STITCH
BalloonSat Proposal
Team: TBA
Team Members: Quinn Kostelecky, Roshan Misra, Jacquie Godina, Vincent Staverosky, Ray Auyeung, Gloria Chen
ASEN 2500
University of Colorado at Boulder
Professor: Christopher Koehler
September 18, 2011
MISSION STATEMENT
The BalloonSat “STITCH” will rise to an altitude of 100,000 feet, in order to complete our mission. The mission is to utilize this satellite to take measurements of the magnitude of electromagnetic field waves at various altitudes. In addition, we will be measuring the voltage produced by the aforementioned EM fieldwaves.
MISSION OBJECTIVES
- Construct a complete BalloonSat by 11/03/11 that will survive a flight to 100,000 feet and back.
- Measure the magnitude of electromagnetic field waves at various altitudes using a magnetometer.
- Measure the amount of voltage produced by the EM waves using a voltage sensor.
- Take pictures of the horizon of the earth using a camera on board the BalloonSat.
MISSION OVERVIEW
Our mission was chosen for four main reasons: to see if voltage generated by the change in magnetic fields could potentially be used as a backup energy source to power satellites, spacecraft, and/or other technologies in space; to see how magnetic fields differ at different altitudes. The data can also be used to studyhow they may interfere with electronics with minimum shielding at these altitudes, and we will also test the feasibility and practical applications of “free energy”. Some free energy enthusiasts are adamant that there is a way to generate electrical power by harnessing the Earth’s magnetic field. We will either prove or disprove this theory. Another aspect of our experiment is to take pictures while in near space for a qualitative measure of where our satellite had been.
As stated by Faraday’s law, a change in magnetic environment in a coil of wire, no matter how small, will generate a voltage. The magnetic fields of Earth change while altitude increases, meaning that we can test the voltage generated if we send a voltage sensor connected to a solenoid into near-space onboard our satellite. On future space missions, if this magnetic field power supplies a fair amount of voltage, then future spacecraft and satellite missions can use this as a back-up or supplementary power source instead of heavy and costly batteries.
In addition to the voltage experiment we will also measure the actual magnitude of the magnetic fields using a magnetometer. This will give us insight into how electronics with minimum shielding will react to the magnetic fields at various altitudes around Earth.We can compare this with ourcurrent readings and temperature readings to gain even more insight into the behavior of these electromagnetic fields. This will also help us to determine how much shielding we would need to supply to electronics on aircraft and satellites in order to prevent all forms of magnetic interference.
We chose this mission because we are all intrigued by this idea of possible free energy. In addition to our interest in the project, the experiments are something we know very little about and we’re excited to learn new things. The project will take some programming and this entire experiment will be a very challenging task.
TECHNICAL OVERVIEW
Structures
The structure of our BalloonSat “STITCH” is going to be in the shape of a cube. The structure will be 18 cm. long by 18 cm. wide by 18 cm. deep. The cube will be held together using aluminum tape and hot glue to improve the structural integrity. We are assuming our actual volume of our cube will be 3,375 cm3 assuming 1.5cm for the thickness of the foam core. This is a rough estimate, and we will revise this measurement later on. We will cut a hole near the corner our camera is in for the lens of the camera to take pictures through. This hole will need to be a fairly tight squeeze for the lens so as to reduce loss of heat because there will be no seal on the hole. We will have a flight tube running through the center of the satellite and attach a flight cord to it in order to reach our target altitude of 100,000 ft. We will use foam core strips to brace our camera into the corner of the satellite. In addition to the foam core we will use one centimeter thick insulation on the inside of the satellite in addition to the heater to keep our satellite’s internal temperature above -10oC.
Data Storage
For our primary datalogging, we will be using a HOBO H08-004-02 Datalogger and an Arduino Pro 328. Our HOBO will be recording data of the external temperature, internal temperature, and inside relative humidity. The Arduino will be logging the data of our magnetometer and current sensors. We will program our HOBO and Arduino to timestamp their data so that we can compare it with the readings from our GPS signal in order to determine the magnetic field intensity as a function of altitude. We will also use the converted readings from our current sensor to determine the voltage as a function of magnetic field intensity. Because the HOBO seems to have a relatively long battery life we should not have to program the HOBO for logging delays.
Experimental Subsystems
Magnetometer
In order to measure the strength of the Earth’s magnetic field, a MicroMag 3-Axis Magnetometer will be placed onboard the BalloonSat. The data output will go to an Arduino microcontroller which will store the data on a memory card along with the time at which the data was recorded. This will be done by programming the Arduino to timestamp the data it acquires from both the current sensor and the magnetometer. This information can then be compared with the GPS altitude readings (provided by Gateway to Space) to plot the magnetic field strength as a function of altitude.
