Port
The power button and charging port (Figure 24) are easily accessible on the top half of the shell,
where the main PCB is mounted. The power button is a 14mm Harsh Environment Push-Button
Switch from McMaster-Carr (see Appendix 7.8.6.). The button is sealed for protection from
moisture, debris, and temporary water submersion. A protective casing prevents the button from
being pressed upon impact and is glued into a cavity in the power panel.
The charging port is an Amphenol LTW Mini USB B connector (see Appendix 7.10). The port
has an IP67 waterproof rating within a temperature range of temperatures from -20°C to 70°C.
The housing of the port is inserted into a cavity in the power panel. A rubber stopper plugs into
the mini USB port when not in use to prevent water leakage.
The wired ends of the power button and charging port are located close to the main PCB to aid in
cable management (Figure 24).
Figure 24:
Exterior view of
power panel
(left) and interior
view of power
panel (right)

21
5. Results of Design Efforts
5.1. CAD Modeling
The CAD modeling efforts were explained in detail in Section 4, and will not be repeated here.
As explained in Section 4, great emphasis was placed on ensuring the manufacturability and
efficient assembly of the device, as well as the scalability of the CAD model for flexibility with
ECE Team dimensions. Additionally, the drawing package in Appendix 7.10 shows the drawing
view of each individual component that was modeled.
5.2. Analysis
5.2.1. Impact
In order to ensure structural integrity of the enclosure impact analysis was supplemented by drop
testing discussed in section 5.4.1. The impact analysis was done both analytically and
computationally using SolidWorks Simulations.
The SolidWorks Simulations were performed to determine which material would provide the
best strength to weight ratio for the enclosure. The enclosure was dropped from a height of 20 ft
onto a surface without any damping or energy absorption to simulate the enclosure falling on
cement. Multiple simulations of the enclosure landing on different angles were performed to
determine the worst case landing angle. It was found that the highest stresses and deflections
would result when the enclosure landed on the face containing the charging point and power
button. Therefore this enclosure orientation was used for all future tests and comparisons
between materials. The enclosure material was varied between ABS, Polycarbonate, and Nylon
for the simulations. The results of the simulations are shown in Table 4 below, and the
SolidWorks stress analysis can be seen in Appendix 7.6.3.1.
Table 4: Max Stress and Displacement for shell materials dropped from 20ft.
Material
Max Stress (MPa)
Max Displacement
(mm)
Abs 72.8 1.94
Nylon 38.7 1.992
Polycarbonate 88.4 1.939
From this simulation nylon is shown to have the smallest max stress compared to ABS and
Polycarbonate, but it also has the highest displacement. Nylon will have 2.28 times less stress on
impact than polycarbonate, but polycarbonate’s tensile strength is just 1.22 times stronger. This
suggests that despite its inferior tensile strength, nylon is a better material to use for impact
absorption than polycarbonate or ABS.
Analytical analysis was done in order to predict the impulse response of the device as it hits the
ground. This information was used in order to narrow down the selection of impact materials and

22
to predict the stresses within the shell. This section includes a summary of the analysis. For a
more detailed explanation see the analysis report in Appendix 7.6.3.2.
The analytical model was based on a simple elastic foundation model as shown in Figure 25.
Since the dampening coefficient of materials is not readily available, the system was modeled as
a simple mass spring system. From this the max acceleration and the max deflection can be
calculated for specified parameters as shown in equations 2 and 3.
22
max )( nimpvga  (2)
2
22
2max
nn
imp
n
gvg
x















 (3)
where
eff
eff
n
m
k
 .
By setting values for mass, geometry, and impact velocity, an ideal material stiffness can be
determined such that the material fully compresses for those parameters, thus extending the time
at which the impulse is felt, which reduces max acceleration. Different values for Young’s
modulus as well as max acceleration were determined for a range of values as shown in Figures
2a-c of the impact report in Appendix 7.6.3.2.. This information was used in order to narrow
down materials for impact as discussed in Section 4.1.2.
Stress in the shell material was estimated using Hertz mechanics as discussed in the
supplemental report [appendix #]. Failure was based on the von Mises failure criterion and is
expressed by equations (4), (5), and (6).
(4)
(5)
      2
31
2
32
2
21
2
1
 v (6)

