2014 Project SMART/Space ScienceHigh Altitude Balloon Flight to The Edge of Space

At an altitude of 100,000 feet (30,000 meters) 99% of the Earth's atmosphere is below and the environment begins to take on properties of space.

At this 'edge of space' region, the air pressure is only 10 millibar, the temperature is -70 to -100 degrees Celsius, and radiation is significantly high.

With less than 1% of the atmosphere above, the sky is 'space black' and the view of the Earth shows a curvature.

The SMART Space Science group built and flew a high altitude balloon system to test a parachute free ‘re-entry’ shape, measure characteristics of the payload, test new flight hardware and techniques and take video near the ‘edge of space’.

SMARTSat uses a non-parachute flight frame designed around a flat conical shape with a large surface area, low weight, a high drag coefficient and low center of gravity.

The balloon system uses amateur (HAM) radio and GPS for tracking and control.

All flight parameters comply to FAA regulations (FAR 101)

Sarah Coffen, John Gadbois, Uri Hall, Estarlyn Hiraldo, Gary Hu, Madeline Hubbard, Brandor Matos, Nick Payne, Victor Pierre, Shaafi Sabir, Matthew Shindel, Jared Spang, Dr. Chuck Smith, Rich Levergood, Scott Goelzer, Lou Broad

Standard Balloon SystemWith parachute.

Photos courtesy of Devin Thomas

Flight Objectives:Fly and recover the balloon system Evaluate flight stability of the reentry vehicle designTest computer systemsTest line cut/release systemsObtain high resolution video of the flightVerify reliability of flight prediction software– Test 5 independent flight experiments– Radiation in upper atmosphere– Temperature characteristics of the payload– Temperature characteristics of the cameras– Sun angle sensor– IR and UV photometer

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Flight Profile SMARTSat VII

Altitude vs. Time

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SMARTSat Balloon SystemWith re-entry design

SMARTSat VIII provided the sixth opportunity to test the parachute free flight frame. The use of parachutes in ballooning is obvious as they allow any payload to return to the ground undamaged. Previous experience showed that parachutes can fail in deployment or become wrapped into the flight boxes.

UNH/Project SMART along with three cooperating local high schools, developed a flight frame design that does not use a parachute, but rather uses a lightweight high drag saucer shaped vehicle made from conventional construction foam.

The flight frame also provides greater options for mounting equipment, a single line attachment to the balloon that allows for superior ‘cut-down’ design and superior balancing options.

The SMARTSat VIII used an improved flight computer system that allowed for 5 independent flight experiments built and operated by SMART students.

The balloon was launched from UNH, ascended at approximately 1000 feet per minute reached an altitude of 97600 feet and landed north of Lewiston Maine

Instrument Bay Temperature Instrument bay temperature was compared to outside temperature. The protected instrument bay maintained a temperature about 20 degrees (C) higher than the outside environment. Temperature decreased with altitude, until the craft entered the stratosphere. The loss of convective cooling allowed internal heat to build until maximum altitude. On descent slight pressure difference between inside and outside caused super cooled air to 'ingas' until the craft re-enters the troposphere. The thermistors likely 'bottomed out' at 255K

Entering Stratosphere

Re-enter Troposphere

Camera bay temperature for Cannon A810 and GoPro was measured to determine if they fly in a sufficiently protected environment. Temperature profiles followed the same trends as the instrument bay temperature experiment. Indications are that the temperatures in both experiments went well below optimum operation conditions This will drive modifications for future flights.

Camera Bays Temperature

Student Experiments

Cannon camera (purple)

GoPro Camera (blue)

Radio interference (ignore)

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Radiation in the Upper Atmosphere

A improved version of the Cannon Hack system (CHDK), was installed into a Cannon A810 Powershot camera and operated allowing for high detail photos taken every 2 seconds throughout the flight. Over 8000 photos, including 2 and 1/2 hours of grass growing at the landing sight, provided an exceptional record of the flight. Photo 8877, at 33000 feet on the descent, shows an unidentified anomaly.

Improved Camera Systems Radiation was measured using a Geiger counter taking total counts vs. mission elapsed time.The Pfotzer maximum, the point where secondary radiation reaches peak, is viable in two places on the graph as the balloon passed through on ascent and again on descent.

Sun Angle Sensor A Sun Sensor

measured light intensity in the atmosphere that is emitted from the sun to determine craft orientation to the sun. The Sun Sensor measures light intensity by using Cadmium Sulfide (CdS) photo resistors on 4 angles of the platform.

Future application would allow for the on board computer to manage camera operation based on sun angle.

IR and UV Photometer Experimental IR and UV Photometers were made using LEDs that are sensitive to those bands. This proof of concept mission will allow for more complex multichannel (up to 32 channels) photometers to be flown in future flights.

Pfotzer Maximum at ~80000 feet

Photo 8877 Unidentified Anomaly at 33,000 feet

The flight modeling software (available on-line from HABHUB) provided a perfect prediction of SMARTSat's flight.

Ascent rate was consistent at 5.1m/s

The descent rate, at touchdown, was 8.8 m/s.

Maximum altitude 97,000 feet