BalloonSat Missions to the Edge of Space

Transcription

1 The Colorado Space Grant Consortium, The University of Colorado at Boulder Department of Aerospace Engineering Sciences, and the Edge of Space Sciences present BalloonSat Missions to the Edge of Space Request For Proposal #RFP 2500F08 Fall 2008 Announcement Proposal Due No Later Than: DATE: September 23, 2008 TIME: 5:00 PM RFP 2500F08 1

2 Introduction The Colorado Space Grant Consortium, the CU Aerospace Engineering Sciences Department, and the Edge of Space Sciences are accepting proposals for the BalloonSat Missions to the Edge of Space for launch in November 15, This request (RFP 2500F08) will allow teams to submit proposals for up to $150. In addition, each team will be provided with (expected to fly) a digital camera and 1GB memory card, timing circuit kit, HOBO data logger with internal and external temperature sensors, heater kit, switches, foam core, batteries (limited), aluminum tape, and other miscellaneous items that are available or required. This hardware is valued at over $350. The organizations listed above expect to award approximately $1,650 under this solicitation and reserves the right to partially fund proposals. Pertinent Dates Date of Announcement: September 11, 2008 Proposal Due Date: September 23, 2008 Award Announcement: September 30, 2008 Design Document Rev D Due Date: December 2, 2008 Eligibility Requirements Proposals will be accepted from the teams associated with the Gateway to Space course (ASEN 2500 and ASTR 2500). One proposal per team. Background This program is now in its 12th iteration. Approximately 940 students have launched over 140 BalloonSats. During this period, only two BalloonSats have been lost during the flight and recovery. Numerous scientific data has been returned and reported. Most teams have done very well during this experience however some have not. It is very important this project and team mission be taken seriously. RFP 2500F08 2

3 General Mission Requirements The following requirements apply to all teams and must be met. A portion of your team grade will be dependent compliance with these requirements. 1. Design shall have one additional experiment that collects science data. (please see suggested experiment topics at the end of this document) 2. After flight, BalloonSat shall be turned in working and ready to fly again. 3. Flight string interface tube shall be a non-metal tube through the center of the BalloonSat and shall be secured to the box so it will not pull through the BalloonSat or interfere with the flight string. See flight string attachment diagram at the end of this document. 4. Internal temperature of the BalloonSat shall remain above 0 C during the flight. 5. Total weight shall not exceed 1,000 grams. 6. Each team shall acquire (not necessarily measure) ascent and descent rates of the flight string. 7. Design shall allow for a HOBO H (provided) 68x48x19 mm and 29 grams 8. Design shall allow for external temperature cable (provided) 9. Design shall allow for an Canon A570IS Digital Camera 45x75x90mm and 220 grams (with Lithium batteries) 10. BalloonSat shall be made of foam core. 11. Parts list and budget shall include spare parts. 12. All BalloonSats shall have contact information written on the outside along with a US Flag. 13. Units shall be in metric. 14. Launch is in November 15, Time and location: 7:30 AM in Windsor, CO. Launch schedule will be given later. Everyone is expected to show up for launch. Only one team member is required to participate on the recovery. Launch and recovery should be completed by 3:00 PM 15. No one shall get hurt. 16. All hardware is the property of the program and must be returned at end of the semester. RFP 2500F08 3

4 17. All parts shall be ordered and paid by Chris Koehler s CU Mastercard by appointment to minimize reimbursement paperwork. All teams shall keep detailed budgets on every purchase and receipts shall be turned in within 48 hours of purchase with team name written on the receipt. 18. All purchases made by team individuals shall have receipts and must be submitted within 60 days of purchase or reimbursement will be subject to income taxes. 19. Have fun and be creative. 20. Absolutely nothing alive will be permitted as payloads, with the exception of yellow jackets, mosquitoes, fire ants, earwigs, roaches, or anything you would squish if you found it in your bed. 21. Completion of final report (extra credit if team video is included) Proposal Instructions Proposals must be typed, 12 point, Times font, 1 inch margins, page number and team name in footer, and project name in header. Proposal must be no less than 7 pages and not exceed 10 pages, including cover sheet and budget. Proposal must include drawings of idea (include dimensions), organization chart with those responsible for each task, functional block diagram, schedule of design, build, and test dates, itemized budget with total, mission statement detailing what you expect to discover. Examples of these items are included in the back of this announcement. Proposal must be written in Microsoft Word (.doc) and shall not exceed 15 MB. Please send proposal via to your instructor by 5:00 PM on September 23, One paper copy must also be turned at the review scheduled on the due date. All pictures, budgets and schedules must be included in the electronic copy. Proposals turned in after deadline will be penalized by 15% to 90% depending on the lateness. There should be very little unknowns in your proposal (i.e. TBD or?). You should estimate or find out as many details as possible. Cover the how and why of your mission in great detail. Avoid weasel words. Do a professional job on the formatting as well. RFP 2500F08 4

