Colorado Space Grant Consortium
GATEWAY TO SPACE
FALL 2007
DESIGN DOCUMENT
Team McLovin
Written By: Deniz Bertuna, Tyler Drake, Jason Hohl, Gavin Kutil, Ryan Quakenbush, Gauravdev Singh Soin
November 9, 2007
Revision C
Revision / Description / DateA / Conceptual Design Review / October 4, 2007
B / Preliminary Design Review / October 17, 2007
C / Critical Design Review / November 9, 2007
D / Analysis and Final Report / November 29, 2007
Revision Log
Table of Contents
1.0 Mission Overview…………………………………………………………………………….4
1.1 Objective
1.2 Experiments
1.3 Expected Results
2.0 Requirements Flow Down……………………………………………………………………5
3.0 Design………………………………………………………………………………………..7
3.1 Parts
3.2 Drawings
3.3 Functional Block Diagram
3.4 Final Part List
4.0 Management…………………………………………………………………………………11
4.1 Organizational Chart
4.2 Schedule
5.0 Budget……………………………………………………………………………………….13
5.1 Mass
5.2 Money
6.0 Test Plan and Results………………………………………………………………………..14
6.0.1 Stair Test
6.0.2 Whip Test
6.0.3 Drop Test
6.0.4 Cooler Test
6.0.5 Photometer Testing and Calibration
6.1 Testing Results
6.1.1 Stair Test
6.1.2 Whip Test
6.1.3 Drop Test
6.1.4 Flammability Test
6.1.5 Conductivity Test
6.1.6 Photometer Test
6.1.7 Camera Test
6.1.8 Cooler Test
6.1.9 HOBO Test
7.0 Expected Results…………………………………………………………………………….17
8.0 Launch and Recovery.…...………………………………………………………………….18
8.1 Plan for Launch and Recovery
1.0 Mission Overview
1.1 Objective
The objective of our team mission is to test and build a satellite that will be sent to approximately thirty kilometers and measure light intensity at different atmospheric levels and take high quality images. The team wishes to further the studies of light intensity being performed by Professors Brown and Fesen in their efforts to create a low budget, high quality, near space platform for astronomical purposes.
1.2 Experiments
The light intensity experiment will be using one light sensitive photo diode placed in the upper corner of the cube at a slant of forty five degrees. A PVC pipe will direct sunlight onto a specific area in the diodes which will then use this light to analyze the different regions of the light spectrum.
A high mega pixel digital camera will be used to take high quality pictures of the upper atmosphere as well as of the journey during ascent and descent.
1.3 Expected Results
The main expectations are to formulate an average value of light intensity at various altitudes to further promote the research of Professors Brown and Fesen in hopes of advancing the field of low cost near space astronomy. Our results will provide data that will be used to decide whether or not Hubble quality images provided from near space astronomy will be possible during day light hours.
2.0 Requirements Flow Down
To launch and recover a BalloonSat sent to an altitude of 30 kilometers, and perform scientific experiments to measure light intensity up to that altitude.
.
Mission Statement / To launch and recover a BalloonSat sent to an altitude of 30 kilometers, and perform scientific experiments to measure light intensity up to that altitude; while periodically capturing photographs.Mission Objectives /
- Construct a BalloonSat to test light intensity at high altitudes.
- Measure light in the infrared frequency.
- Record temperature of the photodiode.
- Obtain high altitude photographs
Level 0
(Objective Requirements) / 0.1)Construct a BalloonSat in order to improve or understanding of light intensity between the altitudes of 15 and 30 kilometers with a budget of $200.00, and a weight less than or equal to 800 gramsby November 10, 2007
0.2)Measure light in the infrared frequency in nanometers at different atmospheric altitudes.
0.3)Track the temperature (˚C) of the photodiode to correctly evaluate dark current noise effects on data.
0.4)Obtain high quality images of the curvature of the earth at 30 kilometers.
0.5)Keep the inside of the BalloonSat above 0 ˚C
Level 1
(System Requirements) / 1.1)The Balloonsat, excluding the photometer, must be maintained at an optimal temperature of 25 ˚C.
1.2)The photometer
1.3)The balloonsat must be connected to an inverted plastic tube will be fixed through the center of the balloonsat. The rope, which is tied to the balloon, is threaded and knotted through the tube.