23
The impact analysis was done both analytically using the von Mises failure criterion and
computationally using SolidWorks Simulations. The enclosure was dropped from a height of 20
ft onto a surface without any damping or energy absorption to simulate the enclosure falling on
cement. Multiple simulations of the enclosure landing on different angles were preformed to
determine the worst case landing angle. It was found that the highest stresses and deflections
would result when the enclosure landed on the face containing the charging point and power
button. Therefore this enclosure orientation was used for all future tests and comparisons
between materials. The enclosure material was varied between ABS, Polycarbonate, and Nylon
for the simulations. The results of the simulations are shown in Table 5, and the SolidWorks
stress analysis can be seen in Appendix 7.6.3.1.
Table 5:Solidworks Simulation Drop Test Data
Material Young’s
Modulus
(GPa)
Poisson’s
Ratio
[Mpa] Max Stress
SolidWorks
(MPa)
Max Stress
Analytical
(MPa)
%Error
ABS 1.2 0.394 18.5-51.0 72.8 99.0 26.5
Polycarbonate 2.3 0.39 59.0-70.3 88.4 173.6 49.1
Nylon 1.6 0.3 50.0-94.5 38.7 106.2 63.6
The results showed a slight disagreement between the analytical model and the finite model. This
however was expected due to the large assumptions that had to be made for the analytical model.
The results show some agreement, which indicates that the values are at least on the right order
of magnitude. According to the Solidworks simulation, nylon had the least amount of stress.
Furthermore, the analysis predicts that the enclosure could possibly survive a drop from that
height without the use of impact absorbing materials. With the addition of an impact material
layer it will be expected that the stresses decrease significantly.
5.2.2. Thermal
As addressed in Section 4.2.5, there are two heat dissipation paths in the design under a 45˚C
ambient temperature constraint. The first is the phase change material that will absorb the
electrical energy produced by the main circuit board. The second is the aluminum camera cap
that conducts heat from the camera board to the surface of the shell, and then dissipates it by
Figure 25: Winkler elastic foundation model for impact material. Here
shear between adjacent elements is ignored.

24
convection to the environment. The analysis in Appendix 7.6.1 contains calculations for the
feasibility of this solution. It was found that in the worst case main board heat generation case of
5 W given by the ECE team, only 0.176 pounds of phase change material are needed for a 30
minute exposure. Additionally, Figure 26 shows the transient temperature responses of the
camera, the circuit board copper plate, and the aluminum camera cap assuming 150 mW
generation by the camera and 45˚C ambient temperature.
The waterproofing analysis consisted of calculations to determine the gasket compression and O-
ring squeeze, compression, stretch and glandfill. Refer to 4.2.6 for the results of these
calculations and Appendix 7.6.4 showing how the calculations were done.
To compress the gasket large amounts of force (410lbf) will need to be applied by the screws.
The force that the screws need to apply will transfer to the plastic enclosure therefore a stress
simulation was completed to determine if the stress on the enclosure would be significant. The
max deflection of the enclosure was .087 mm and the stress was 15.5 MPa (See Figure 27 and
28). These values are well within the allowable stresses and deflections of the enclosure.
Figure 27: Shows the deflection of the
enclosure do to the force exerted by
the screws. Note SolidWorks has
greatly exaggerated the deflection.
Figure 26 :
Temperature vs.
Time Plot for
Camera Module

25
5.3. Prototyping
As stated in the Section 2.2, the end goal of the project is a functional prototype. Specifically, the
prototype should meet the physical requirements and withstand the applied conditions detailed in
Section 3.3. However, the prototype is not required to be fabricated from finalized materials and
manufacturing techniques and may not include all of the exact interior components. The testing
will be performed on two prototype revisions; the final revision will be fabricated once the
current revision demonstrates sufficient performance based on the performance specifications. A
comparison of the features of each prototype revision is detailed in Table 6.
Table 6: Prototype Comparison
Current Revision Final Revision
Shell material ABS (3D print) Polycarbonate (3D print)
Shell Size 7 in diameter 6 in diameter
Camera cap windows Simulate by sealing window
openings for water test
Glue finalized windows for water
test
Shock-absorbing
material
Drop test onto stock material
Cut and mounted to shell for drop
test
Interior components Simulated mass Actual electrical components
Peripheral components such as the camera caps, power button, charging port, and fasteners were
designed and selected to accommodate for the ± 0.010 inch tolerance of 3D prints. The camera
caps feature some limit tolerances associated with waterproofing and camera lens alignment (see
Appendix 7.10). The power button and charging port will still function as designed assuming the
shell prints within tolerance. The fastener geometry, although designed to accommodate the
fasteners at zero tolerance, can be post-machined to meet the intended dimensions.
Figure 28: Shows the Stress in the
enclosure do to the force exerted
by the screws.

26
While the tolerances for 3D printing are relatively poor, the tolerances of casting, the future
intended manufacturing technique (see Section 4.), are significantly tighter. Therefore, meeting
the performance requirements with a 3D printed prototype demonstrates confidence in the
performance of a cast prototype.
5.4. Testing
5.4.1.Impact
An impact test was performed in order to quantitatively determine the best impact absorbing
material for this device. Two key parameters examined in the test were the max acceleration that
the drop sample underwent as well as the amount of energy absorbed by the material. The
acceleration of the drop subject was determined using an Arduino microcontroller to record the
output from a ±200g accelerometer. The energy absorption of the material was calculated from
the initial drop height and the corresponding rebound height by using conservation of energy as
shown in equation (7). The heights were determined using a tape measure and a video camera.
Since a prototype had not yet been made at the time of testing, the drop subject used was a
hemispherical shell that was similar in weight and size to the design (see Figure 1 of Appendix
7.7.1.).
( ) (7)
The accelerometer results from the testing
were insubstantial due to limitations in the
sampling rate of the Arduino microcontroller
as well as the peaking of the accelerometer at
low heights. Accelerations could only be
measured for very low drops (see Figure 29),
and for most materials the sampling rate was
not high enough to get an accurate profile of
the acceleration peak. It was thus not possible
to access the materials at the intended max
drop heights. The test was not a total failure,
however, since the energy absorption of the
different materials was still determined. The
results of these calculations are shown in
Figure 30. From this information it was
determined that PORON® was the best
performer in terms of energy absorption. For
future tests different samples of PORON®
Figure 29: Acceleration data for Polyethylene/
Polyurethane hybrid foam at various heights.
Accelerometer is shown to peak out at around 4-
5 feet.

