Preliminary Design Review

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High Altitude Balloon
Payload Design Project
Critical Design Review
July 17, 2012
Design Team:
Jen Hoff (EE)
Kate Ferris (EE)
Alison Figueira (CS)
Makenzie Guyer (CS)
Kaysha Young (ME/MET)
Emily Bishop (ME)
Advisors:
Dr. Brock J. LaMeres -Electrical & Computer Engineering
Dr. Angela Des Jardins -Montana Space Grant Consortium
Hunter Lloyd -Computer Science
Robb Larson -Mechanical & Industrial Engineering
Sponsor:
NASA
Mission Objective
To collect measurements
at high altitudes of
atmospheric
temperature and
pressure, the internal
temperature and
dynamic movement of a
payload that meets HASP
flight requirements.
Budget: $500
Schedule: 8 Weeks
6/4/12 -7/27/12
Mission Requirements
Functional Requirements
Log/Store data from the sensors on a non-viotile storage device
Power Sensors and any electronics needed to run these sensors
Protect the system from environmental conditions
Protected from the impact upon landing/jerk from the balloon
pop
Provide state of health information of the system
Performance Requirements
Consume 5 watts in order to accurately represent the research
team’s thermal output
Log data from the temperature and pressure sensors at a rate of
1 measurement per second
Provide insulation to keep the internal temperature between -40
C and 60C
Must provide at least 4 hours of power for the duration of the
setup, flight, and recovery time.
Must withstand an vertical force of 10 G and a horizontal force of
5G
Physical Requirements
Must weight 1.62 kg
Maximum Total Volume: 15 cm x 15 cm x 30 cm
Must mechanically interface with the HASP payload plate in addition to
the BOREALIS system
Reliability Requirements
Must be able to survive preliminary tests and two launches
System Architecture
2012 Payload
Computer System
Electrical System
Mechanical System
Computer System
2012
Payload
Computer System
Computer
System
Electrical
System
Mechanical
System
Logging Data
SD Card
SD Shield
Interpreting Data
Reading from
Sensors
Start
Program Flow Chart
Retrieve Data
Setup: Start LED’s, define pins,
startup SD library, startup IMU,
define timers
Get Accelerometer
and Gyroscope
Values
Interpret Data
Loop: Update
Timers, average
IMU data
Average Values
Analog Sensors
Timer goes off Event
Store current
averages in Array
IMU Event
Store IMU averages to SD
card with timestamp (millis)
Reset current averages
and clear average array
Store in RAM
Store on SD card, with
timestamp (millis)
Goes through same process
for Pressure Sensor, and all
Three Temperature Sensors
Testing
• SD card
• Timer Events
• SD card, RTC
(not used), and
timers
• Reading from
Analog Sensors
• Reading from
IMU
Testing Cont.
• Timer
Events
Testing Cont.
• SD card,
RTC, and
timers
Testing Cont.
• Reading
From
Analog
Sensors
Data from Burn In Test
RTC was not working
correctly, addressing
problem with
Gyroscope, but it was
able to record and store
data for the duration of
the Burn In Test
Cold Test
• In the second cold test,
only the analog sensor
data was collected.
• Problem with
temperature sensors
• Collected data every
second for duration.
• 5753462 milliseconds
~ 95.891 minutes
Refrigerator Test
• After getting new
temperature sensors, the
computer and sensor
were placed in the fridge
for ~10 min. trials.
• The fridge got down to
8C.
Flight Plan
• For the first flight, just the analog sensors (pressure
and three temperature) will be used.
• Between flights the IMU will be tested (addressing
issue is fixed)
• Second flight will have all sensors hooked up.
