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COLLIDE-3 AVM. Walter Castellon CpE & EE Mohammad Amori CpE Josh Steele CpE Tri Tran CpE Sponsored by: Dr. Josh Colwell. Background. Planetesimal to Protoplanet to Planet is well understood Have gravitational forces Prior to this stage is still unclear
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COLLIDE-3 AVM Walter Castellon CpE & EE Mohammad AmoriCpE Josh Steele CpE Tri Tran CpE Sponsored by: Dr. Josh Colwell
Background • Planetesimal to Protoplanet to Planet is well understood • Have gravitational forces • Prior to this stage is still unclear • How do the particles stick together? • High velocity vs Low velocity impacts • Do they hold the key?
The Experiment • COLLIDE-3 will be attached to a sub-orbital rocket • Upon entering micro-gravity LED’s and a Camera will be turned on to record the experiment • Next a spherical quartz object will be dropped onto dust/simulant • The camera will record the results of the quartz object and dust/simulant in micro-gravity
The Problem • COLLIDE-3 scheduled to fly on private, experimental suborbital rocket • This rocket had an AVM module which would control all of the functions of COLLIDE-3 • The rocket had problems, and was no longer available to us • Dr. Colwell was left with an experiment, but no way to run it • Needed a new AVM if he wished to utilize his experiment on a different rocket.
AVM (Avionics Module) • Brain of experiment • Manages hardware/power • Runs COLLIDE-3 • Record results • Store results
Requirements • Connected to 28VDC source and 120VAC sources • Low weight • High vibration resistance • Fully automated • Capable of recording greater than 80fps at 640x480 at times ranging from 30s-2m • User friendly • External access to flight variables • Experiment must always update with these new variables • Cost efficient
Hardware Block Diagram SSD P820 DM CAMERA Microcontroller H48C MUSCLE WIRE LEDs MICROSTEP DRIVER
AVM Components • EPIA P820-12 embedded board • Microcontroller • Camera • LEDs • Solid State Drive • Accelerometer • Display Module • Stepper Motor • Micro-step driver • Muscle wire • Wireless Comm
Standard Components • LEDs: 2 LED arrays each array has 48 LEDs • Micro-step driver: requires 12v, 5v, PWM • Muscle wire: 1 amp of current at 5V
Camera • AVM will be able to support both industrial and consumer cameras • SVSI “Stream View-LR” and GoPro “HD Hero” • GoPro is a consumer camera used during initial experiments to reduce financial loss in case of rocket failure • SVSI is an industrial camera that will be used more often in the long run
Display Module • Can use either serial or USB interface • User friendly software • Will allow user to view current experimental variables
Display Menu • Displays all experimental variables • Delay after microgravity • Delay to record • Recording duration • Updates every 1 second
External Communication • Rocketfish micro-USB bluetooth adapter • Data transfer of 3 Mb/s • Range of 20 feet • No interference • Minimal weight and footprint
Wireless Access (via BT) • Supported by: • Windows XP, Vista, 7 • MAC OS 10.4 and later • Default shared folder is AtMega code • Variables will be top 3 lines for ease of access • Copy file locally make changes copy back to shared folder
Solid State Drive • Using SATA II connection write speed is 95 MB/s • Shock Resistance is 1,500 G • Vibration Resistance 2.17G – 3.13G (Operating – Non-Operating)
Accelerometer • Parallax H48C • 3-axis readings • Unfortunately, support is for PBASIC language • Need conversion for ATMega • Reads in voltage outputs from each axis and converts into a G-rating using the following forumula: • G = ((axis – vRef) / 4095) x (3.3 / 0.3663) • Our code must do this conversion
Accelerometer – False Positives • Pins can sometimes falsely detect G-levels • Costly mistake that needs to be protected against • Will have counter loop that continuously checks flag every .4ms • If pin consistently reads zero gravity for set amount of time, it is not a false positive, and experiment can proceed
EPIA P80-12 • Hosts the experimental code and the variables that can be changed externally. • Uploads procedure code to the microcontroller • Activates recording for the camera • Handles high speed image transfers from the camera
EPIA P80-12 • Cost is $310 • Windows board • Compatible to all cameras • Flexible to experimental changes • User friendly • Excellent hardware and software support • Smaller form factor
Microcontroller • Stores experimental variables and procedure • Reads in microgravity mode from accelerometer • Utilizes relays to activate COLLIDE-3 components • Communicates with EPIA P820-12 to power on camera
ATMega328 • 6 dedicated PWM lines • Small footprint • Meets basic requirements • I/O pins • Memory (RAM, EEPROM) • Serial/USB pins • Larger support base • C language (all members familiar) • Familiarity
FT232R Breakout Board • Allows communication between the Arduino program on the P820-12 and the ATMega328 • Utilizes the ATMega’sTx and Rx lines
Power Conversion • Rocket will only provide standard AC sources and a 28V DC power supply • Our components take 5,6, and 12 volts • 12V: Microstep VCC, LEDs • 6V: Microstep input, muscle wire • 5V: ATMega328 • Will utilize DC-DC converters and regulators to convert the 28V to usable levels
EC7A-24S12 • 12V requirements will be handled by CINCON EC7A-24S12 • Input voltage range of 18-36VDC • Output voltage regulated at 12V with output current of 835mA
PT78ST106H • 6V requirements will be handled by POWER TRENDS PT78ST106H • Takes input voltages from 9-38V • Outputs a constant 6V voltage at a current of 1 amp • Will utilize two of them, since we will use more than 1 amp of current at 6V
LM7805 • Finally, 5V requirements will be handled by a standard LM7805 5V regulator • Instead of regulating the 28V input source, this will simply be taking in a 9V battery
IMB03C • Since the microcontroller cannot provide enough volts/amps to power COLLIDE-3’s components, it will instead activate a relay, which will have a load of the regulated voltages from the sources previously mentioned • We will implement the AXICOM IMB03C mechanical relay • Handles up to 2A of current • Functions up to 300g of shock, survives up to 500g of shock • 100uV control voltage will switch relay, which can have a load up to 220V
Software Flow Chart Start
Project Issues(Technical) • Communication protocol between EPIA P820-12 and ATmega328 (FT232R) • Camera compatibility • Changing variables externally
Project Issues(Nontechnical) • Mono • Theft • Crashes