27
will be assessed using high-g accelerometers and a data acquisition device provided by FLIR’s
vibration lab.
5.4.2. Thermal
Thermal testing has not yet been conducted, but a testing procedure has been written and can be
found in Appendix 7.7.2. The goal of the thermal test is to determine if the phase change material
can effectively regulate the interior temperature of the enclosure for thirty minutes while the
ambient temperature is 45˚C. This test will be performed as soon as the preliminary prototype is
complete.
0
10
20
30
40
50
60
70
80
90
100
% Energy
Material
Impact Energy Absorbed
Figure 30: Energy Absorption data for various materials from drop tests.

28
5.4.3.Waterproofing
A waterproof test was completed on the O-ring seal that surrounds the camera module. FLIR
requested that the enclosure be able to withstand fire sprinklers for 30 min, but the enclosure was
tested to make sure that it exceeds this parameter (See Test Procedure in Appendix 7.7.3). The
camera module was submerged in water 1 in deep
for 30 min and paper towels were placed along the
camera module to determine if any water had gone
through.
When the camera modules were placed in the
enclosure, it could be seen that the O-ring was not
fitting into the enclosure properly. The O-ring was
preventing the camera module from being flush
with the outside of the enclosure despite the bore
hole being oversized. See Figure 31 for further explanation. Because the O-ring would not fit
into the bore hole, the seal leaked
immediately when it was tested with water.
Trevor Marks was consulted and a solution
was devised to fix this issue and can be seen
in Figure 32. The camera module was
remade, and the O-ring groove was lowered
from the surface so that it could fit into the
bore even with intolerance. The remade
camera module didn’t let any water in when
tested with 1in deep water for 30 min. An
image of the testing can be seen in Figure 33.
Only one of the caps had been made, so the water
level could only be tested at a depth of 1in, but future
tests will involve deeper water immersions.
Only the O-ring seal has been tested at this point
because the company (Sealing Solutions) that is
cutting the gasket has been slow to ship the designed
gasket. A shipping conformation has finally been
received and the gasket should arrive in the next week.
Once the gasket has arrived the same test as above
will be repeated to ensure waterproofing of that seals.
Figure 31: The original O-ring design
with the O-ring not fully inserted into the
bore causing leaks.
Figure 32: The improved O-ring design with the
O-ring fully inserted into the bore.
Figure 33: 1in deep water immersion test
with colored water for visibility.

29
5.5. Design Status
Analysis of the three major considerations of impact, heat dissipation, and waterproofing has
resulted in significant confidence in the success of the design. Additionally, CAD review by
FLIR’s engineering staff has confirmed the manufacturability of the shell and the ease of
assembly of the components.
Recent prototyping efforts were made to create an ABS shell and aluminum camera caps, while a
custom order has been placed for the waterproofing gasket. Once the gasket arrives, thermal and
waterproofing tests can commence, and analysis shows that they will be successful. In the
interest of preserving the prototype, no drop tests have been performed with it so far, as there is
no room in the budget in the event of impact damage. However, drop tests with a cheap,
hemispherical test subject have determined that the shock-absorbing PORON® foam dissipates
90% of impact energy, which provides confidence in the success of eventual drop tests.
Once the tests have verified the performance requirements, the shell will be reprinted in
polycarbonate and all tests will be repeated to demonstrate the success of the functional
prototype.
6. Recommendations and Proposed Efforts
6.1. Design Recommendations
A number of revisions were made to the project completion requirements over the course of the
quarter, mostly related to changes in the design. The updated project completion requirements
are listed in Appendix 7.9. The first change is that the drop height for verifying the impact
damping of the device was reduced from 20ft to 15ft. This criterion is set by anticipating the
largest drop that would be experienced by the device in the field, and 20ft was deemed
unnecessary. The cluster will mostly be thrown through doorways over short distances and close
to ground level. The largest drop that is being designed for is an inaccurate throw into a second
story window, which will result in the device falling straight down from roughly 15ft onto
concrete as a worst case scenario.
The second change is a slight decrease in maximum outer diameter. This was made possible by
the reduction in size of the ECE team’s camera circuit board. The new 8 inch outer diameter
specification includes the thickness of the impact foam.
Additionally, the percent of panoramic coverage has changed this quarter due to a reduction in
the number of cameras on the device. With only twelve cameras, each with roughly a 60˚ field of
view, the coverage will not be as complete as was initially expected with twenty-four cameras.
This design decision was made in anticipation of future wider angle thermal cameras being
available in the future.