Budget
Budget
Unit
Price
Shipping Total
Arduino Uno R3
29.95
13.25
43.2
Adafruit Data Logger
19.5
0
19.5
Total
62.7
Electrical System
2012
Payload
Computer
System
Electrical
System
Electrical System
Mechanical
System
Sensors
Interfacing
Power
System
Batteries
Temperature
Pressure
Movement
Acceleration
Schematic
Burn In Test
Burn In Test Results
BURN-IN TEST
TIME
VOLTAGE of Batteries
CURRENT from Batteries
VOLTAGE 3.3
CURRENT from 3.3
0 minutes
14.2 V
0.07 A
3.29 V
7.8 mA
5 minutes
12.4 V
0.068 A
3.298 V
7.6 mA
10 minutes
12.13 V
0.0689 A
3.299 V
7.8 mA
15 minutes
12.068 V
0.068 A
3.299 V
7.7 mA
20 minutes
12.057 V
0.0685 A
3.2999 V
7.7 mA
25 minutes
12.056 V
0.068 A
3.2999 V
7.6 mA
30 minutes
12.046 V
0.071 A
3.2999 V
6.8 mA
35 minutes
12.05 V
0.071 A
3.2999 V
6.8 mA
40 minutes
12.056 V
0.071 A
3.2999 V
6.8 mA
45 minutes
12.061 V
0.071 A
3.2999 V
6.8 mA
50 minutes
12.063 V
0.071 A
3.2999 V
6.8 mA
60 minutes
12.069 V
0.071 A
3.2999 V
6.8 mA
70 minutes
12.073 V
0.071 A
3.2999 V
6.8 mA
80 minutes
12.076 V
0.071 A
3.2999 V
6.8 mA
90 minutes
12.079 V
0.071 A
3.2999 V
6.8 mA
100 minutes
12.080 V
0.071 A
3.2998 V
6.8 mA
130 minutes
12.083 V
0.071 A
3.2998 V
6.8 mA
160 minutes
12.087 V
0.071 A
3.299 V
6.8 mA
190 minutes
12.088 V
0.071 A
3.299 V
6.8 mA
220 minutes
12.088 V
0.071 A
3.299 V
6.8 mA
Burn In Test
 Total Discharge
 Needed to add power
resistors which updated
the current pulled from
the batteries to
0.241919771 A
Cold Test
 Cold Test
 Put the temp sensor
into the fridge with an
external temp sensor
and recorded the values
of the test.
Output Wattage
 Power Resistors
 Needed to add 2W to the inside of the payload to reach the required
5W
Output Wattage
Pressure:
Temp Sensors:
Batteries:
Power Resistor:
0.00528
0.0165
2.915037
2.063
Total:
4.999817
P=I*V
Mass Budget
 Mass of the inside of the Payload
 Weighted 0.73lbs.
Budget
Sensors(+shipping): $122.92
Batteries:
$82.32
Battery Boxes:
$4.58
PC Board:
$12.81
Headers:
$12.76
Total:
$237.86
Mechanical System
2012
Payload
Mechanical System
Computer
System
Electrical
System
Mechanical
System
Structural
System
Enclosure
Thermal
Impact
Attachment
Material
Structure
Temperature
Mechanical Systems
Requirements
Thermal
Structural System
i. Must be similar to the MSU HASP Research Team
structure materials
1.Polystyrene must be used for the insulation
(approx. 1 cm thickness)
2.A shiny reflective aluminum coating should
be applied
3.Additional material or support structures
will be needed to make the structure strong
ii. The internal temperature of the payload must be
kept between -40 C and 60 C
i. Enclosure
1. The external volume may not exceed 5.875 in x
5.875 in x 11.8 in (15 cm x 15 cm x 30 cm)
2. The internal volume must be at least 131.6 in3 : 4.5
in x 4.5 in x 6.5 in
ii. Attach Enclosure Structure
1. HASP
1. Enclosure must securely attach to HASP Plate
and not be disconnected for the duration of the
flight
2. Must be easily attached and unattached
from the ASP plate for ease of assembly and
disassembly
2. BOREALIS
1.Must attach to the BOREALIS rope connection
system
iii. Impact Forces
1. Must withstand a vertical impulse force of 10 G’s
2. Must withstand a horizontal impulse force of 5 G’s
Preliminary Design Review
Results
Immediate Changes to the
PDR
** Reduced height to 6 inches
** Choose to not use corner rebar
wire
** Changed L Brackets to Corner
Brackets
** Not using Plaskolite
Assembly : Initial Trials
Fiberglass and Resin + foam = disaster
Fiberglass and Resin + Aluminum foil +
duck tape = success
New Design Implementations
Improved Design Considerations
Implementing Technique
• Access Electronics while they are
attached to HASP Plate
• Make the top and one side
panel removable
• No Reflective surfaces as not to
interfere with other HASP
Payloads
• Paint the exterior white
• HASP Power Cord entrance
• Cut a small aperture at the
back of the payload for
cords to run in.
