Undergraduate Space Research Symposium University of Colorado Boulder HASP HELIOS II 2013 Undergraduate Space Research Symposium University of Colorado Boulder Presenters: Caleb Lipscomb and Jon Sobol

High Altitude Student Platform (HASP) Supported by the NASA Balloon Program Office (BPO), run by LSU Max Altitude: approx. 36km 15 to 20 hours of flight time 11 million cubic foot helium Balloon 12 Student Payloads 8 small 3 kg payloads 4 large 20 kg payload HELIOS II, Large payload University of Colorado Boulder

Current Solar Observation Orbital Platforms Expensive to develop and launch into space, cost limits access. Advanced Composition Explorer (ACE) – $106.8 Million Solar and Hemispheric Observatory (SOHO) - $1.05 Billion Ground Based Face interference from the atmosphere, lowering the quality of the images High Altitude Balloons Low Cost Ascended above 99.5% of atmosphere University of Colorado Boulder

Hydrogen-Alpha Exploration with Light Intensity Observation System (HELIOS II) Mission Objectives: Observe and capture images of the Sun in Hydrogen Alpha wavelength and to identify sun spots in those images. Design and implement a system to locate the Sun in the sky and orient cameras towards the sun. Prove the viability of high altitude balloon solar observation during a Colorado Space Grant Consortium (COSGC) sponsored HASP flight. University of Colorado Boulder

Hydrogen Alpha Sun Spots 656.28 nm Mid Chromosphere of the Sun In visible light range Mid Chromosphere of the Sun Average Sunspots: 10,000 km to 50,000 km in diameter Solar Cycle max University of Colorado Boulder

HELIOS II Design Attitude Determination and Control System (ADCS) Solar Wavelength Imaging System (SWIS) Electronic Power System (EPS) Command and Data Handling (C&DH) Structure and Thermal University of Colorado Boulder

Solar Wavelength Imaging System (SWIS) 2 cameras Science Camera - Identify Sun Spots ADCS Camera - Characterize performance of Attitude Determination and Control System (ADCS) Imaging Source “51”Series CCD Cameras 1600 x 1200 pixel CCD chip Hydrogen Alpha filtration system University of Colorado Boulder

Science Camera Magnification 2 Lenses Fov: Vertical ϕ Axis: 1.56° or 1° 33’ 30.1” Horizontal θ Axis: 2.08° or 2° 4’ 40.1” University of Colorado Boulder

ADCS Camera Magnification 1 Lens Fov: Vertical ϕ Axis: 15.5° Horizontal θ Axis: 20.1° University of Colorado Boulder

Filtration System 400 nm Dichroic Longpass Filter (UV filter) Hot Mirror (IR filter) Neutral Density Filters Narrow Bandpass Filter (Hydrogen Alpha) 656 nm, 10 nm bandwidth University of Colorado Boulder

Science Camera: Expected Results Picture: 1600 px by 1200 px University of Colorado Boulder

Sun: approx 417px in diameter 10,000 km: 3 px in diameter 1 px: approx. 3333 km University of Colorado Boulder

Electrical and Computing Housing Structure Overview Photodiodes ADCS SWIS Electrical and Computing Housing Aluminum Frame Mounting Plate Triangular Trusses University of Colorado Boulder 13

HASP Interface 14.9 University of Colorado Boulder

Thermal Motor drivers and CPU to be heat sinked to outer aluminum structure Entire platform to be painted white Higher emissivity No reflective interference Excess aluminum to be used in the electrical and computer housing structure to dissipate heat University of Colorado Boulder

Electrical and Power Systems (EPS) Power Provided by HASP Platform EDAC 512 connector 30 Volts at 2.5 Amps Converts HASP power to power required by payload systems Arduino Due Monitor current and voltage MOSFETs University of Colorado Boulder

Circuit Diagram University of Colorado Boulder

Command and Data Handling (C&DH)

Overview Discrete Commands: Main Computer – Pandaboard Communication between subsystems Store images Solid State Drive Environmental Sensors: Accelerometer Pressure Sensor Thermocouples Signal relay: MUX Analog to digital converter Health and Status Downlink Command Action Power ON Activates power to HELIOS II payload Power OFF Terminates power to HELIOS II payload Reset ADCS Restarts the ADCS command algorithm, used to trouble shoot in flight ADCS issues University of Colorado Boulder

Communication ADCS Digital signal to Pandaboard confirming orientation Digital signal to ADCS to start orienting HASP Platform Pandaboard Temperature sensors Ground Station Picture sent to Pandaboard thereby informing it to signal ADCS to start orienting Digital signal to SWIS to take picture SWIS University of Colorado Boulder

Attitude Determination and Control System (ADCS) 2 Motors Arduino DUE 2 Photodiode Arrays Theta (Θ) Array Phi (Φ) Array Theta (Θ) Array Phi (Φ) Array Phi Motor Theta Motor

Arrays Theta (𝜃) Photo Diode Array Phi (Φ) Photo Diode Array 3D Printed at ITLL Made out of Nylon/Acrylic Composite Theta sensor has 14 photodiodes and Phi Sensor has 6. Designed for modularity and ease of access University of Colorado Boulder

System and Controls Overview University of Colorado Boulder

ADCS Orientation Process C&DH sends ADCS command to reorient. ADCS collects Theta Plane photodiode readings ADCS centers to highest intensity source ADCS collects phi plane photodiode readings. ADCS centers to highest intensity source on phi plane ADCS retakes theta plane readings and reorients. ADCS initiates Symmetry Test ADCS sends command to C&DH that orientation has been completed. C&DH sends command to SWIS to capture an image University of Colorado Boulder

Concept of Operations Altitude Flight Timeline Day Float Night Float Descent Landing Launch Ascent 36 km Altitude T 0 hrs Launch- System powered off T 2 hrs Float Altitude- Power on and check H+S of all systems T 2.5 hrs Begin Mission Operations T 10 hrs Power off Payload T 20 Begin Descent T 22 hrs HASP Platform Lands University of Colorado Boulder

System Initialization Procedures 2. EPS activates power to Pandaboard. Pandaboard reports initial health and status to ground 1. Discrete Cmd given by ground station to power on HELIOS II 3. EPS powers on ADCS, ADCS reports H+S to Pandaboard 4. Discrete command ADCS to begin operations 5. Run mission operations: track sun & capture images University of Colorado Boulder

Flight and Results Current Flight date: August 26 Identify at least one sun spot Observe same sun spot in 3 separate pictures ADCS success: Observe sun in 10% of Science camera images Exact performance characterized by ADCS camera Prove viability of high altitude balloon observatories University of Colorado Boulder

Questions? University of Colorado Boulder