SOARS-CDR

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					                                SOARS
                   Self Organizing Aerial Reconnaissance System




                                                             Arseny Dolgov
                                                               Nick Driver
                                                            Galina Dvorkina
                                                             Kevin Eberhart
                                                             Matt Edwards
  Critical Design Review                                    Johnny Jannetto
ASEN 4018 Senior Projects                                      Eric Kohut
          11/15/06                                            John Shelton
 Professor Dale Lawrence
Professor James Maslanik                                                      1
          Presentation Outline
•   Overview and Objectives
•   System Architecture
•   Critical Test Results
•   Design Elements
    • Electrical Design
    • Software Design
• Integration and Verification
• Project Plan & Management
• Appendix



                                 2
                                                 Project Overview
                      •     Objective: Design, build and test an autonomous aerial system (UAS)
                            capable of imaging multiple targets within a 1km circle as quickly as
                            possible with 99% probability of object detection (according to Johnson
                            criteria).

                      •     AFRL COUNTER Project
                              •    Optimal imaging altitude <100m for a small aerial vehicle
                              •    Minimize risk to larger master vehicle




                                                    Master




                 GPS Coordinates,
                 Heading                                                 Slave                     Truck


                                                                                     hmax = 45 m
                                                                                                   Target
             Ground Station



1. AFRL COUNTER Project. Used with permission.                                                      (X,Y,Z)   3
Test Scenario




                4
          Requirements Overview
• Image at least 3 targets, satisfy Johnson Criteria
   •   Time: <8 minutes
   •   Flying distance: >4 km
• Slave UAV >1km radius of operation in relation to stationary
  (assumed) Master vehicle
• Targets given by GPS location and heading from ground
  station
• Slave UAV
   • Max weight: 1.5kg
   • Maximum width for below-wing mounting:
      120 cm
• New critical requirement: Image lag < 2 seconds from slave
  to ground-station
   •   Motivation: Operator must react quickly if a threat is detected
   •   Camera image retrieval takes at least 1 second




                                                                         5
                                                                      Deliverables
                         Fully loaded take-off and deployment of
                        two slaves. Advanced flock management.        Future COUNTER Mission




                           Demonstrate ground-deployment of
                                        slave.
Increasing Complexity




                            Demonstrate “theoretical” slave
                           deployment capability w/ designed
                                    mechanism.
                                                                      Target System     • Selection of slave vehicle
                                                                                        • GS to Master to Slave RF link
                                                                                              • Image reception
                         As below, but coordinates and pictures
                            relayed through master vehicle.                                   • Target specification
                                                                                              • Demonstrate <2 sec image
                                                                                                delay
                        Slave flies to and loiters above any target
                        specified by GS and sends back pictures.
                                                                                        • Slave telemetry (GPS position,
                                                                                         altitude, heading, speed)
                                                                                        • 3 Images taken with correct
                          Slave loiters above preprogrammed
                               target, acquiring images.
                                                                                         position, attitude (Johnson criteria)
                                                                                        • Autonomous navigation
                                                                                        • Deployment feasibility

                                                                                                                                 6
                                     Requirements Summary
                    Slave Vehicle                               Master Vehicle                                          Ground Station


·   Telemetry/Images Sent over >1km to Master
                                                                                                         ·   Slave telemetry update rate: 1Hz
·   Delay to receiving image: <2sec                 ·   Relay 640x480 images in <2 sec                   ·   Identify image w/ location and timestamp
·   >3 Targets imaged, satisfying Johnson Crit.     ·   RF Link endurance >20min                         ·   Send target (GPS, heading) commands to
·   < 10% Image Blur                                ·   >2km range to Ground Station                         slave via master
·   Travel at least 4km in 8 minutes                ·   Manually Piloted RC                              ·   Range to Master: >2km
·   Autonomous navigation to GPS coord, heading     ·   Must be able to carry Micropilot module          ·   Receive 640x480 images in <2 sec
·   Deployable from SIG Master vehicle



                                                           Communications                                        Graphical User
          Control
                                                                                                                   Interface
                               Pitch within 30°                                 Data relay, >250kbps                                      GPS XY Input
                                Rate < 12°/s                                       < 2 sec delay                                          Heading Input

                               Roll within 30°                                  Must fit inside 5x10x5                                Display 640x480 image
                               Rate < 115 °/s                                           cm box
                             Heading within 30°                                                                                       Display slave telemetry:
                               Rate < 12°/s                                         Range: >2km                                          position, velocity

