SUNSAT Farita Tasnim Shivani Upadhayay Jinny van Doorn

Merit Review Big Picture Questions What is the intellectual merit of the proposed activity? What are the broader impacts of the proposed activity? Is student training used in this activity? Feasibility Review will include questions on technical feasibility, management plan, and education plan. Taken from NSF Merit Review Criteria (January 2013)

FIRST PRIORITY

Flux Gate Magnetometer

Problem 1: Falling Out of NASA Permalloy-Core FGM’s Reference: NASA Proposal No S Proposal Title: Bulk metallic glass for low noise fluxgate NASA is currently experiencing diminishing supply of fluxgate magnetometer ring cores; they are in need of a finer, lower noise core Prime Photonics is developing a cobalt-rich metallic glass for NASA’s use There is a need to test the feasibility of these cores for NASA’s future use of fluxgates. Solution: We are building a fluxgate magnetometers and plan to test the metglass (amorphous metal) core against a traditional permalloy core for evaluation of the core feasibility/performance in space.

Problem 2: Commercial Sensors Lack Precision, Accuracy, and Reliability Reference: Filipski & Abdullah 2006, Nanosatellite Navigation with the WMM2005 Geomagnetic Field Model Currently available commercial sensors have low resolution problems: The best ones have 4 nT resolution, which lacks precise measurement of subtle changes in the magnetic field cause by solar winds There is a need to develop a high quality magnetometer sensor circuit in order to accurately detect the effects of solar winds and IMF interactions with the Earth’s magnetosphere Solution: We are developing a high-precision, closed loop, low power sensor circuit to detect magnetic fluctuations to sub-nanoTesla accuracy Version 1 of this circuit has been developed and will fly on DREAMS Launch 24

Gravity Gradient

Problem 1: Lack of Successful Stabilization in a Cube Satellite/Disturbances Reference: The Johns Hopkins University Applied Physics Laboratory Article Title: FLEXIBLE BOOMS, MOMENTUM WHEELS, AND SUBTLE GRAVITY GRADIENT INSTABILITIES Combination of forces associated with the initiation of the launch significantly affect success of maintaining the attitude of the satellite and have failed in even successful satellites Internal vibration, spacecraft spinning during launch, and weak anchorage of booms contribute to degraded performance Solution: Increase rigidity of systems with stronger boom materials (beryllium- copper rod) that balance the payload (pitch and roll configuration), incorporate reaction wheels/inertia wheels to stabilize third (yaw axis), and place a damper to dissipate extra energy/movement

Dampers (Placed in Center of Mass) A contained fluidic system with the ability to absorb force during impacts and dissipate it as heat to avoid conflict with data detection with cube satellite Should be designed to have a high damping to weight ratio of cube satellite Types: 1. Rod Dampers (most reliable due to simplicity) 2. Spherical Dampers (magnetically coupled to Earth’s magnetic field) 3. Ball-in-Tube Dampers (single-axis) Rods, especially permeable ones, aid in removal of spin energy initiated by launch via hysteresis losses and eddy current development

Problem 2: Magnetic Contamination & Thermal Influence Difficult to avoid: Small magnetic chips, washers, etc. can unbalance the dampers and cause failure Destabilization can be caused by magnetic dipole interaction with the magnetic field. Even if there is a charge distribution along the yaw axis, it factors into external disturbances and forces Even structurally sound boom designs suffer due to thermally induced vibrations Solution: Implementing different actuators (ex: control moment gyro) allows a constant angular velocity to occur on the perpendicular axis, allowing control of spacecraft; minimize the amount of magnetic material within the satellite; use thermal fillers to improve thermal coupling at select locations while thermal washers can reduce thermal coupling at select locations

Benefits Control of electrical power generating capability of solar cells mounted on the satellite Control of the satellite’s thermal balance Directional control of satellite receiving or transmitting antennas Ability to perform scientific experiments to determine the directional properties of charged particles and other radiation which is present in the magnetic and gravitational fields of the earth Ability to determine directional properties of particles that are geo-magnetically trapped in Van Allen radiation belts (i.e. solar winds)

Location-Stamped Data Collection

Problem: Correlating Data to Location of Data Collection Collecting data from satellites and correlating it accurately to the location at which it was gathered is an issue for CubeSats. There is a need to determine accurately the location at which certain data was collected, especially for determining the effect of solar wind on the earth’s magnetosphere. Solution: We are setting up a APRS digipeater on the Sat to communicate with ground stations on the earth, making use of a highly used network of Ham Radio users. That way, data we collect can be accurately location-stamped.