30
Finally, the written user manual was replaced by an informative video. This video will
effectively convey the same information as the user manual, but in a more interactive and
concise format. Special emphasis will be placed on safety considerations concerning both the
user of the device as well as anyone else in the deployment zone.
6.2. Future Action Items
As discussed in section 5.5, a prototype is almost complete and will be used to perform
verification tests. The action items for the next quarter are as follows. Appendix 7.4 shows the
Gantt chart for the project and gives completion dates for the tasks below.
1. Finish prototype
a. Finish fabricating camera caps
b. Tap holes
c. Obtain gasket
d. Attach power button and charging port
2. Analyze tolerances on shell and caps
3. Thermal test
a. Using FLIR’s thermal chamber to test interior temperature when phase change
material is present
4. Water intrusion test
a. Thirty minute sprinkler exposure once all waterproofing measures have been
implemented (i.e. gasket, O-rings, etc.)
5. Drop test
a. Using FLIR’s drop test station and 1000 g accelerometer
b. This will be done with the most effective foam combination based on prior drop
tests
6. Camera module assembly test
a. Test easy of assembly of the camera module with actual camera fixture and circuit
board
7. Receive final circuit board specifications from ECE team
a. When the ECE team is ready to have their PCBs printed, hole locations and board
dimensions will be confirmed to ensure that they will conform to the shell model.
8. Make necessary changes based on tolerance issues, test results, and ECE dimensions
9. Reprint from Polycarbonate through QuickParts.
10. Order any additional parts
a. PORON® with 3M VHB adhesive
b. New gasket if shell dimensions change
c. Any other parts that are no longer adequate if changes are made
11. Assemble everything on the Polycarbonate shell
12. Retest all of the above and verify Project Completion Requirements

31
7. Appendix
7.1. Acknowledgements
The following people deserve mention for their assistance and support during the project.
At FLIR:
 Marcel Tremblay
 Jeff Frank
 Michael Kent
 Daniel Huthsing
At UCSB:
 Greg Dahlen
 Kyle Oja and Robert Albertazzi
 Ted Bennett
 Eric Matthys
 Trevor Marks
 Stephen Chen
 Steve Laguette
7.2. References
Budynas, Richard G., J. Keith. Nisbett, and Joseph Edward. Shigley. Shigley's Mechanical
Engineering Design. New York: McGraw-Hill, 2011. Print.
Johnson, K. L. Contact Mechanics. Cambridge: Cambridge UP, 1985. Print.
"Materials for Bicycle Helmets." Materials for Bicycle Helmets. N.p., n.d. Web. 14 Mar. 2014.
"Rubber Seals, Sealing Devices & O-Ring Seal Design | Apple Rubber Products." Rubber Seals,
Sealing Devices & O-Ring Seal Design | Apple Rubber Products. N.p., n.d. Web. 14 Mar.
2014.

32
7.3. Project Budget
FLIR Team 3A Budget
Total M.E. Team Budget $2,500
Drop Test Electronics $140
Drop Test Impact Materials $137
Phase Change Material $20
Charging Port $15
Power Button $20
ABS Rapid Prototype $530
Gasket $30
O-Rings $7
GORE-Vent $0
Camera Caps $15
Expenses to Date $914
Planned Expenses
Hardware $100
Water Jet Foam $100
Final Rapid Prototype $1,215
Net Total $2,329

34
7.5. Current Market Devices
Squito (Serveball) - A throwable camera with reconnaissance and
recreational applications that is capable of sending a stitched 360˚
image or video to a mobile device. Wide angle lenses minimize the
number of cameras needed to get a full panoramic image, and
position sensors allow for real time tracking.
Throwable Panoramic Ball Camera (Jonas Pfeil) -
Throwable ball device that uses 36 cameras to
capture a 360˚ image at the peak of its trajectory. Initial
acceleration data from a built in accelerometer is
numerically integrated to determine the peak of the
trajectory, where an image is automatically captured. The
enclosure is 3D printed and coated in foam to increase
impact resistance, but the device is intended to be caught
before collision.
Hero3+ (GoPro) - Robust polycarbonate camera
housing is waterproof, impact resistant, and
lightweight, making it a good model for material
selection and structural integrity of the Thermal
Sensor Cluster enclosure.
EyeBall R1 (ODF Optronics Ltd) - A deployable audio/visual
surveillance sensor that can be mounted, thrown, or rolled.
Information can be wirelessly transmitted to a portable control unit.
The device is self-righting and rotates to provide full 360 degree
coverage. This device is used by response units such as the Boston
Police Department’s SWAT team.

35
7.6. Analysis
7.6.1. Thermal
Assumptions:
Assume 5W electronic heat generation (worst case scenario from ECE team)
Exposure time: 30 minutes
Neglect contact resistances
Neglect radiation and internal convection
Assume external natural convection
Assume direct contact between camera and copper plate
Assume ambient temperature of 45 C
For the main board:
Total energy generation = 5 J/s * 30 min * 60 s/min = 9,000 J
Assume all heat flows to PCM (worst case scenario)
MPCM = (9,000 J) / (225 J/g) = 40 g  to be safe: MPCM = 80 g = 0.176 lb
Cost = 0.176 lb * 5 dollars/lb = $0.88
For the camera: Using lumped capacitance
Thermal properties:
Copper Plate: k = 400 W/m K
Aluminum: k = 205 W/m K
Convection Coefficient: h = 5 W/m2
K
Thermal Network Analysis
Camera
R1 R2
R1
Rconv
R1
Camera
(150 mW)
T1 T2 T3 Tambient
Copper Plate
Magnesium
Cap
T1
R1 = 12.94 Km/W
R2 = 1.87 Km/W
Rconv = 134.41 Km/W
T3
Tambient
T2
44.50
45.00
45.50
46.00
46.50
47.00
47.50
0 2 4 6
Temp(C)
Time (min)
Temperature vs. Time
Camera Temp
Copper Plate Temp
Aluminum Cap
Temp