                            Position accurate to                                                                Communications
                                                               Power
                                    10m
                                                                                  > 20 min operating                                   Receive Data at 1Hz
      Communications
                                                                                   time for avionics/
                                 Bandwidth                                        comm subsystem
                                 >250kbps                                                                                                  Range >2km

                             <2 seconds image
                                   delay                                                                                               Bandwidth >250kbps


           Power                                                                                                Control Software
                                                                                                                                     GS-Master Handshaking
                                Range > 4km

                              Speed > 30km/h                                                                                          Ensure slave receives
                                                                                                                                           command

           Imaging

                            Resolution >300 lines


                              30° < FOV <60°


                             Working Distance
                                  <90m                                                                                                                           7
              System Architecture: Slave
  •Slave requires custom interface and power board to house camera and
  send data to CU Autopilot.
  •Custom autopilot and controls software will be developed to meet target
  imaging requirements.


                                                                     SLAVE VEHICLE
                                       1000mAh                                 Daughter Board
                                      LiPo Battery                                        CMOS JPEG
Design and Fabricate PCB                                                                    Camera
(Printed Circuit Board)
                                                                       3.3 V
                                                                      Regulator                Level Shift



                                                                              115kbps Asynch

        Power Subsystem                              CU Autopilot
                                       Rate Gyro
                                                                PIC Microcontroller
       Processing Element                                         Control Software
                                       Altimeter                                                             Servos

        Communications
                                         GPS

                                                                                                              ESC
                                       Receive Buf   Send Buf

                                         Short-Range ZigBee
                                      Transceiver, 250kbps OTR
                                                                                                             Motor



                 TO MASTER @ 2.4Ghz
                                                                                                                      8
                          System Architecture: Master
            •Master houses two COTS radios
                       •1 long-range point-to-point (for communication with ground-station)
                       •1 short-range multipoint (for communicating with multiple networked slaves)
            •CU autopilot provides data for verification, maintains master UAV loiter
            •Custom microcontroller software handles command dispatch and data/telemetry

                                                                            MASTER VEHICLE
                                                                                                                                Motor
                                                                             CU Autopilot
   Power Subsystem
                                                                          PIC Microcontroller
                                                                                                                                 ESC
                                                                            Stock Software
  Processing Element
                                                                                                                                Servos
   Communications                     1000mAh
                                     LiPo Battery
                                                                Microcontroller – PIC18F8722

                                                                               Control
                                                                              Software
                                        5.0 V                                                                         3.3V
                                      Regulator                                                                     Regulator
                                                                UART0                         UART0
Design and                                                    Receive Buf                   Receive Buf
Fabricate PCB                                                                                                  250kbps Asynch
                                                               Send Buf                      Send Buf

                                                                                                                  Level Shift
                                       800kbps Asynch



                                    Send Buf    Receive Buf                                                Receive Buf     Send Buf

                                     Long Range Radio                                                        Short-Range ZigBee
                                    Modem, 800kbps OTR                                                    Transceiver, 250kbps OTR



      TO GROUND STATION @ 2.4 Ghz                                                                                                        TO SLAVES @ 2.4Ghz
                                                                                                                                                              9
System Architecture: Ground Station
 •Ground station houses 1 long-range radio for sending commands to master
 •Laptop uses software to interface directly to radio – no need for MCU.
 •MATLAB interfaces with/controls Aerocomm development board via serial link
      •MATLAB GUI allows user to enter target location, issue commands
      •Image and telemetry display


                                       USB Power


                Aerocomm Development Board              250kbps Serial to USB
                                                             Converter
                           800kbps Asynch



                      Send Buf     Receive Buf

                      Long Range Radio
                     Modem, 800kbps OTR



     TO MASTER @ 2.4Ghz


                                                   Target GPS: XYZ
                                                   Heading: θ°
      Power Subsystem

      Processing Element

       Communications




                                                                                10
                   Slave Component Layout
    Rate Gyro                        GPS Antenna

RC Receiver                                  ZigBee Radio




Ducted Fan

                                                               2.4GHz RF Antenna


                                                          ESC
Camera Mount
Under Wing                                           LiPo Battery Pack