Solenoid and Current
One of our mission goals is to test the availability of energy from the Earth’s magnetic field. We will go about testing that by applying Faraday’s Law to generate and measure voltage in a closed loop. In order to amplify the induced electromotive force (emf) from the magnetic field, a solenoid which essentially multiplies the induced emf by a factor of the number of wraps of the solenoid, will be used. This solenoid will be made by simply wrapping insulated copper wire as many times as possible around the largest area possible that we can create with a length of 11 cm. and that will still not exceed the weight restrictions. The current driven by that emf will be measured by a current sensor, recorded, and timestamped by the Arduino. With the current, the voltage induced can easily be calculated with Ohm’s Law. This current will be affected by the temperature as well because the average resistance of the solenoid will be less at colder temperatures. Since that information is timestamped, it can be compared with the magnetic field strength, altitude, and temperature readings. That data will allow us to consider the effects or temperature and field strength on the voltage produced as well as how feasible this system of acquiring power would be for other applications.
Camera
In order to take clear and high quality pictures, we will use a Canon A570IS Digital Camera on our BalloonSat. It will be secured in an exterior corner of the satellite facing horizontally to capture pictures of the horizon. For stability, the camera will be held against the wall with strips of foam core so it will not move around during flight. No glass or Plexiglas window will be used to shield the camera due to potential condensation on the shield. The software of the camera will be modified to take pictures every ten seconds automatically during flight, and store these images on a memory card. Power will be supplied to the camera by two AA Lithium batteries. To ensure proper operating temperatures, a heater, in addition to the insulation, will be onboard the BalloonSat which will keep interior temperatures above -10oCelsius. Foam core support for the camera will not completely encase it to allow proper temperature regulation.
Heater
In order to keep our satellite at a reasonable temperature for operating the experiments, we will be using a heater that is supplied to us in class. This heater requires two nine-volt batteries which will be placed against an inside wall of our structure. The heater will be placed in the center of the satellite next to the flight tube. This heater, in conjunction with the insulation inside of our foam-core structure will prevent the internal temperature from dropping below -10oCelsius.
DATA RETRIEVAL
Possibly the most crucial aspect of the entire mission is data retrieval. Without an effective means of collecting the information we record during flight, no conclusions can be drawn from our experiments and thus the whole mission would be a failure. To complete such a critical task, we are keeping to the KISS (Keep it Simple Stupid) principal. Data for the camera will be recorded on the 2GB memory card (supplied by Gateway to Space). Data from the magnetometer and the current sensor will be recorded on an Arduino microcontroller programmed to timestamp the data and store it on a microSD card. The HOBO will store data for the temperature (internal and external) and the relative humidity. The camera, HOBO, and the Arduino card will all easily connect to a computer after retrieval of the BalloonSat. When all the data is transferred to a computer, we can compile all the data based on when it is recorded (due to the programming of our Arduino and HOBO) and compare the altitude, time, temperature, magnetic field strength, and induced electromotive force (emf) to check for any correlations.
TESTING
The Drop Test
The first half of the drop test is to test the strength of the structure of the BalloonSat by dropping it from a second story ledge. This will allow us to see if the structure is strong enough to withstand the impact of landing and the forces it will undergo during burst. The second half of the drop test is to roll the structure down a flight of stairs. During this test we will be able to see if our structure can withstand the rolling andturning that the BalloonSat might experience during burst and landing.
The Whip Test
The whip test will involve the attachment of a string to the structure. The tester will swing the structure around above their head and body to simulate the burst of the balloon because when the balloon bursts, it will exert a great amount of force on our structure. This will ensure that our structure will not fall apart under these conditions.
Cooler Test:
Since the satellite will go through a section of its flight in extremely cold temperatures, we need to make sure that all of our equipment will still work under those temperatures and make sure that the insulation and heater keep the internal temperature above -10o Celsius. To do this, we will place our structure into a cooler filled with dry ice for 135 minutes (the approximate amount of time the satellite will be in the air).
The Sensor Tests
Current Sensor-The solenoid power circuit is a very important part of our mission and it is necessary to fully understand how it will work during our mission. When we have successfully hooked the solenoid to our voltage sensor and Arduino, we will test the solenoid’s capability of setting up a voltage in the circuit with a magnet. We will pass the magnet through the solenoid, rotate the solenoid, and try various other relative motions to see potential voltage levels we will need to record in the mission. This will also allow us to test our ability to record the reading from the voltage sensor with the Arduino.
HOBO and Arduino-We will test the HOBO and Arudino’s measuring capabilities and our ability to record and recover the data measured by them prior to launch. This will also guarantee that we have correctly programmed our equipment for our purposes. We will do this by measuring the temperature that is already known so we can make changes to ensure accurate temperature measurement during the mission.