36
7.6.2. Material Selection
7.6.2.1. Shell Material
Overview: Report includes explanation of material selection process for the shell material of the
enclosure. Selection was done using Granta’s CES section software and is based on determined
performance factors and limiting material properties.
Method:
Performance Index
The most likely source of failure for the shell will be due to high impact stresses which lead to
fracturing. Based on fracture mechanics, a device is estimated to undergo fracture when the
following condition holds:
(1)
√ (2)
Here is the fracture toughness ( ), C is a geometric constant,
and a is the half-length of the internal flaw. An example of typical
geometry for fracture analysis is shown in figure 1. For this situation the
amount of stress that the enclosure will undergo is proportional to its
weight. Thus it is desired to find a material that minimizes weight and
maximizes its fracture toughness. Due to the complexity of the geometry
for this device an exact relationship is very difficult to derive. Thus it
will be assumed that the performance index can be roughly defined as
the following:
(3)
This performance index is essentially a material quantity ratio that is to be maximized. For this
case very high fracture toughness and a very low density is desired. Material Strength should not
be neglected for material selection, since if the flaw size of the material is small enough, failure
may occur from yielding. Again since relating the internal stress of the shell is complicated and
depends on many factors such as the material stiffness and the impact material; let’s assume the
following simplified case where stress is proportional to the mass of the object. This gives the
following performance index:
(4)
Again it should be emphasized that these performance indices are estimates and their purpose is
to get an idea of the best performing materials for this application.
Limiting Material Properties

37
The next step in the material selection is determining what material properties are limiting
factors. For this design, a weight limit of 3lbs was established for the total device. Besides the
shell, the other big weight component is the foam material. Since this material has yet to be
selected, a conservative value of 1lb will be used for the foam weight. The weight of the camera
mount caps total at 0.391 lbs and the weight of the phase changing thermal material is 0.176 lbs.
The density of the material is thus approximately constrained by the following:
(4)
This gives a max density value of 109.24 . Material selection is further restricted to non-
metals due to Wi-Fi interference.
Results: Using the Granta’s CES selector, the performance indices given by equations 3 and 4
were plotted against each other and limits applied. The results are shown below in figure 2. The
results showed that the best performing materials are CFRP, Polycarbonate, Polyamide, and
Polyetheretherketone (PEEK).
Figure 2: Material Plot from CES selection software.
Best performing materials are in the upper right corner
The general material properties for these materials are summarized in table 1. Based on the
performance indices specified the best performing material was CFRP. A closer look at its
material properties showed its machinability is low which would make it very difficult to use for
our application since the current design requires some machining to be performed. Another
possible issue is the high stiffness which decreases its ability to absorb energy into the structure.
This heightens the chance of fracture occurring. The next best performers all showed similar

38
performance values. PEEK showed slight better performance values then polycarbonate, but its
huge cost eliminates it since the polyamide is cheaper and has higher performance values. From
the results, polyamide appears to be the best material for this application, with polycarbonate as
another possibility. This makes sense considering that both materials are commonly used for
high impact situations. It must also be noted that these material values are over a general range
and depend more specifically on different polymer blends. A common blend for polyamide that
is used for high impact situations is Nylon 6/6. Many manufactures have their own specific
blends and processes, as such further material selection should be consulted with material
providers.
Material CFRP Polycarbonate Polyamides PEEK
Density (lb/ft^3) 93.6-99.9 71.2-75.5 69.9-71.2 81.2-82.4
Price USD/lb 17-18.9 1.86-2.05 2.06-2.26 45-49.5
Young’s Modulus Mpsi 10-21.8 0.29-0.354 0.38-0.464 0.544-0.573
Yield Strength ksi 79.8-152 8.56-10.2 7.25-13.7 9.43-13.8
Fatigue Strength 10^7 ksi 21.8-43.5 3.21-4.47 5.22-9.57 4.08-5.98
Fracture Toughness ksi.in^0.5 5.57-18.2 1.91-4.19 2.02-5.11 2.49-3.91
Mechanical loss coeff (tan delta) 0.0014-0.0033 0.0164-0.0181 0.0125-0.0153 0.0101-0.0106
Max Service Temp F 284-428 214-291 230-284 462-500
Min Service Temp F -190 - -99.7 -190 - -99.7 -190 - -99.7 -190 - -99.7
Machinability 1-3 3-4 3-4 3-4
Moldability 4-5 4-5 4-5 4-5
Table 1: Material property summary
7.6.2.2. Impact Material
Overview: Report includes explanation and results of the preliminary material selection process
for the outer impact absorbing layer of the device. Selection was done using Granta’s CES
selection software.
Method: The purpose of the impact absorbing material is to effectively decrease the max
stresses on the structure by increasing the period of time that the object changes velocity. This
value is limited by the thickness of the impact material. The purpose of the material selection is
to determine a material that falls into the appropriate range of stiffness values. This analysis is
described more thoroughly in the impact analysis report. The effective stiffness of the material is
based on material dimensions and the Young’s modulus. Results of the impact analysis are
shown in figure 1.