                                          Elevon Control Surfaces
   Custom Canopy


                                         Winglet Stabilizers

                                                                             11
                           Complete System Assembly
        Comm Board & Battery
        Pack




SIG Rascal 110 ARF




  Slave Vehicle




                                      Mounting Pylon   12
     Expected Performance
•   Autopilot
•   Imaging
•   Communications
•   Propulsion & Power




                            13
                        Autopilot Performance
•   Vector field guides slave UAV to arbitrary target and heading
•   Total distance traveled for three targets: 7 km
•   Minimum speed for mission length <8 min: 33 mph




                                                                    14
                                                                         Trajectory Control
                                                           SOARS PATH CONTROL SYSTEM BLOCK DIAGRAM
                                                                                                                                                                                  Assume
                                                                                                                                                    Integrator                Coordinated Turn
    Commanded
                        com
                                         Roll Angle
                                                               Vs s 
                                                                                    Commanded
                                                                                                                                                                                   g  tan( )
     Roll Angle                            Error e                                 Servo Voltage              Plant                                                             
                                                                                                                                                                                 
                                                               e s 
                                 +
                                     -
                                                                                         Vs                  (Vehicle)                Actual Roll      1         Roll angle
                                                                                                                                                                                           V
                                                                                                                                         Rate
                                                                                                                                                       s
        +
    +


                                                                                                                                                                      Heading Rate 
                                         ˆ
                                         
                                                                          ˆ
                                                                          
                                                      1                                      Rate Gyro
com_ s                                            s                                                                                     Physical
 e s
                                                                                                                                             Model
                                                                                                                                                                                       1
                                                                                                                                                                     Integrator
                                                                                                                                                                                       s
            Heading
             Angle               Software                                                      Sensor
                                                                                                                              X
            Error eΨ                                                                                                                      HEADING ANGLE
                                                                                                                                  Vehicle
                                                                                                                                            DEFINITION
                                                                                                                                      
                                                                                                                                                                                   
                                                                                                                                      x                                  Actual Heading
                                    dx 
                                      ˆ                                                ˆ ˆ
                                                                                       X ,Y                                                    V                             Angle
        -                    tan  
                            ˆ       dy 
                                         1
                                                                   s                                GPS                                   
                                    ˆ
    +
                                                                                                                                                
                                                                                                                                                y
                                                                                                                                                                 Y

                                              V 
                           com_  tan1 
                                
                                       
                                          g 
                                                                            d
                                                                              
                                                               Desired Heading Rate                                  X ,Y
                                                                                                                                  1             
                                                                                                                                               x, y         x  V cos 
                                                                                                                                                            
                                                                                              Vector Field
                   d
                                 d  tan 1 
                                                   dxd    
                                                           
                                                                          
                                                                         xd , y d                                 Position        s         Velocity        y  V sin  
                                                                                                                                                            
                Desired                                                                                                                 Components
             Heading Angle                         dy d          Desired Velocity
                                                                    Components                                               Integrator

                                                                                                                                                                                                    15
                 Imaging Performance
                                                  Quick Imaging Geometry Facts

           Tangential Velocity                    •Max Imaging Range: 80 m
           Required: <60 m/s                               (actual: 65 m)
           Actual: 15 m/s                         •Camera can see 19,000 m2
                                                  •Airplane is in imaging window
                                                           for 2.7 s

        Cruise velocity: 17 m/s
Pitch Rate
Required: <0.4 rad/s              Depression
Actual: 0.2 rad/s                 Angle: 45 deg


                        Radial Velocity                Imaging Altitude: 45 m
                        Required: <80 m/s
                        Actual: 8 m/s



       Ground distance to target: 45 m

                                                                                   16
                           Communications Performance
     •      Communications subsystem must ensure <2 seconds image propagation
            delay
              •      Camera outputs 16kbyte JPEG images
              •      Slowest link in system must be >115kbps
     •      Current system limited by image retrieval speed from camera
              •      115kbps bottleneck in camera interface
              •      No other camera available with built-in JPEG compression
              •      Most cameras output RAW format in 8-bit parallel, image size too big (>400kbytes)
     •      Communications system has large margin (250kbps minimum data rate) to
            leave room for protocol overhead, errors and dropped packets

    Ground Station                                        Master Vehicle                         Slave Vehicle
                               800 kbps                                               250 kbps
                                                                                                    Radio 1
         Radio 4
                                                Radio 3                     Radio 2