Magnetometer- It is critical to calibrate and test the magnetometer prior to flight to ensure that accurate and relevant data is collected during the mission. The magnetometer will be zeroed with no electronics or magnets in close proximity (except those running it) and a magnet of known strength will be brought near it to test its measurement. Zeroing the magnetometer at ground level will mean that we have a reference point of the Earth’s magnetic field strength with which we can compare our altitude data against to see relative gains or losses in magnetic field strength with altitude. At this time we can also test our ability to store, recover, and compile data with the Arduino. We will also take a baseline reading during our full-length flight simulation of the magnetic fields created by the hardware running on the satellite. This will help us filter out interference so we can more effectively measure the Earth’s magnetic field strength.
Full Mission Simulation
After all other tests are completed, a full-length mission simulation will be run to check that all systems are working together properly without errors. This will be done well before the launch date in order to allow for time to fix any potential problems.
HARDWARE LIST, BUDGET, AND WEIGHT SUMMARY
Hardware, Budget, and Weight ListItem / Cost ($) / Weight (g) / Supplier
MicroMag 3-Axis Magnetometer / 49.95 / ~10 / Sparkfun
ACS712 Low Current Sensor Breakout / 14.95 / ~10 / Sparkfun
HOBO H08-004-02 / 0 / 30 / Gateway to Space
Canon SD780 IS / 0 / 130 / Gateway to Space
Active Heater System (With 2 9V Batteries) / 0 / 100 / Gateway to Space
Arduino Pro 328 / 19.95 / ~30 / Sparkfun
36 Ga. Copper Wire to make Solenoid / 12.66 / ~100 / Home Depot
Switches / 0 / ~2 / Gateway to Space
Flight String Tube / 0 / ~20 / Gateway to Space
Batteries (12 9V only one will fly) / 20 / 14 / Target
Batteries (6 AA for testing) / 0 / N/A / Quinn Kostelecky
Foam Core / 0 / ~300 / Gateway to Space
Alluminum Tape / 0 / ~10 / Gateway to Space
Dry Ice (for cold test) / 10 / N/A / King Soopers
Memory Card for Arduino / 0 / 0.5 / Ray Auyeung
Magnet for testing / 0 / N/A / Roshan Misra
Total / 127.51 / 756.5
Remaining Balance / 122.49 / 93.5
In order to stay within our budget, our team has selected supplies that are within our limits but can still supply us with what is necessary to complete our science mission. This means that we had to look around for the provider that has the best deal. Another way in which we can stay within our budget is to make sure that we are only buying the necessary things.
DESIGN DRAWINGS
HOW WE WILL MAKE THIS AN ACTUAL SATELLITE
Our satellite will be built in the form of the structure described and shown above. The satellite will have the camera placed in a corner and braced against the corner with lens facing outwards to picture the horizon of the earth. Our camera has had its firmware modified to take pictures at a rate of one picture/10 seconds. The heater will be spaced approximately 3cm away from the camera, close to the center of the actual satellite. Our magnetometer will be placed away from the batteries and solenoid in order to reduce the magnetic fields given off by the electronics and to prevent detection by the magnetometer. The current sensor and solenoid will be placed close to each other to isolate the system and to allow for as much efficient usage of space. The HOBO will be placed against the wall next to the heater and Arduino and the temperature probe will be fed through a small hole to prevent the loss of heat from the satellite as much as possible. The HOBO and the Arduino Pro will be programmed to timestamp the data it retrieves from the magnetometer and current sensor so that we can compare it with our other data to draw correlations between all of our data. External switches, along with an external LED, will be placed on the outside of our satellite to allow us to switch on the experimental subsystems without actually having to open up the satellite. The LED will be wired to indicate that the experiments are running.
HOW WE WILL KEEP PEOPLE FROM GETTING HURT
In order to prevent injuries from occurring during this project, there are several precautions we will take. When we are building the structure, we will make sure that everyone handling dangerous equipment, such as exact-o knives or power tools, will keep them pointed away from all members, including themselves. Everyone soldering will be wearing safety goggles and make sure that the soldering iron is always in its stand when not in use. While performing the tests on the structure, make sure no one but the tester is nearby so that they won’t get injured while the tests are in progress. Before every test, the tester will start a countdown from 10 to 1 and then the test will commence. This will ensure that everyone on the team will be ready for the tests to start and be aware of when the tests are started. During the cooler test, the person handling our satellite will wear gloves so they do not get frostbite from the dry ice. During tests like the whip test and drop test, we will make sure no one is within 10 meters of the pathway of the structure so that it or possible debris, does not hit anyone. We will make sure to keep watch for all passersby during the tests. In addition to this we will make sure that during all building and testing there will be at least two people present in order to prevent mistakes during these activities.
FUNCTIONAL BLOCK DIAGRAMS