1.4)Balloonsat must be carried by a latex balloon filled with helium, carrying a parachute deploying on burst, and capable of carrying a net payload of twelve kilograms
Level 2
(Subsystems Requirements) / 2.1) The photodiode circuit is connected to the Basic Stamp, where all of the data from the photometer will be stored.
2.2) The Basic Stamp will be preprogrammed to record the data in the proper format.
2.3) The camera will be connected to the power source via a switch. The operation of the camera will be controlled by a timing circuit which will be programmed to take photographs at regular intervals of one minute.
2.4) The HOBO will consist of two sensors, one recording external temperature of the balloonsat and the other recording internal temperature in ˚C.
2.5) The heating unit must operate properly to ensure that the subsystems (excluding the photodiode) will function even though the exterior of the balloonsat will experience temperature extremes of -70 ˚C. Insulation will also be used to keep the BalloonSat above the required 0 ˚C
2.6) In order for the balloon to reach its desired altitude of 30 kilometers, each system has to obey the 800 grams weight limit. The balloon will also carry a parachute, to ensure a soft landing velocity of nearly 100 kilometers an hour, and a GPS tracking system to help the team recover the balloonsat.
3.0Design
As a requirement the BalloonSat will be less than 800 grams. At the top of the BalloonSat we have a trapezoid from two sides along the edges through which the photometer is partly sticking out of the satellite, so it will be a challenge to keep it in their optimal position and prevent it from tilting. Positioning of the different subsystems inside the satellite once the insulation has been placed in, will also be a challenge due to the narrow design of the top.
The structure of the satellite will be made of foam core with hot glue connecting sides with aluminum tape. The design of the BalloonSat is based on the proper functioning of the photo diode for the light intensity experiment. The diode has to be placed at an angle forty five degrees with the horizontal. The base part of the satellite will be in a rectangular shape with the dimensions of 25 cm by 10 cm. The height of the cuboidal structure is 15 cm. Above the cuboidal structure we have combined two rectangular sides with two trapezoidal sides. The rectangular sides will be at angle of thirty degrees with the horizontal, and the trapezoids will come up straight, so as to form a roof top type structure with two sides slanting for the housing of the photo diode. The top part after the slants will be a rectangle of 10 cm by 15 cm. The height of the slants will be 10 cm each. The flight string will pass through the center of the top of the satellite and travel straight down through the base. Washers will be placed to keep the BalloonSat from not sliding down the flight string.
The camera will be placed on one of the sides against the wall of the cuboidal structure. The HOBO will be placed caddy corner of the camera. The HOBO sensor will be sticking out of the adjacent wall. The heater will be placed on the base in the middle of the cuboid, as to spread the heat all around the structure to keep all subsystems functioning correctly. The BASIC stamp will be placed opposite of the camera on the other wall of the cuboid. The cold fingers for the photometers will be sticking out of the rectangular top. The condensation packs will be spread out throughout the structure as to keep all subsystems from experiencing condensation.
To keep the BalloonSat above the required temperature of 0 ˚C, insulation will be placed on the inside of the structural walls to maintain a warm temperature for all the equipment inside. Along with the heater placed in the payload, the insulation will further the warmth of all the experiments.
Each subsystem will have an isolated power source, so that if any one experiment fails, the others will go on uninterrupted.