      800 kbps                                                                                    250 kbps

                                               800 kbps                    250 kbps
          MCU                                                                                        MCU
                                                              MCU

      250 kbps                                                                                    115 kbps

Graphical User Interface                                                                         Camera Module




                                          Actual Path Delay: 1.4 s
                                                                                                                 17
Critical Pre-CDR Test Results




                                18
                      Critical Testing: Camera Jitter
     •     Image blur/distortion due to engine jitter and vibrations is unpredictable
           and must be tested
     •     High-frequency (kHz range) vibrations cause CCD to move while rows of
           pixels are read – resulting image gets shifted between row reads
     •     Engine must be
                                                 Current Read Row       Blur – Shutter too slow:
           stopped during imaging

         Engine OFF
                             CCD
                             Scan
                             Direction
                                                                                  Rolling Shutter Distortion:



                                         Camera Movement Direction

Engine ON, 80% Throttle      Engine ON, Camera Rotated 90°
                                                                                  Fast Global Shutter:




                                                             [1] Electronic Shuttering for High-Speed CMOS. - Dalsa Corp. 19
 Critical Testing: Camera Resolution
• JPEG compression might cause loss of effective camera
  resolution: must be verified experimentally
• Resolution test pattern used to verify actual resolution
• Test indicates no noticeable loss in camera resolution
• Camera meets design-to specification of >300 lines




                                      Lines become indistinguishable
                                      at approximately 400 lines of
                                      resolution marker

                                                                       20
               Critical Testing: Power System
•   Wingless ducted fan tested at 56mph (manufacturer’s optimal speed) in
    the wind tunnel to simulated actual load conditions
• Measured battery discharge voltage and current
     •   ElectriFly: 3 Li-Polymer Cells
     •   11.1 Volts
     •   910 mAhr
     •   Ran for 5.5 minutes



                                                        Li-Polymer Battery Discharge

                                    13


                                    12


                                    11
                          Voltage




                                    10


                                    9


                                    8
                                                           0

                                                           0

                                                           0

                                                           0

                                                           0

                                                           0

                                                           0

                                                           0

                                                           0

                                                           0

                                                           0

                                                           0
                                     0
                                         20

                                              40

                                                   60

                                                         80
                                                        10

                                                        12

                                                        14

                                                        16

                                                        18

                                                        20

                                                        22

                                                        24

                                                        26

                                                        28

                                                        30

                                                        32
                                                                      Time (s)         21
Electrical Design




                    22
 Electrical Design: Communications



• Master to Ground: Aerocomm AC1524 Modem
• Master to Slave: X-Bee PRO ZigBee Radio
• Multiple selectable channels on each radio to prevent
  interference


Required: 250 kbps
Actual: 800 kbps                            Required: 250 kbps
                                            Actual: 250 kbps




          Required: 2 km            Required: 1 km
          Actual: 3.2 km            Actual: 1.6 km          23
          Electrical Design: Power
•   Slave UAV power requirements driven by propulsion system
    (avionics consume <2% compared to motor)
•   Master UAV requirements driven by high-power RF transceivers




                                                                   24
                      Electrical Design: Power
• Slave avionics must operate for >8 minutes
   • Battery: 3-Cell 1800mAh LiPo
• Master avionics must operate for >30 minutes
   • Battery: 3-Cell 1000mAh LiPo
• Master UAV power supply design-to:
   • Input Voltage : 7.5V-11.1V due to LiPo discharge variation
   • Outputs:
       • 1A @ 5.0V for Long-Range transmitter
       • 500mA @ 3.3V for Short-Range Zig-Bee radio

                                     Li-Polymer Battery Discharge

                 13


                 12


                 11
       Voltage




                 10


                 9


                 8
                                        0

                                        0

                                        0

                                        0

                                        0

                                        0

                                        0

                                        0

                                        0

                                        0

                                        0

                                        0
                  0
                      20

                           40

                                60

                                      80
                                     10

                                     12

                                     14

                                     16

                                     18

                                     20

                                     22

                                     24

                                     26

                                     28

                                     30

                                     32



                                                   Time (s)
                                                                    25
         Master UAV Comm Board Layout
•   Minimize trace length for high-frequency/data rate signals
•   Power supply decoupling close to MCU pins to minimize noise from RF
•   Bottom-layer ground plane to reduce noise
                                                 Long Range Radio Modem




