BalloonSat Telemetry Module Christopher Arthur Jonathan Berry Jeb Orr Project Final Design Review April 25, 2006 CPE , Spring 2006 Agenda Project Summary Accomplishments Performance Hardware and Firmware Testing Flight Results Costs and Labor Conclusions and Recommendations Project Summary BalloonSat Telemetry Module Hardware ModuleHardware Module Sample analog or digital data Transmit data back to the ground station in real time Ground Station SoftwareGround Station Software Decode recorded data received by the ground station, output to CSV Produced two modules meeting the needs of the BalloonSat team Samples up to eight channels at a continuous rate of about 1.5 HzSamples up to eight channels at a continuous rate of about 1.5 Hz Module transmits AX.25 frames containing a compact ASCII representation of the data: Example: NV4B>TLMTRY:7E836076Module transmits AX.25 frames containing a compact ASCII representation of the data: Example: NV4B>TLMTRY:7E Device is packaged in a robust, reusable aluminum enclosureDevice is packaged in a robust, reusable aluminum enclosure Accomplishments Accomplishments (continued) Power consumption and weight requirements met with plenty of room to sparePower consumption and weight requirements met with plenty of room to spare Produced ground station software to automate the conversion of the ASCII hex data to voltage values; this software also produces CSV files for easy data analysisProduced ground station software to automate the conversion of the ASCII hex data to voltage values; this software also produces CSV files for easy data analysis Performance All critical requirements met Some capabilities not implemented The flight date was a week sooner than expected; working module was ready on April 8The flight date was a week sooner than expected; working module was ready on April 8 Device limitationsDevice limitations Very little RAM Only one timer Codebase limitationsCodebase limitations AFSK routine not interrupt-driven Hardware Two complete modules constructed Only one small modification to schematic and PCB since preliminary design Microcontroller device programmer breadboarded COTS radio (Alinco DJ-C7T) required no modification Firmware Based on OpenTracker firmware as planned Binary-to-ASCII hex conversion implemented in firmware Compiler directive selects the number of channels to transmit Status LED configured to light during transmission AFSK accomplished with PWM of a timer pin in conjunction with a sinewave LUT Transmission takes place at a constant rate with PTT de-asserted between packets Flight duration timer shuts down module after specified number of packets Testing Functionality Testing Basic prototype built for low- level AFSK testingBasic prototype built for low- level AFSK testing Results were not observable on scope but audible tones were obviously correctResults were not observable on scope but audible tones were obviously correct TNC Integration Testing Code was written to transmit the same packet continuouslyCode was written to transmit the same packet continuously AFSK fed directly to TNCs input; TNC decoded and displayed the data properlyAFSK fed directly to TNCs input; TNC decoded and displayed the data properly Testing (continued) Integration Testing with BalloonSat Package Ground test conducted April 8, 2006 with a module on each of two different packagesGround test conducted April 8, 2006 with a module on each of two different packages Module was connected to payload power supply and BalloonSat teams sensorsModule was connected to payload power supply and BalloonSat teams sensors Test was successfulTest was successful Encoding Reliability/Error Detection Testing None implemented; relied on AX.25s inherent frame-check sequenceNone implemented; relied on AX.25s inherent frame-check sequence Testing (continued) AX.25 and AFSK Encoding Testing Achieved during integration testing with TNCAchieved during integration testing with TNC Proper ADC data representation tested by stepping through voltage levels with a precision power supplyProper ADC data representation tested by stepping through voltage levels with a precision power supply On-air Data Transmission Testing In the lab during ADC calibrationIn the lab during ADC calibration During the ground testDuring the ground test During actual flightDuring actual flight Testing (continued) Ground Station Software Testing Ground station software was tested with sample input file; sample input was successfully decodedGround station software was tested with sample input file; sample input was successfully decoded Test results reinforced with successful decoding of the ground test dataTest results reinforced with successful decoding of the ground test data Flight Results ORION-I 10:50 a.m. April 9, 2006, NSSTC Flight Results Anomalous data noticed at 12:12 p.m. after 1 minute data loss; all data lost around 12:25 p.m. Chase team met in Fyffe, AL to coordinate search (no position data available) Around 1:30 p.m., first signals heard west of Fyffe Direction finding led to house in Macedonia community of Jackson County where payload was recovered, 40 miles from the launch site Large amount of data received from our module, which never stopped transmitting Flight Results Raw Data Sample NV4B>TLMTRY [04/09/06 12:11:11]:777D6B83 NV4B>TLMTRY [04/09/06 12:11:11]:787D6B81 NV4B>TLMTRY [04/09/06 12:11:12]:787D6B81 NV4B>TLMTRY [04/09/06 12:11:13]:787C6B81 NV4B>TLMTRY [04/09/06 12:11:14]:777E6B83 NV4B>TLMTRY [04/09/06 12:11:15]:777E6B81 NV4B>TLMTRY [04/09/06 12:11:17]:777E6B80 NV4B>TLMTRY [04/09/06 12:11:18]:787C6B81 NV4B>TLMTRY [04/09/06 12:12:12]:73626B69 NV4B>TLMTRY [04/09/06 12:12:15]:695D6B45 NV4B>TLMTRY [04/09/06 12:12:15]:3A826C00 NV4B>TLMTRY [04/09/06 12:12:17]:747B6C49 NV4B>TLMTRY [04/09/06 12:12:18]:5E4F6B53 Flight Results CSV Data Flight Results -- Data Flight Results ORION-II 10:20 a.m. April 15, 2006, NSSTC Flight Results Flight was less successfulhad difficulty decoding the packets sent Noise may have been induced in module or in ground station Some data was recovered APRS Position data was lost again radiolocation search proved unsuccessful Last signal heard south-southwest of Section, Alabama as the balloon fell from the sky around 11:30 a.m. Flight Results Cost and Labor Cost per unit was $249 ($260 budgeted) $180 for radio$180 for radio $20 for PCB$20 for PCB $49 for parts, enclosures, microcontrollers, etc.$49 for parts, enclosures, microcontrollers, etc. Project took over 200 man-hours to complete Conclusions Project was a success Future work is recommended to add functionality Implementation of serial port and configuration utilityImplementation of serial port and configuration utility Implementation of interrupt-driven AFSK routine to allow higher ADC sampling rates; this may require a significant amount of work and could be suitable for a future design projectImplementation of interrupt-driven AFSK routine to allow higher ADC sampling rates; this may require a significant amount of work and could be suitable for a future design project Questions?