NORTHROP GRUMMAN MICROGRAVITY DRONE Group 23 Blue Team

NORTHROP GRUMMAN: MICROGRAVITY DRONE Group 23 Blue Team Adam Brockmeier, EE Jacob Knepper, Cp. E

INTRODUCTION We are constructing a quadcopter capable of achieving microgravity conditions Quadcopter is a four-motor unmanned aerial vehicle Microgravity is defined as a low gravitational force Rarely found on Earth’s surface Difficult to study, expensive to create

MOTIVATION Existing methods: Vomit Comet ($7, 000 -$40, 000 per flight, <25 lb)1 International Space Station ($10, 000/lb)2 Drop Towers (330 ft, <5 seconds, 3 x per day)3 Microgravity drone is a one-time expense Affordable option for students/researchers Unlimited number of experiments/no wait time 1 http: //www. gozerog. com/index. cfm? fuseaction=research_programs. welcome 2 https: //www. nasa. gov/centers/marshall/news/background/facts/astp. html 3 http: //www. esa. int/Our_Activities/Human_Spaceflight/Research/Drop_towers

GOALS/OBJECTIVES Design affordable drone capable of achieving microgravity flight autonomously Must be able to accommodate payload for research purposes Flight data will be recorded, logged, and relayed to ground station for observation by the user Drone must be able to recover from freefall and be set back up for repeated use

SPECIFICATIONS Freefall Time: 1 -9 seconds Altitude: 400 ft Payload Size: 12”x 7”x 4” (shoebox) Telemetry Data: Real-time and flight logs Microgravity Precision: 10 -2 to 10 -6 G Cost: $1, 500

BLOCK DIAGRAM

CRAFT ELECTRONICS

CRAFT POWER SYSTEM

GROUND STATION

SOFTWARE DESIGN APPROACH RC signal passthrough for user control PID loop to control downward acceleration Failsafe mechanisms to prevent crashes Automatic upload of experiment data to server Mobile application/webpage to retrieve experiment data

SELECTION OF FLIGHT CONTROLLER Brand Pixhawk Mini Pix. Falcon Micro F 4 Omnibus V 2 Price (USD) 229. 99 131. 12 24. 39 Mass (g) 15. 8 5. 7 Size (cm) 3. 8 x 4. 3 x 1. 2 3. 6 x 3. 6 Processor 32 bit STM 32 F 427: 168 MHz 256 KB RAM 2 MB Flash 32 bit STM 32 F 405 168 MHz 192+4 KB SRAM 1 MB Flash PWM outputs 8 8 6 Micro. SD Yes Yes Barometer MEAS MS 5611 Altitude Resolution: ± 10 cm BMP 280 Altitude Resolution: <10 cm

SELECTION OF MISSION COMPUTER Brand Raspberry Pi Zero ATMega 2560 ATMega 32 u 4 Price (USD) 5 6. 95 4. 80 Mass (g) 9 <5 <5 Size (cm) 6. 5 x 3. 1 x 0. 5 2. 7 x 1. 5 x 0. 4 5. 1 x 2. 3 x 0. 8 Operating Voltage (V) 5 5 3. 3 Memory 4 GB + SD card 256 K Flash 8 K SRAM 4 K EEPROM 32 K Flash 2. 5 K SRAM 1 K EEPROM Communication 1 -UART, 2 -SPI, 2 I 2 C, 16 PWM 4 -UART, 5 -SPI, 1 -I 2 C, 16 PWM 1 -UART, 2 -SPI, 1 -I 2 C, 12 PWM Processor 1 GHz, Single-core 16 MHz

GROUND STATION-MISSION COMPUTER COMMUNICATION 2. 4 GHz RC radio transmitter Used to control the craft before freefall Used to switch flight modes between freefall/manual Telemetry viewer application Monitor flight data in real time Mobile application/webpage Pull flight logs from a server after flight

MISSION COMPUTER-FLIGHT CONTROLLER COMMUNICATION PPM signal Sends movement commands to flight controller Roll, Pitch, Yaw, Throttle, Flight Mode One-wire signal to send all commands Flight controller handles stabilization algorithms Flight controller handles takeoff/landing

FLIGHT CONTROLLER-MISSION COMPUTER COMMUNICATION MAVLINK telemetry protocol Well-documented, well-supported protocol Mission computer receives sensor data from flight controller Mission computer uses sensor data to operate PID controller Telemetry data can also be sent to the flight logger and to the ground for real-time viewing

GPS SELECTION Brand u. Blox M 8 N GPS u. Blox SAM-M 8 Q GPS with SBAS receiver Price (USD) 14. 13 27. 99 Mass (g) 10 7. 5 Size (cm) 3. 7 x 1. 2 3. 0 x 1. 6 GNSS 3 Concurrent (GPS, Galileo, GLONASS, Bei. Dou) Supply (V) 2. 7 -3. 6

COMPASS SELECTION Brand Adafruit Precision NXP 9 -DOF Adafruit 9 Do. F+Temp IMU Digital Compass Breakout Board - FXOS 8700 + Breakout - LSM 9 DS 0 HMC 5883 L FXAS Price (USD) 14. 95 24. 95 8. 99 (Magnetometer) Mass (g) 2. 1 2. 3 0. 018 (compass) Size (cm) 2. 83 x 2. 05 x 0. 3 3. 3 x 2. 0 x 0. 2 0. 3 x 0. 09 Magnetometer Supply: 2 -3. 6 V ± 1200 μT magnetic sensor range 16 -bit data output Supply: 2. 4 -3. 6 V ± 2/± 4/± 8/± 12 gauss magnetic range 16 -bit data output Supply: 2. 5 -3. 6 V ± 8 gauss magnetic range 12 -bit data output Dynamically Canceled with Set/Reset Pulse Zero-gauss ± 10 μT level(Magnetom eter)