39
Figure 1: Desired Young’s Modulus based on
varying velocity (A) and varying mass (B)
Here the figures show for a given thickness value what the optimum Young’s modulus should be
such that the full thickness of the material is used to slow down the material. Given that the max
impact velocity will be 10m/s (based off a drop from 2 stories), and for a mass range of 0.5 to
2kg, a corresponding Young’s modulus range of 0.5-3.5 MPa was determined. Since our device
may be subjected to larger impact velocities this range was extended to 16 MPa to give more
conservative options. Impact materials with in this range of Young’s Moduli are shown in
figures 3 and 4 shown in the appendix.
In order to arrow down the foam materials, a performance index was adapted based on
the energy absorption per unit volume. This can be defined by the following [1]:
cDM   (1)
:D Densification Strain
:c Compressive Stress
The most ideal material has a higher energy absorption value, meaning it makes better use of the
space it takes up.
Results: Using the above performance index in the CES software resulted in the plot shown in
figure 2. Based on this plot, polypropylene, polyurethane, and polyethylene are the best
performers.

40
Figure 2: Densification strain vs. Compressive stress for selected foams. Foams with higher energy
absorbing density are to the most right of the diagonal line
The elastomers were not included in the energy absorbing density calculations since there are no
established values for densification strain. Thus choice of material is based on figure 4.
Based on this analysis some possible elastomers and foams were determined for our
application. Further research into the different materials revealed that Polyurethane,
Polyethylene, and Neoprene foam are materials that are commonly used for impact absorption.
As such these materials will be tested in order to make further selection.

41
Additional Figures
Figure 3: Range of foam materials outputted by the CES software
Figure 4: Group of elastomers that fit into the specified modulus range.

42
7.6.3. Impact
7.6.3.1. SolidWorks Simulations
ABS impact testing without padding:
Stress:
Deflection:

43
Polycarbonate impact testing without padding:
Stress:
Deflection:

44
Nylon impact testing without padding:
Stress:
Deflection:

45
7.6.3.2. Theoretical Analysis
Overview: The purpose of this analysis is to determine a model for determining the impulse
response of a spherical shell as it hits the ground. The impulse response can then be used to
determine ideal material properties for impact materials as well as estimate internal stresses with
in the shell of the sphere. The stress analysis can then be compared against a finite element
solution of the impact to see how well the models correspond.
Method: The case being addressed here is a spherical shell dropping from a specific height.
Using energy conservation, velocity at impact can be shown by equation 1.
(1)
Now for this system lets consider the simplest motion model for the impact material which is a
spring mass system. This can be expressed as shown in equation 2.
gx
m
k
x  (2)
where k is the appropriate spring constant for the system. Solving these results in the following
expressions:
)sin())cos(1()( 2
t
v
t
g
tx n
n
imp
n
n




 (3a)
)cos()sin()( tvt
g
tx nimpn
n


 (3b)
)sin()cos()( tvtgtx nnimpn   (3c)
Where n is the natural frequency and is defined by the following:
eff
eff
n
m
k
 (4)
Using equations 3a and 3c an expression for the max acceleration and max displacement can be
expressed by the following:
22
max )( nimpvga  (5a)
2
22
2max
nn
imp
n
gvg
x















 (5b)
The effective stiffness of the system needs to be determined in terms of the sphere’s geometry
and the material properties of the impact layer. For a general block of material the stiffness is
expressed as follows:
ghvimp 2

46
t
EA
k  (6)
Where E is the Young’s modulus and t is the thickness of the material in the direction the load is
being applied. Due to the complex geometry of the spherical model, the stiffness can be
estimated using the Winkler elastic foundation model. For this model the interaction between the
infinitesimal “springs” in the model are ignored. This model is shown in figure 1. Looking at the
model it is noticed that the impact material is considered to be laid on the flat surface. Although
for our system the material is on the surface of the shell, since shear in between elements is
ignored this model is equivalent. With this model the stiffness of the impact material can be
estimated by determining how the cross-sectional area changes with deflection (figure 2). The
result of this is shown in equation 7.
Figure 1: Winkler elastic foundation model
for impact material. Here shear between
adjacent elements is ignored.
Figure 2: Visual representation of the cross
sectional area of a sphere as a function of
distance from the bottom.

47
t
EzRz
t
zEA
zk
)2()(
)(
2



(7)
Now that there is a relationship for the stiffness of the system, the impact response can now be
determined for a given geometry, material values, and impact velocity.
In order to determine the amount of stress in the shell the pressure applied to it must be
determined. For the elastic foundation model the pressure distribution can be described as
follows [1]:







R
y
R
x
h
k
h
kyxu
yxP z
22
),(
),(
22
 (8)
Where zu is the vertical defection at a point (x,y) on the horizontal plane , R is the radius of the
sphere,  is the max deflection, and h is the thickness of the impact layer. An example of the
pressure distribution shape is shown in figure 3. The stiffness over the thickness can either be
calculated explicitly, or as shown in reference [1], it can be shown as follows:
dR
E
h
k
2
*
70.1 (9a)
1
2
2
2
1
2
1* 11






 



