Project METEOR Instrumentation Platform P08101

Transcription

1 Project METEOR Instrumentation Platform P08101 Team Members (from left to right): Christopher J. Fisher (Project Manager), David J. Semione, Gabriela Eneriz Pereira Nunes, Brian A. Hanna, Sergey A. Yekimenkov May 16, 2008 Team #

2 METEOR Instrumentation Platform OVERVIEW: INSTRUMENTATION PLATFORM Mobile command station for project METEOR Facilitates communication with ground control and monitors rocket status Performs basic data collection: video, GPS, temperature, pressure and humidity Launches attached rocket and bursts balloon for platform descent MAJOR SUBSYSTEMS: Video Transmitter [Christopher J. Fisher] IP Data Link [David J. Semione] Control Board [Brian A. Hanna] Power System [Sergey A. Yekimenkov] On-Screen Text Overlay [Gabriela E. Pereira Nunes] May 16, 2008 Team #

3 METEOR Instrumentation Platform Date TEAM SPECIFICATIONS: Fully-functional ground tested unit Perform at least one test flight Meet all FCC and FAA requirements and RIT Policies and Procedures Budget of $5,000 Complete design, assembly and test documentation Description Cost 12/5/2007 Video Transmitter - PCB $ /6/2007 Video Transmitter - Parts $ /6/2007 Video Transmittier - Parts $ /6/2007 Video Transmitter - Inductor Kits $ /29/2008 Power - PCB $ /26/2008 Power - Parts $ /26/2008 Power - Parts $ /21/2008 OSD - PCB $ /21/2008 Temp. Sensors - PCB $ /21/2008 Controller - PCB $ /24/2008 Telemetry Transmitter - Parts $ /24/2008 Telemetry Transmitter - PCB $ /31/2008 Telemetry Transmitter - Parts $ /2/2008 OSD - Parts $ /3/2008 Team - MSP430 Flash Emulation $ /3/2008 Controller - Parts $ /3/2008 Controller - Parts $ /17/2008 Video Transmitter - PCB $ /17/2008 Video Transmitter - Inductor Kits $ /17/2008 Video Transmittier - Parts $ Total Cost May 16, 2008 Team # 8101 $3,

4 Video Transmitter MAJOR DESIGN SPECIFICATIONS: Carrier operating frequency of MHz, corresponding to cable channel 60 Output power greater than 1 W Output signal is NTSC format Operational from 0 ºC to 40 ºC Transmittable range of 500 km Verify transmitted signal to TV MEASURED RESULTS: Carrier frequency measured at MHz Pre-PA output power at least -6dBm, PA should yield about 37-38dB of gain Camera output is NTSC All components -20 ºC to 70 ºC or better Calculated range at 1 W, approximately 150 km. Need more than 11 W for 500 km range Verified to transmit video, albeit distorted May 16, 2008 Team #

5 Video Transmitter RF LO noticeably lower than expected for MAX2370. This is likely due to a matching issue. RF LO Filter specifications focused on band flatness and out-of-band attenuation. Additional tuning can be performed for better filter performance. IF Filter Output RF Filter May 16, 2008 Team #

6 IP Data Link Voltage translators: used to interface the IP data link board signals (5 V) with the main controller (3.3 V). MX614 modem: used to convert audio tones from the transceiver of TinkTrak SMT: integrated modem and TNC functionality for use in transmitting redundant GPS data. PI5A100 audio switch: alternates access to the transceiver between the TinyTrak and main controller. Access granted to TinyTrak for the majority of the time. May 16, 2008 Team #

7 DESIGN SPECIFICATIONS 1) Transmit data at MHz, United States APRS frequency. 2) Receive commands from ground control and route them to main controller. IP Data Link 3) Transmit position (GPS) and sensor data from the main controller. RESULTS 1) The level translation from 5 V to 3.3 V and vice versa necessary for modem/radio and controller interface has been successfully tested. 2) Received digital data has been successfully modulated into audio tones for transmission by the transceiver. 3) A problem with the line interface circuit to the modem is preventing transmit data from reaching the audio switch. An investigation is currently underway. May 16, 2008 Team #