PAYLOAD VIDEO RECORDER/DATA LOGGER SELECTION Raspberry Pi Zero Inexpensive Capable of processing/ uploading data and video Brand Camera Video Module Webcam Mini Spy Camera with Trigger Price (USD) 13 12. 50 Mass (g) 3 2. 8 Size (cm) 0. 25 x 0. 2 x 0. 9 2. 85 x 1. 7 x 0. 42 Video resolution 2560 x 1920 (5 megapixel) 640 x 480 (. 307 megapixel) Supply Voltage (V) 5 3. 7 -5 Operating Current (m. A) 200 110

MOTOR SELECTION Brand KDE 3520 XF-400 Tiger U 5 T-Motor MN 4014 Navigator Price (USD) 112. 95 125. 90 99. 90 Mass (g) 245 156 150 Size (cm) 4. 2 x 4. 5 4. 25 x 3. 75 4. 47 x 3. 45 KV 400 400 Max Thrust (kg) ~3. 8 unspecified ~3. 0

ELECTRONIC SPEED CONTROLLER SELECTION Brand T-Motor 60 A Lumenier 50 A DYS 40 A Price (USD) 99. 99 24. 99 18. 99 Mass (g) 73. 5 7. 3 25. 2 Size (cm) 6. 65 x 3. 85 x 1. 87 3. 5 x 2. 1 x 0. 7 6 x 1. 7 x 0. 75 Features Heatsink, 60/80 A current BLHeli Firmware, active braking, reversible direction

BATTERY SELECTION Brand Turnigy Graphene Multistar Pulse (x 2 batteries) Price (USD) 179. 95 71. 74 188 (combined) Mass (g) 1610 1189 1768 (combined) Size (cm) 18. 3 x 7. 7 x 5. 7 15. 6 x 6. 5 x 5. 3 16 x 4. 9 x 5. 1 (each) Features Graphene technology, 10 C discharge, 35 C discharge, 12, 000 m. Ah 6, 000 m. Ah capacity 12, 000 m. Ah capacity, lightweight each, redundant doublebattery system

TELEMETRY RADIO SELECTION Brand 3 DR Telemetry Radio Set Micro HKPilot Telemetry Radio Set With Integrated PCB Antenna Hobbypower Radio Telemetry Ground Module Price (USD) 49. 99 39. 99 16. 98 Mass (g) 11. 5 1. 6 7. 2 Size (cm) 2. 55 x 5. 3 x 1. 1 1. 9 x 2. 5 x 0. 5 1. 7 x 5. 9 -117 -121 Receive Sensitivity -117 (d. Bm)

GROUND STATION INTERFACE SELECTION RC radio transmitter for craft control Telemetry viewer Full user control for safety Easily view telemetry in real time to track flight progress Mobile application/webpage for viewing experiment data View and download complete data and video logs after experiment

PCB SCHEMATIC

PCB SCHEMATIC - MCU

PCB SCHEMATIC - REGULATORS

PCB SCHEMATIC - PERIPHERALS

PCB LAYOUT

PCB LAYOUT - MCU

PCB LAYOUT - REGULATORS

PCB LAYOUT - PERIPHERALS

PCB PROTOTYPING

SCALE CRAFT TESTING

MOTOR/PROP TESTING Motors are able to produce 1. 5 kg thrust at 50% throttle. More extensive testing will be done with an improved test bench.

AUTOMATED RC COMMAND TESTING Confirmation of ability to directly control PPM values through Arduino code

CRAFT-GROUND STATION COMMUNICATION TESTING Data collected from flight controller is sent to Pi Pi will be capable of sending data over Wi-Fi to server Data is seen through web browser/application

CLASS DIAGRAM/SOFTWARE FLOWCHART Class diagram is in progress by the CS team

GROUND STATION UI

WORK DISTRIBUTION Adam Jacob MCU X Autonomous Flight Program X Power Distribution X PCB Design X ESC (PID configuration) X Telemetry X

BUDGET Item(s) Quantity Total Price (USD) F 4 Omnibus V 2 Pro 1 24. 39 Power Distribution Board 1 6. 34 u. Blox M 8 N GPS 1 14. 13 Brushless Motor Speed Controllers (50 A) 4 102. 95 Brushless Motors (designed for 6 KG takeoff weight) 4 459. 80 Propellers (subject to change, MAE must spec) 4 80. 00 Li. Po Battery (6 S, 6000 m. Ah) 2 188. 98 Hobbypower Telemetry Ground Module 1 16. 98 Raspberry Pi Zero 1 9. 05 Pi Zero Camera Video Module 1 13. 00 Adafruit Feather (With radio packet) 1 21. 73 Digital Compass HMC 5883 L 1 8. 99 Custom PCB + Components 1 33. 00 Price Total 972. 34

FINANCING Funded by Northrop Grumman $1500 final build cost $500 for research and development $2000 total budget

PROGRESS Research 85 Design 70 Prototype 50 Hardware Testing 50 Software Testing 30 57 Overall 0 10 20 30 40 50 60 70 80 90 100

ISSUES Division of groups at beginning of project Arduino-flight controller communication Communication method changed recently Telemetry radio setup Restrictive budget Tuning drone for stability

QUESTIONS ?