E
v
E
v
E (9b)
This stiffness model is a numerically adjusted
model that correlates the elastic foundation model
to Hertz contact theory solution for the impact
pressure. This system also has the added
capability of factoring in the material properties of
the surface that the sphere is hitting. Due to the
additional material properties needed for this
model it will only be used for analysis of specific
materials cases. The previous stiffness model,
since not dependent on Poisson’s ratio can be
used to analyze for idea moduli of the impact
materials.
Based on hertz contact theory the principle
stresses can be determined using equations 10a
and 10b.
(10a)
(10b)

48
Here a is the contact area radius and z is the depth into the sphere. Note that this model is
typically used for solid sphere and assumes that the surfaces are smooth, the deflection is small
relative to the dimensions of the sphere, and the loading is static. These assumptions will have to
be made since there is no other simple method of determining stresses without using finite
element analysis.
With a relationship for principle stresses it is now possible to determine the von Mises
stress for given parameters. This can be used to determine whether or not failure is likely to
occur.
      2
31
2
32
2
21
2
1
 v (11)
Results: Using equations 5a, 5b, and 7, an appropriate range of young’s moduli were determined
for varying mass, impact velocity, and impact material thicknesses. The young’s modulus was
determined in Matlab by solving the differential equation and shooting for a value that allowed
for full thickness compression of the impact material. In this way the full thickness of the
material is being used to slow the sphere down, thus slowing it down over a longer time period.
This effectively reduces the max acceleration and thus the max stresses in the system. Example
solutions are shown in figures 4a-c in the appendix. For analysis of these results see the impact
material selection report.
The internal stress of the shell was determined for polycarbonate, nylon, and ABS. These
values were compared to values determined from a SolidWorks impact test. The drop height for
this analysis was 20ft and the object was dropped onto cement. The results are shown in table 1.
Figures 5a-c shows the analytical response for each material.
Material Young’s
Modulus (GPa)
Poisson’s Ratio Max Stress
SolidWorks
(MPa)
Max Stress
Analytical (MPa)
%Error
ABS 1.2 0.394 72.8 99.0 26.5
Polycarbonate 2.3 0.39 88.4 173.6 49.1
Nylon 1.6 0.3 38.7 106.2 63.6
Table 1: Comparison of max stress results from both finite analysis and
the analytical model derived in this report.
The results appeared to agree for the ABS, but the results for the two other materials had large
amount of deviation. This was somewhat expected due to the assumptions that had to made for
the analytical model, those being a solid sphere with smooth surface. The finite model, however,
was able to factor in the shell geometry, which intuitively would make the model less stiff and
thus decreases the total stress. The results shown in table 1 agree with this theory since the finite
models had considerably less stress then the analytical model. Although the results don’t

49
completely match up they are at the very least on the same order of magnitude, confirming that
both analysis techniques are somewhat reasonable for approximating stresses.
Additional Figures
(a) (b)
(c)
Figure 4: Example results for impact material optimization. Part a gives results for varying
masses for 10m/s impact velocity while part b gives results for varying impact velocities for a
1.5 kg system. Part c shows the resulting max accelerations for different impact velocities.

50
(a) (b)
(c)
Figure 5: Plots show internal stress of the spherical shell for various materials. The material values for
this test are shown in table 1. Plots show both the principle stresses and the resulting von Mises stress.

51
O-Ring Design:
O-Ring Stretch
Target: Min=1% Max=5%
Percent Compression
Gland Fill
Squeeze
Target: Min=10% Max =40%

52
Gasket Design
Area=4.364in^2
L=.0625in
E=3 MPa= 435 psi
=
𝐴
𝐿
= 30373 /
∆𝑥 = .0675 .054 = .0135
Gasket Thickness Tolerance +/-.005 in
Design for worst case scenario Gasket is thicker
than 1/16”.
Gasket Thickness = 1/16+.005=.0675 in
For Max Compression of 50% Gasket thickness = .0675*.5=.03375in
For Compression of 20% Gasket Thickness = .0675*.8 = .054 in
Therefore height of the lockout piece should be .054in tall, and the height of the lip should be .02025in.
= ∆𝑥 = 410
Force per screw = F/5 = 82 lb

53
7.7. Test Procedures
7.7.1. Drop Test
Table of Contents
1.0 Introduction Page 3
2.0 Reference Documents Page 4
3.0 Test Configuration Page 4
4.0 Test Procedures Page 7
List of Figures
Figure 1 Page 4
Figure 2 Page 5
Figure 3 Page 5
List of Tables
Table 1 Page 7
Acronyms
TS – Test Subject
IM – Impact Material
1.0 Introduction
1.1 Purpose
The purpose of the TP01 is to ensure repeatable tests and consistent data collection in the
investigation of IMs. The test consists of dropping the TS (full prototype or spherical
substitution) from varying heights onto various types of IMs.
1.2 Objectives
The objective of TP01 is to observe the impulse response of various IMs to a given mass dropped
from heights of up to 15ft. The rebound height is used to determine the energy dissipation of
the IM and the peak acceleration is used to determine the peak stresses experienced by the TS.