5 Proposal Format and Structure An example of the format and structure of your proposal is as follows: Overview and Mission Statement: - State your design concept concisely (Mission Statement) - Explain why you want to do what your team is proposing - Propose what you plan to discover Technical Overview: - Discuss your design - Illustrate your design and how it will work - Discuss the hardware you will need - Discuss how your team will build your concept and who will do what - Discuss how your team will test your design to ensure it meets requirements and objectives - Discuss your launch program - Discuss how you will keep people from getting hurt - Include any special features of your design - Include summary of events your team will perform on launch day including data retrieval and recover of your payload - Include your functional block diagram in this section - Include how you are meeting all the general proposal requirements - Include a weight budget Management and Cost Overview: - Create a detailed schedule which should include these events (Complete design, acquire all hardware, prototyping design, testing final design, cold test, design reviews, other activities described on class syllabus (demos, mission sims), team meetings, etc) - Include organizational chart and indicate each team member s tasks - You should include a brief description of each team member. - Document phone numbers, school, addresses, special skills, etc. - Create a detailed and itemized budget with total - Include a plan on how your team will keep its budget & who ll manage it. RFP 2500F08 5

6 Reporting and Presentation Guidelines Each team shall complete four presentations (Conceptual Design Review (CoDR), Critical Design Review (CDR), Launch Readiness Review (LRR), and Final) and four revisions of their Design Document (Rev A, B, C, and D). The guidelines for each presentation are on the website under Teams/Templates/Presentations. The guidelines for all revisions of the Design Document can be found on the website under Teams/Templates/Design Document. All presentations are due at 8:00 AM on the first day of class presentations. For example, the Final Presentations are held over two class periods. All presentations are due on the first day even if a team is presenting on the second day. All Design Document revisions are due on at 8:00 AM of due date. Times listed on Syllabus and/or discussed in class by the instructor override these times. CoDR Slides Due Design Document Rev A Due CDR Slides Due Design Document Rev B Due Design Document Rev C Due LRR Slides Due Design Document Rev D Due Final Presentations Due RFP 2500F08 6

7 Possible Experiment Ideas Prof. Robert Fesen from Dartmouth College and Dr. Eliot Young from the Southwest Research Institute approached the Colorado Space Grant Consortium in June 2007 about asking the students of the Fall 2008 course to help them with their astrophysics research concept of using high altitude platforms to conduct Hubble-like observations. We had several meetings over the summer and with the help of Dartmouth engineer Dr. Yorke Brown we have come up with the following project ideas. Projects can be taken on by more than one team. Each team will develop their own payload. Robert, Eliot, and Yorke have offered their assistance to teams as they develop their payloads and are willing to supply needed hardware where possible. 1.0 Sky Brightness Measurements 2.0 Video Capture of Stars Using CCD Imaging System 3.0 Stabilized Video Capture of Stars 4.0 Attitude Determination of Instrumentation 5.0 Attitude Determination and Control of Instrumentation 1.0 Sky Brightness Measurements 1.1 How to quantitatively measure sky brightness? Measurements could be made using a photodiode detector. Yorke Brown has provided a reference design for a simple photometer that could be the basis for an appropriate instrument. [ The instrument consists of a small refracting telescope with a photodiode at the focal point of the objective lens. Since the amount of light available for measurement will be very small, the photodiode should be cooled to reduce dark current and dark current noise. Cooling can be achieved by mounting the photodiode to a cold finger extending to a radiator on the top of the vehicle. The photodiode output must be integrated to produce a usable low-noise signal, and the data for both the photocurrent and cold finger temperature must be recorded with accurate time stamping. Development of this instrument will pose several interesting challenges: a. The telescope and thermal management system. b. The electronics for initial processing of the photodiode output and for temperature monitoring. c. The data acquisition system and on-board computer for autonomous system control and data logging. d. A calibration system. The sensitivity of the instrument will depend on details of its implementation and on temperature. 1.2 How does sky brightness changes with altitude? Determine at what altitude the sky luminance stops changing rapidly. That is, what is the minimum practical altitude for a high-altitude astronomical observatory if one wanted to operate it both day and night? Will 65 kft work nearly as well as 80 kft? The winds are lowest at around 65 RFP 2500F08 7