Payload : Structural Elements
Structural Support
Enhancers:
Material Configuration
* Fiber Glass Cloth
* Corner Brackets
White Reflective
Paint
Fiber Glass Cloth
W/ resin
0.5” thick Expanded
Polystyrene Insulation
Payload :Electronic Stabilization
* 4-40 Hex Socket Cap Screws
Payload : Exterior Surface
Krylon Flat White Paint
- Chosen by the HASP team due
to research done by prior space
flight teams from MSU
Payload : Assembly
-HASP Plate
-High Conductive Copper Heat Sink
-3 walled structure
-1 wall
- 1 top
-17 – 10-32 x ½” button head screws
- 4 – 10-32 x 1” button head screws
-4 – 4-40 x 1.25” hex socket cap screws
- 4- 4-40 x 2.0” hex socket cap screws
Payload : Attachment to HASP
•Corner Brackets
• 4 – 10 32 x 1”
button head
screws
•4 - #10 Nuts
Payload : Attachment to BOREALIS
Due to odd shape and unevenly distributed weight, the BOREALIS Team
is configuring an attachment plan.
Mechanical System - Testing
Type of Test
-Drop Test
-Long Term
Thermal Test
What will be Tested
- Accelerometers
-Structure components
-Insulation
-Heat Sink
Test #1 : Drop Tests
Accelerometer Testing
** Must withstand a 10 G
vertical load
** Must withstand a 5 G
horizontal load
Test:
The accelerometer was attached
to the inside of the box with duct
tape. A lab view program was set
up to collect acceleration data from
X, Y, Z, and Total Acceleration. The
interior was padded with packing
foam. The box was dropped from
various heights, ensuring that the G
loads were met.
Test #1 : Drop Test Results
Vertical Test
Horizontal Test
Maximum Load: 15 G
Maximum Load : X - 8 G
Y – 10 G
Test #1 : Drop Test Results
A drop test was
completed to test the
ability of the box to
withstand a much higher
load.
The over all acceleration
reached over 20 G, and the
vertical load reached 19 G.
The enclosure showed
no signs of wear or tear
after these tests
The enclosure will
withstand the G loads
required by HASP
Test #2: Thermal Test
Cold Room Test:
*Cold room at -60 C
*Raise temperature to 20C
*No results due to
failure to collect data
from temperature
sensors due to
electronic problems
Mechanical Systems Mass Budget
Mechanical Systems Mass Budget
Quantity Weight/Piece (g)
Extruded Polystyrene
1
150
Total Weight
150
Fiber Glass and Resin
1
22.5
22.5
Brackets
4
28.576
114.304
Bracket Mounting
Hardware
4
17.2368
68.9472
HASP Mounting Material
4
9.9804
39.9216
CCA Stack Mounting
Standoff
4
10.4338
41.7352
Total Mass
840.51
Mechanical System Budget
Material
Cost
Extruded Polystyrene
$12.25
Brackets & Assembly Hardware
8.58
Mounting Hardware
5.48
Heat Sink
34.95
Miscellaneous Assembly Materials
(fiberglass, resin, acetone, duct
tape, gorilla glue, etc)
68.81
Paint
11.95
Total
142.02
Total Budget
Computer Science:
Electrical:
Mechanical:
$62.70
$237.86
$142.04
Total:
Under budget:
$442.60
$57.40
Final Configuration
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