HAB-Augmented Data Collection

Problem: Non-Reliable Short Timespan of Data Retrieval from CubeSat Data for CubeSats traditionally are retrieved as the Sat passes over the home base for a timespan of 5-7 minutes for LEO satellites For Sat’s with high density of sensor data logging or image logging, it is important to be able to transfer large amounts of data to the home base for higher collection of the data gathered There is a need to increase the timespan of homebase data retrieval to secure more of the data. Solution: Our Columbus Space Program has experience with 24 high altitude balloon missions and could send weekly payloads to directly serve the purpose of receiving data from our Sat as it passes over. As these balloons reach the stratosphere, they have increased timespan, estimated at 20 – 30 minutes for data retrieval, so about 4-6x the amount of data can be transferred

Problem: Short Time of Float for Traditional HAB’s High altitude balloons, especially those made of latex burst about two hours after launch, and don’t travel very far It would be helpful to have a balloon that can last longer in the atmosphere and travel around the earth There is a need to increase the timespan of this extended-homebase telemetry data retrieval balloon Solution: We will use stronger, mylar balloons that have been proven to circumnavigate the globe. Though at a lower level in the atmosphere, circumnavigation will increase even further the amount of data that can be collected from SunSat Proof:

Supercapacitors

Problem: Lack of Power Storage Longevity With Batteries Reference: Shimizu & Underwood 2013 The feasibility of supercapacitors for CubeSat applications was analyzed and simulations were run to determine their potential usefulness. Simulations of solar eclipse conditions were run to determine the effect of maximum strain on supercapacitor discharge The result of the study was that supercapacitors provide a lighter mass, more efficient energy storage, and support for higher-power payloads There is a need to test the performance of supercapacitors on CubeSats in orbit. Solution: We are incorporating a hybrid supercapacitor-battery setup and recording data on the charge and current to determine the usefulness of supercapacitors for satellite missions

Education

Problem: The lack of real world experience and project-based learning in STEM for pre- university students Reference: US Congress Joint Economics Committee, 2012, Hixson et. al For young people, there are inadequate hands-on activities in the classroom to pique interest [in STEM fields] Students learning through project-based learning have a deeper understanding of what they are learning and demonstrate better problem-solving skills in PBL than in more traditional classes; they are able to apply what they learn to real-life situations There is a need to enhance and supplement classroom information with hands-on, real-world project-based learning Solution: In addition in to extensively involving high school students in the development of the Sat, outreach to middle and elementary students will communicate the intent of the project and involve them in data collection

SECONDARY PRIORITY

Hydrogen Sensor

Problem: Uncertainties regarding atmospheric H2 gas escape References: Haoshang, Wang, & Hu 2012, Catling and Zuhnile, 2009, UCL 2013 There is no established quantity of molecular and atomic hydrogen, earth’s primary escaping atmospheric moiety, at altitudes approaching 160 km at LEO. Much is unknown regarding the relationship between the escape of atomic hydrogen with solar wind and magnetic field lines Hydrogen gas in space is a key component of the Bussard Ramjet vehicle Escape rates of various moieties such as H2 from planets determine atmospheric properties, and whether or not they can support life Field effect transistors have been flown in CubeSat as radiation and power level sensors There is a need to further explore the escape rate of hydrogen and its relationship to solar wind and magnetic field lines, as well as the fidelity of FET sensing technology. A palladium field effect transistor hydrogen sensor—low-power and compact—will be flown in order to determine if escaping hydrogen can be detected in LEO at levels below 1 ppm.

Sunspot Detection

Problem: Irradiance Study and Solar Storm Prediction Need to be Accessible Reference: Department of Electronic Imaging and Media Communications; University of Bradford, Richmond Article Title: Automated McIntosh-Based Classification of Sunspot Groups Using MDI Images Updating on solar data can help lead new space missions in protected or critical locations Sunspot detection is a collection of data analysis from specialized cameras and imagining to zero in on sunspot locations; reduction in magnetic field or excessive acoustic wave production constitute potential sunspot location Solution: use a regular high-resolution digital camera to find irregularities in color spectrum and also use a Doppler-gram which senses surface velocity of the Sun, indicating a red shift (longer wavelength, farther away) or a blue shift (shorter wavelength, closer to us); in addition, ability to hear acoustic waves ensures accuracy

Sun Orientation