54
1.3 Importance
Maximum energy dissipation is desirable to ensure that the IM is most efficiently utilized in
reducing the shock experienced by the TS. An IM that is too thin or soft results in the TS
bottoming out and experiencing more direct impact with the cement. An IM that is too stiff for a
given mass will not make use of its full elastic potential in decelerating the TS. An optimal
thickness and durometer are to be determined in order to minimize the negative effects of
impact on the TS.
1.4 Background
In order to maintain a low profile while effectively reducing the stresses experienced by the TS,
it is important to determine an IM that is stiff enough to decelerate the TS but soft enough to
reach a near-maximum compression. A combination of ascending durometers of IM stacked on
top of one another is expected to have the best results. Additionally, the visco-elastic behavior
that some IMs offer is desirable so as to minimize the restoring elastic force on the TS.
2.0 Reference Documents
Arduino Uno Specifications:
http://arduino.cc/en/Main/arduinoBoardUno
Adafruit Data Logger Shield Specifications:
http://learn.adafruit.com/adafruit-data-logger-shield
Analog Devices ADXL377 Accelerometer Specifications:
http://www.analog.com/en/mems-sensors/mems-accelerometers/adxl377/products/product.html
3.0 Test Configuration
3.1 Test Approach
A low power, 3 axis accelerometer is tightly secured flush to the inside bracket of the TS via two
#4 machine screws. A 6-band ribbon wire is attached to the accelerometer and is taped to the
strain relief bracket on the opposite side of the TS (Figure 1).
The ribbon wire connects the X, Y, and Z outputs, +3V power supply, and ground cable of the
accelerometer to a data logger (Figure 2). The data logger mounts to an Arduino Uno
Figure 1: Test subject with
accelerometer screwed to
mounting bracket and ribbon wire
taped to strain relief bracket.

55
microcontroller board. The Arduino Uno is powered by and connected to a laptop via mUSB
cable.
Figure 2: ADXL377 accelerometer function block diagram (left) and Adafruit Assembled Data
Logging Shield (right).
A tape measure is mounted from the ground to an elevated fixture (balcony), using a mass hung
by a string to determine approximate vertical orientation. One tester holds two sides of the TS
and raises the bottom of the TS to the desired test height. Once the data logger and
photographer indicate that they are ready, the tester carefully releases the TS so as to prevent
any considerable rotation. The TS is dropped onto the IM (or plain cement for the control group)
(Figure 3). Arduino software commands the data logger to record the instantaneous
acceleration while a high-speed camera records the trajectory of the TS.
Figure 3: Demonstration of drop procedure

56
3.2 Equipment Needed
 Test subject (hemispherical shape or prototype)
 2x mounting brackets (aluminum)
 2x mounting bracket screws
 Analog Devices ADXL377 Low Power, 3-Axis ±200g Accelerometer
 2x accelerometer screws (#4)
 6-band ribbon wire (25ft)
 Adafruit Assembled Data Logging Shield for Arduino
 SD Card
 Arduino Uno microcontroller board
 mUSB cable
 Laptop with Arduino software
 Canon EOS Rebel SL1 camera
 Tripod
 Tape measure (25ft)
 Mass with hook (arbitrary mass)
 String
 Impact materials
3.3 Test Reporting Requirements
The data is exported from the SD Card to Excel as a .csv file. The test number logged by the data
logger is matched with the test number stated prior to each drop by the tester operating the
camera. The acceleration data (raw voltage) is converted to an acceleration value. The
maximum rebound height recorded by the camera is noted.
Outlier data, determined by a predefined margin of error or an observed infraction of test
procedure, is to be marked for later deletion.

57
4.0 Test Procedures
This section lists the step-by-step procedures to be followed for each test. Other information to be
included is the expected result and the requirements to be verified.
Step Procedure Expected Result
1 Center IM at base of tape measure.
A dropped object should fall directly in the
center of the IM.
2
Raise bottom of TS to desired drop
height.
A second person must verify that the bottom
of the TS lines up with the correct height on
the tape measure from a horizontal
perspective.
3
Begin data logger using command
from Arduino software.
A timer should pop up on the Arduino
software interface.
4
Start recording video and clearly
state the test number.
Recording light flashes.
5 Carefully drop TS. Minimal/negligible rotation after release.
6
After TS rebounds to max height,
quickly reach out to catch TS.
Catcher’s arms should be clear from video
shot and should not interfere with the TS’s
trajectory.
Table 1: Test Procedures

58
7.7.2. Thermal Test
Table of Contents
1.0 Introduction Page 3
2.0 Reference Documents Page 3
3.0 Test Configuration Page 4
4.0 Test Procedures Page 4
List of Figures
List of Tables
Table 1 Page 4
Acronyms
TS – Test Subject
PCM – Phase Changing Material
1.0 Introduction
1.1 Purpose
The purpose of TP02 is to ensure repeatable tests and consistent data collection in the
investigation of the transient thermal behavior of the test subject (TS). The test consists of
placing the TS in a thermal chamber and measuring the temperature change of interior points of
the TS over time.
1.2 Objectives
The objective of TP02 is to test whether the internal components of the TS reach their maximum
operating temperature within the given time. Additionally, the phase changing material (PCM) is
observed to ensure that it activates at the intended temperature.
1.3 Importance
It is important not to exceed the maximum operating temperature of the electronic
components. If they are exceeded, the components may fail or not work as intended. By
monitoring various locations throughout the TS, points of low heat dissipation can be detected
and addressed.
1.4 Background

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