WVU Returns to RockSat 2010: A Research and Education Project

WVU Returns to RockSat 2010: A Research and Education ProjectWest Virginia University Rocketeers Student team: N. Barnett, R. Baylor, L. Bowman, M. Gramlich, C. Griffith, S. Majstorovic, D. Parks, B. Pitzer, K. Tewey, E. WolfeFaculty advisors: Y. Gu, D.J. Pisano, D. Vassiliadis

June 2010

11The mission of WVU RockSat is to design, build, and test three atmospheric and plasma physics experiments: a temperature measurement, a vector magnetic field probe, and a radio-sounding plasma-density measurement. We expect to obtain height profiles for the first two experiments and get a proof of concept for a novel plasma measurement.Mission StatementMission Overview: Radio BoardMeasured variable: plasma density. Processes: solar UV produces ionosphere >85 km.Objectives:Emit radio pulse which is reflected where index of refraction=0Measure density profile; identify E layer peakFor high-activity conditions: high-density patches descend to E-layer altitudes (spread-F effect)

Mission Overview: Main BoardMeasured variable: temperature. Processes: atmosphere heating/cooling mechanisms. Objective: identify layers based on temperature profile

Measured variable: terrestrial magnetic field. Processes: field controls charged-particle motion. Objectives: Measure vector B, dependence on latitude, geocentric distance.For high S/N: detect low-frequency waves

4Mission ResearchMagnetic field: Strongly involved in plasma structure and dynamics. Experiment measures power-law decrease of field magnitude with geocentric distance. differences in Earth's magnetic field can be caused by the interaction between charged particles from the Sun and the magnetosphere of a planet

6WVU Functional Block DiagramMain BoardPower flow

Comm/Con

Data flowLegendPower/Reg

Comp/Store

SensorsPower SupplyThermistoruMag X/Y/ZG uControllerFlashMemoryRBFZ AccelGyro X/YADCInertialSensorRegDIGITALGeigerCounterMag X/Y/ZP/Q/RAx/Ay/AzTemperatureBatteryuProcessor: Netburner MOD5213

Programming Language: C++

Programming Requirements: Periodic Interrupt Timers (PIT)8 Analog to Digital PinsSerial Peripheral Interface (SPI)5 Digital GPIO PinsWrite 19 sensor channels to binary text fileWrite to external storage using a serial portadditional serial port for uploading software

Main Board PCB Vertical Breakout BoardGeiger Counter

Included a Geiger counter in payload to help verify Plasma Density experiment WVU in RockSat 2010: Functional Block Diagram1010Power SupplySwept-fPulse TxRadio BoardFixed-fPulse TxPre-amp &Power filterSuperhetLOAmplifierIFG RegsANTRF inuControllerADCFlashMemoryANTANTRF out10Solenoid valveTransmitter SchematicLatest testingTransmitter works on PCB when high-resonance frequency (>2 MHz) inductors are used.

If in addition, inductances are high, then we can use low capacitances.

Receiver Schematic14Programmable Circuit Elements Programmable Capacitor used to control Transmitting and receiving frequencies

The Mod5213 PIT is used to control the digital capacitor (Max 1474)

We control simultaneously multiple capacitors: useful in extending range or resolution of effective capacitance

Final Payload

Concluding RemarksConstructing our RockSat payload was a great hands on learning experience for experimental design and build.WVU looks forward to participating in the next RockSat.

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Capacitance (pF)Number of PulsesCapacitance (pF)

Sheet1Number of PulsesCapacitance (pF)02.112.522.933.343.75464.474.885.195.4105.8116.2126.5136.8147.2157.5167.8178.1188.5198.8209.1219.4229.72310.12410.42510.726112711.32811.62911.93012.23112.5

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Capacitance (pF)Number of PulsesCapacitance (pF)