8 kft and increase sharply with increasing altitude making a station-keeping platform harder and the LTA vehicle bigger and more expensive. Of course, higher will be better in terms of sky brightness, but higher altitudes mean bigger vehicles and difficult platform propulsion and energy issues. The challenge in answering this question will be to develop a photometer with sufficient dynamic range to measure the sky luminance as a function of altitude while the vehicle is climbing. 1.3 How does sky brightness change with altitude as a function of wavelength coverage (color)? For example, if we wanted to observe stars, galaxies, planets, etc. during the day, how much better off would we be if we were to restrict our observations to specific wavelength bands? Most astronomical observations are made in specific wavelength bands using standard filters. It would be extremely useful to know what the sky brightness is in those restricted bands, but it would also be useful just to know how different the brightness is between two very broad bands, say below and above about 600 nm. The sensitivity of the photometer depends on the spectral sensitivity of the photodiode, which peaks at about 850 nm, falls off rapidly toward longer (IR) wavelengths and tails off gradually through the visible spectrum at shorter wavelengths. Two or three photometers with different filters could make a valuable distinction. 1.4 How difficult is it to observe during the day given the very bright Earth below? That is, is it easy or hard to eliminate light contamination effects from a high-altitude observing platform? Again, what is the effect if one restricts the observations to the red part of the spectrum? Do such filters make a big difference or is the problem just too hard to begin with? Pointing away from the Sun will be critical for this experiment. 2.0 Video Capture of Stars Using CCD Imaging System 2.1 Can stars be captured using a CCD Imaging System? One of the best selling tools for gaining funding for a high-altitude, station-keeping balloon platform would be a video showing stars including rather faint ones gradually becoming visible during a high-altitude balloon flight in early daytime conditions when the payload reaches altitudes of 65 kft and more. A video showing the emergence of stars as the payload goes up would make the point very nicely that optical astronomical observation can be performed off a balloon platform. Miniature CCD video cameras suitable for making such a video are readily available. Certainly one challenge to recording a video is the length of the flight. How should the data be stored? Should the camera record continually, or in relatively short bursts? Should the data be stored digitally by an on-board computer, or on tape? Would it be feasible to make an effective time-lapse video of the entire ascent? RFP 2500F08 8

9 Although a natural color video would have appeal, it would be more scientifically valuable to record scenes monochromatically through the same filters as were used on the sky brightness photometer. Will a red filter improve contrast without too much of a penalty in sensitivity? Can a camera with a red filters see stars well at night from a dark site in Boulder? How much better do the stars show up in the video with no filters? If more sensitivity is required, can the team design a method of fitting a larger aperture lens? 3.0 Stabilized Video Capture of Stars 3.1 Is it possible to stabilize the CCD Imaging System during the flight? Balloon payloads tend to swing and spin on the string, posing an obvious challenge for photography. It may be possible to stabilize the camera inside the vehicle by mounting it on an inertial gimbal (like the famous Steadicam used in Hollywood). Perhaps a small gyroscopic stabilization system would be even more effective at lower weight and volume. Are there other possibilities for vehicle stabilization? Would a trio of electric motors mounted at right angles gyroscopically stabilize a vehicle? Is there a simple way of stabilizing the whole string? 4.0 Attitude Determination of Instrumentation 4.1 Where the heck is the payload pointing? If stars are visible, one would of course like to know what direction the camera was pointing. What stars and constellations were detected? For sky brightness measurements, keeping the instrument free from stray sunlight and Earth glow is critical. Possibly the easiest way to measure attitude is with a three-axis magnetoresistive magnetometer detecting the Earth s magnetic field. 5.0 Attitude Determination and Control of Instrumentation 5.1 Is it possible to change the pointing of the payload during flight? After determining the pointing direction of the payload, can a system be developed to rotate the payload or the instrument on the flight string toward a different direction? Can a system be developed that would maintain a specific pointing direction for an instrument throughout the flight? Perhaps the magnetometer signal could be servoed to a set azimuth using an inertial wheel with a vertical axis. RFP 2500F08 9

10 BalloonSat Attachment to Flight String RFP 2500F08 10

11 Example Functional Diagram Heater Power Timer Power Dual Pole Switch Timer Heater 1 (To Heater 2) (To Heater 3) Camera 1 Power Camera 1 Camera 2 Power Pull tab Camera 2 RFP 2500F08 11

12 RALPH Functional Block Diagram External Temp Switch HOBO datalogger Internal Temp Humidity 9V Battery 9V Battery 9V Battery Switch Heater Pen-cam heater Pen-Cam ELPH Cam Video-Cam Servos BASIC stamp 9V Battery 3V Battery Switch 3V Battery 9V Battery RFP 2500F08 12

13 Power (Batteries) BASIC stamp Switch 3 Photo Diode w/ Visible Light Filter Switch 1 Power (Batteries) Photo Diode w/ Infrared filter Photo Diode w/ both filters Infrared Camera Heater HOBO Film Camera Timing Circuit Switch 2 Power (Batteries) Example Drawings RFP 2500F08 13

14 RFP 2500F08 14

15 Mission Statement Examples: The BalloonSat Aquintus shall ascend to an altitude of approximately 100,000 feet to carry out scientific experiments that will measure tilt of the satellite, forces acting upon it, wind speed, and solar energy to better understand the conditions in which high altitude observatories would be in. To provide research support for a low Earth orbit telescope platform by showing the emergence of stars as a BalloonSat ascends to 100,000 feet and provide dark current values to provide information about energy use on the platform. The primary mission of Teamo Supremo s balloon satellite is to ascertain at what altitude stars become visible through the use of a CCD video camera fitted with an infrared filter. RFP 2500F08 15