CricketSat Flight CricketSat Flight ProceduresProcedures

Mike Fortney Mike Fortney

University of VermontUniversity of Vermont

Flight Preparation StepsFlight Preparation Steps

• CricketSat flight systemCricketSat flight system

• Flight system materialsFlight system materials

• Prepare CricketSat sensorPrepare CricketSat sensor

• Attach parachuteAttach parachute

• Fill balloonFill balloon

• Attach balloonAttach balloon

CricketSat Flight SystemCricketSat Flight System• BalloonBalloon

• ParachuteParachute

• CricketSat sensorCricketSat sensor

Flight System MaterialsFlight System Materials

• CricketSat LP CricketSat LP temperature sensortemperature sensor

• 36” party balloon36” party balloon– May be purchased May be purchased

already filled with already filled with heliumhelium

– $10 filled, $3 not filled$10 filled, $3 not filled

• Model rocket Model rocket parachuteparachute– Estes 18” or 24”Estes 18” or 24”– $6.50$6.50

• 3 feet of cotton string3 feet of cotton string

• 8” plastic tie wraps 8” plastic tie wraps (qty 3)(qty 3)

• 1” wide double sided 1” wide double sided adhesive foam (qty adhesive foam (qty 2) 2) – Cut to 2” lengthCut to 2” length

• Helium if balloon is Helium if balloon is not filled at storenot filled at store

• MiscellaneousMiscellaneous– ScissorsScissors– Whiteout Whiteout – Rubber cementRubber cement

CricketSat Sensor CricketSat Sensor PreparationPreparation• Coat CricketSat sensor Coat CricketSat sensor

surfaces with rubber surfaces with rubber cementcement

• Attach batteryAttach battery– Use double layer of Use double layer of

foam stripsfoam strips

– Secure with single tie Secure with single tie wrapwrap

• Paint thermistor body Paint thermistor body and leads white using and leads white using whiteout whiteout

Attach Parachute to CricketSatAttach Parachute to CricketSat

• Locate the four Locate the four mounting holes on the mounting holes on the CricketSat sensorCricketSat sensor

• CricketSat will be CricketSat will be launched horizontally, launched horizontally, upside downupside down

• Route a tie wrap Route a tie wrap through the two holes through the two holes on each side, forming on each side, forming a loopa loop

• Pull loops together Pull loops together and attach parachute and attach parachute stringsstrings

Attach Balloon to ParachuteAttach Balloon to Parachute

• Place a small piece of Place a small piece of tissue wadding in tissue wadding in underside center of the underside center of the parachuteparachute

• Tie one end of the Tie one end of the string around this string around this wadding for the wadding for the parachute attachmentparachute attachment

• Tie the other end of the Tie the other end of the string to the balloonstring to the balloon

Ground System MaterialsGround System Materials

• CricketSat or ham radio UHF CricketSat or ham radio UHF receiverreceiver

• Stopwatch (interval delay)Stopwatch (interval delay)

• Watch (time)Watch (time)

• Paper and penPaper and pen

Final PreparationFinal Preparation

• Adjust CricketSat antennae to Adjust CricketSat antennae to produce a 90 degree “V”produce a 90 degree “V”

• Position thermistor to extend off Position thermistor to extend off the side of the circuit board, the side of the circuit board, placing it in the airflowplacing it in the airflow

• If using a ham radio, tune it If using a ham radio, tune it around 434 MHz to find the around 434 MHz to find the CricketSat signalCricketSat signal

CricketSat LaunchCricketSat Launch

• Take a few ground-based Take a few ground-based measurements before releasingmeasurements before releasing

• Release balloonRelease balloon

• Record at each tone:Record at each tone:– Time of dayTime of day– Interval delayInterval delay– Estimated temperature (from Estimated temperature (from

calibration chart)calibration chart)

Calibration ChartCalibration ChartCricketSat Temperature Calibration

-20

-15

-10

-5

0

5

10

15

20

25

30

35

15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39

Tone Burst Delay Interval

Te

mp

era

ture

(C

)