8 DESIGN SPECIFICATIONS: Poll sensors for temperature, pressure, humidity and positional data Generate control signals to change cameras Transmit data to OSD for text overlay Generate control signals for radio transmission Transmit data to ground via radio subsystem MEASURED RESULTS: Temperature: 23 C, Pressure: 106kPa, Humidity: 38%, GPS: min N min W Altitude: 161.6m Control signals for video MUX and radio transmission were generated Can output serial data at 1200 BAUD Microcontroller May 16, 2008 Team #

9 Microcontroller SOFTWARE: The software for the microcontroller regularly polls data from the environmental and positional sensors and forms packets of this data to send to the 2m radio and OSD subsystems. It also generates control signals for the aforementioned subsystems. The software utilizes serial communication for data transmission and retrieval as well as analog to digital conversion for the analog sensors. The software can successfully poll the data from the sensors, generate control signals for the 2m radio and OSD and transmit data via the UART. The sensor data still needs to be placed in a form appropriate for radio transmission and code for transmitting data via SPI needs to be written. GPS Radio Uplink/Down link On-board Storage UAR T UA RT SPI I2C Sensors: Temperature Humidity A-D Con I2 C MSP430F16 9 Main Processor S PI On-Screen Display er vert GPI O Pressure and Humidity Sensors Extra Outputs: Cutdown Fire Rocket May 16, 2008 Team #

10 Microcontroller Power Up /Reset Initialize Ports APRS Packet Send Interrupt Service Routine Command Received Interrupt Service Routine Start Receiver Input Get GPS Data Get Temperature Data (4 External, 4 internal and 1 thermistor) Get Heading Yes TNC Count Done? No Get Humidity Send APRS Packet to TNC Yes Is it a valid command? No Get Pressure Switch to SPI Mode and Send Packet to SD Card Execute command false Altitude > ft true Reset Timer Send notification APRS Packet Period = 20 Return from Interrupt Clear command counters Return from interrupt false Roll Video Camera Video Camera Countdown done? true May 16, 2008 Team # 8101 Clear Watch Dog 10 Timer

11 Video Multiplexer and On-Screen Display Multiplex between eight analog (NTSC) video cameras Video signal will be relayed to ground control station to monitor the rocket before, during, and after launch; as well as monitor the status of the ascent balloon and descent parachute GPS and telemetry information is overlaid on video signal Acts as a redundant sensor information downlink Text overlay is receivable without the use of specialized radios or reception equipment Text overlay system must be portable Simple in-house software solution with minimal specialized hardware Video multiplexer and powering of the eight cameras work like desired. Problems with the MSP430 implementation are still being studied. May November 16, , 2007 Team #

12 Video Multiplexer and On-Screen Display Interrupt-driven operation ensures precise timing necessary for video generation Software-reprogrammable microprocessor can accommodate new updates as necessary This software should display the data received on the bottom of the screen. Cannot load code yet to the MSP430 microcontroller. A new revision of the board is under development to correct problems with JTAG connection. May November 16, , 2007 Team #

13 Power Board Main purpose of the Power Board is to supply power to all components of the platform for the duration of the flight. It must provide +3.3 V, +5 V, +12 V and -12 V. The required 18 V system supply is generated by five pairs of series connected 9 V Lithium-ion batteries. Switching regulators were used to convert the input voltage to the necessary voltage levels. May 16, 2008 Team #

14 Power Board LED lights were used to display the status of each regulator. Jumpers were used to disable voltages from going to the system at start up. Results showed that the board properly converts the input voltage to the desired output voltages required for the different parts of the platform. 9 V Li-ion BATTARIES SWITCHING VOLTAGE REGULATORS JUMPERS and LEDs 5.0 V, 3.3 V, ±12 V May 16, 2008 Team #