3.1 Parts
-Low dark current silicon photodiode
-OPA129 Integrator
-OPA27 op amp voltage follower
-1000 pF Panasonic metalized polypropylene film capacitor
-DIP-packaged reed relay
-LM335 temperature detection circuit
-4.1 inch PVC pipe with a diameter of 1.5-1.25 inch
-1 x 1/18 aluminum bar
-Plano-convex lens of 30mm diameter and 25mm focal length
-HOBO, BASIC Stamp
-Digital Camera with timing circuit
-Foam Core
-Condensation Gel Packets
-Insulation
3.2 Drawings
3.3 Functional Block Diagram
3.4 Final Parts List
-Low dark current silicon photodiode
-OPA129 Integrator
-OPA27 op amp voltage follower
-1000 pF Panasonic metalized polypropylene film capacitor
-DIP-packaged reed relay
-LM335 temperature detection circuit
-4.1 inch PVC pipe with a diameter of 1.25 inches
-1 x 1/18 aluminum bar
-Plano-convex lens of 30mm diameter and 25mm focal length
-HOBO, BASIC Stamp
-Red Light Filter
-Digital Camera with timing circuit
-Foam Core
-Silicon Condensation Packets
-Insulation
-Aluminum Tape
-Thermal Blanket
4.0 Management
4.1 Organizational Chart
4.2 Schedule
September 16 / First RFP Meeting19 / Discuss RFP and Presentation Finalized
20 / RFP Due
27 / Team meeting
30 / DDREV A work
October 2 / DDREV A work
3 / DDREV A work and completion
4 / DDREV A and presentation due
7 / Final Hardware and concept decision
9 / Team meeting
10 / DDREV B work
11 / Order hardware in class
14 / DDREV B completion
16 / DDREV B due
17 / Begin building of prototypes
21 / Stair tests 1&2, Whip tests 1&2
23 / Review Previous tests, begin final build
24 / Begin integration of inner components
28 / Weigh Satellite, cooler test 1
30 / Cooler test 2, DDREV C work
31 / Final Tests, DDREV C work, acquire spare parts
November 4 / Test review and Final structure changes
7 / Compile all launch info and documents; Prep for DDREV C presentation
8 / In-class Launch readiness review
9 / DDREV C due, final weigh-in
10 / Launch Date
11 / Debriefing meeting, Transfer and analyze recovered data
13 / Data analysis continued
14 / DDREV D work
15 / Finish DDREV D work, begin satellite repair
25 / Prepare final presentation
27 / Finish Final presentation, Complete repairs
28 / Practice DDREV D Presentation
29 / DDREV D Due
December 2 / Prepare for Final Presentation
4 / Final Presentation
Launch Day
5 AM- Leave Boulder, CO
6:30-7:30 AM- Arrive at Windsor, CO
- Perform Final Systems Checks,
- Check batteries and replace if necessary
- Check structural integrity of satellite
- Clean all lenses
- Check camera and photometer
7:30 AM- Power up all systems and prepare for flight
- Go For Launch
7:30 onwards- Trace and Recover Satellite
Post Recovery- Recover satellite
- Check for any damage to equipment and structure
- Check all components, data equipment drives
5.0 Budget
5.1 Mass
Item / # of Items / Individual Mass (grams)Structure / 1 / 243
HOBO Data Logger / 1 / 35
Photometer Unit w/ BASIC / 1 / 94
Cold Finger / 1 / 45
Red Filter / 1 / 18
PVC Pipe / 1 / 66
Heating Unit / 1 / 172
Digital Camera w/ Timing Circuit / 1 / 225
Battery packs / 2 / 5
Condensation Gel Packs / 4 / 4
Plexiglas / 1 / 17
Washers / 2 / 8
Piping / 1 / 12
Total: / 944 grams
5.2 Money
Item / # of Items / Individual Item Cost ($)Structure / 1 / -
HOBO Data Logger / 1 / -
Photometer / 1 / -
Heating Unit / 1 / -
Batteries 9V (Heater) / 3 / -
Digital Camera / 1 / -
Timing Circuit / 1 / -
Battery packs / 1 / -
Condensation Gel Packs / 4 / -
Batteries 12 V (Timer) / 1 / -
BASIC Stamp / 1 / $54.95
Home Depot Parts (PVP pipe, laser level, screws, nuts, ruler, Plexiglas, Plexiglas cutter, black spray paint) / $57.00
Red Filter / 1 / $15.00
12 V Battery packs / 4 / $20.00
Total Cost / $146.95
6.0 Test Plan and Results
Structural
Stair test
Whip test
Drop test
Subsystems test
Cooler/ heater
Light/ photodiode
Electrical
HOBO
BASIC stamp
Camera and timing circuit
Heater
In order for our group to have a successful flight and collect substantial data, several tests will need to be performed on both our satellite structure and its inner components. Our group established a detailed day-by-day test schedule to ensure a successful mission. Most importantly, our group needs to test our photodiode because our data will not only reflect our success as a group but also will provide data for the further studies of Dr. Brown and Dr. Fesen. Our group aims to have complete confidence in both our structural and subsystems designs. With that in mind, our group will conduct multiple tests using different conditions. From there our group will utilize this information and apply that to out separate designs for best performance. The way that the group will determine which tests were more successful than others will be by means of video photography. With that the data can be analyzed and then properly utilized.
6.0.1 Stair Test
The stair test will be implemented to test the structure of the BallonSat. If the parachute of the balloon fails, the payload needs to survive a harsh landing, which is what the stair test is designed to do.
6.0.2 Whip Test
To simulate the flight the BalloonSat will experience once the balloon pops at its maximum altitude. By attaching a cord to the satellite it will be spun around to simulate flight.
6.0.3 Drop Test
Incase the parachute fails to deploy, the satellite will be put to very high velocities, so the payload will be dropped from a height of twenty meters to simulate the landing force it could experience.
6.0.4 Cooler Test
The payload will experience extreme cold temperatures during flight; by making sure all the experiments function properly, the BalloonSat will be placed in a cooler of dry ice for three hours to experience how long it will be in flight in these extreme temperatures
6.0. 5 Photometer Testing and Calibration
The photodiode must first be calibrated to record accurate data. The current plan involves exposing the photodiode to a know wavelength in a completely dark room to learn the variation constant. This can most easily be done with a laser pointer of known frequency. Testing on the photometer will mostly involve the circuit and basic stamp functioning compatibly together.
6.1 Testing Results
6.1.1 Stair Test
Two sets of this test were performed on the multilayer stairs of the DLC. One round of testing was done on a prototype with no inner mass, while another was performed using a prototype with a mass approximately similar (650g) to the final product. Two rounds of this test were performed on each of the two masses. While the prototype of lesser mass, when pitched down the two flights of stairs, sustained almost no damage aside from a few corner dents, the greater mass prototype sustained a few larger dents when pitched down the stairs. However, structural integrity was not compromised and the inner components took no damage. We gathered from this test that, as mass increases, so does susceptibility to damage. Both prototypes passed the stair test.
6.1.2 Whip Test
This test was performed by four of our six team members at 20 swings per person. A string of approximately two meters in length was strung through the center tubing of our satellite structure with a metal washer on the bottom end to keep the structure on the string. The satellite easily withstood the whipping forces endured in this test. The structure was whipped around at multiple angles in order to simulate the in flight g-forces that may be experienced. The inner components of the satellite will need to be secured more than they were in the test even though no serious damage occurred to the components during the test. The whip test was passed by the structure.
6.1.3 Drop Test
This test was performed from the bridge between the ITLL and the DLC with two repetitions onto both grass and cement. It was performed using a prototype of similar mass to our final product. Several items of different levels of frailties were placed inside to see how the structure would protect them, such as a working circuit with flashing LEDs and a box of nails. Different methods were also used for placing Plexiglas in two different holes to see which method of placement would be more stable. This is the method we will use for the Plexiglas sheet in front of our camera. The cement landings caused denting on a few of the corners and edges from impact. The grass landings also caused minor denting; however, nothing like the cement landings. The structure remained intact despite the rough landings and dents it received. It also kept the inner components in one piece and operating in the case of the circuit, however more restraint of the components is needed. The best method of placing Plexiglas (placing a larger section on the inside of the structure over a smaller hole instead of placing a piece of equal size to the hole flush with the structure wall) was also determined. A larger piece of Plexiglas over a smaller structure hole was much more stable and the glass stayed attached to the structure longer when this method was compared to the other. The structure passed the multiple drop tests.
6.1.4 Flammability Test
The flammability test was performed to see if the heating circuit overheated if it caused the thermal blanket inside and the insulation to catch on fire. During the testing both did catch on fire so it is necessary that we add a piece of foam core under the heating circuit to prevent this from happening during flight.
6.1.5 Conductivity Test
This test was designed to see if by placing the timing circuit on the thermal blanket would cause shortages with the circuit. We put the timing circuit to take a picture every 50 seconds, and then placed it on the thermal blanket. When it was turned on the circuit started to short out and caused it to take pictures at random intervals and ended up not working. To prevent this from happening we placed a piece of foam core under the timing circuit in the inside of the BalloonSat and it passed the test, it does not start to short out.
6.1.6 Photometer Test
Circuit Test-
With the help of Tim May we were able to successfully complete the photometer circuit and although we were unable to finish the BASIC Stamp programming in time to be able to test the circuit with the program. However, we did successfully manage to test the circuit isolated from the BASIC Stamp and observed that our photo voltage using which we will calculate the photo current did rise at the desired rate depending upon the light intensity in the room.