                                             PIC Microcontroller

                                           Power Supplies




                                           ZigBee short-range Radio       26
            Electrical Design: Slave UAV Daughter Board
   • Slave “daughter board” connects to main autopilot board
         • Provides camera connection and power (from main LiPo battery)
         • Provides SPI-to-Asynchronous bridge from MCU to Camera
         • Translates voltage signals between 5.0V and 3.3V


                                                          Camera Header




                                                         Level Shifter
   Power Supply




  SPI Header


                                                       Crystal



SPI Bridge Chip


                                                                          27
Software Design




                  28
              Software Design
• Design-to:
  • Slave
     • Control algorithm must ensure proper entry into imaging
       cone
     • Perform imaging within allowable window of opportunity
     • 250kbps image uplink rate
     • Update X,Y,Z, heading, velocity at 1Hz
  • Master:
     • 250kbps data throughput
     • Manage at least 2 slaves
     • < 2 seconds image data lag
  • Ground Station
     • Allow Lat/Long/Heading target designation
     • Image display
     • Telemetry display & update at 1Hz



                                                                 29
                        Power-On         Software: Slave
                     Initialize System
                                            • Software performs major function of:
                    Main Loop
                          Read                 •   Hardware Configuration
                         Sensors               •   Control Implementation
                       Read GPS                •   Imaging Control/Transmission
                                               •   Telemetry Transmission
                     Process Ground
                       Commands             • Servo and Peripheral communications
Interrupt Service
                        Read RC               handled via interrupt service routine
Routine
                        Receiver
  UART Receive/                             • Major additions are ability to receive
    Transmit         Execute Control
                       Algorithms
                                              ground commands in flight and
   RC Receiver                                imaging system
    Handler            Mix Servos
                      (for Elevons)
    Send PWM
    commands            Command
     for servos          Servos

                     Imaging Control
     Denotes Key
      Additons            Send
                        Telemetry

                         Safety
                         Routine
                                                                                       30
                                                 Slave: Imaging Software
                                                    Imaging Control
                                                                                                    •     Compressed image sent as
                                                                                                          packets (64-512 bytes)
                                     No
                                                    Image Transfer
                                                     In Progress?
                                                                                Yes                 •     Image will be taken with 6 byte
                                                                                                          configuration information
                                                                                                    •     Location information (Lat,
                               Within Imaging                           Last Image Data
                Yes              Window?                               Packet Complete?                   Long and Altitude) will be
                                                                                                          attached to image transmission
          Configure Color
   (2 bit, 4-bit, 8-bit grayscale,                                              Yes
        12-bit, 16-bit color)


     Configure Resolution
   80x64, 160x128, 320x240,
           640x480
                                                                          Last Packet?
                                                   No
                                                                  No                          Yes
  Configure Data Package Size


   Configure Light Frequency                              Increment Packet ID         Clear Image Transfer
                                                          and sent to Camera          In Progress Indicator
    Compile command with
  configurations to take picture

 Set Image Transfer In Progress
           Indicator


Save Latitude, Longitude, Altitude
for Transmission back to Ground
                                           Return to Main Code                        Reinitialize Packet ID

                                                                                                                                            31
                         Slave: Received Command Handling
                       Receive Data from Ground
                                Station                                                • The ID is one byte of data
                                                                                         specifying what the MCU
                                                                                         should do with the following
                            What is the ID?
                                                                                         data.
                                                                                       • Two main options:
                                                                                          • Next Target
    Next Target                           Go into emergency mode.
                                                                                          • Emergency Mode
                                                                                              • Manual Control
Set next heading and
  target variables             Manual Control Initiation
                                                            Turn off engine and trim          • Turn off Engine
                                                                control surfaces



                                 Goto Manual Control          Goto engine shutoff
                                       Handler                     handler




                   Send data back specifying receipt
                    of transmission and successful
                         change with original ID




                                                                                                                    32
               Software Design: Master
•   Master vehicle acts as client to ground station and as server to slaves
     •   Ground station initializes master service requests
     •   Master initializes slave service requests
           •   Get image
           •   Get telemetry
           •   Download targets

•   Chosen Network Topology:
     •   Ground to Master: Point-to-Point
     •   Master to Slave(s): Point-to-Multipoint        2.4Ghz Zig-Bee




          2.4Ghz Radio
          Modem




                                                                              33
                  Master Software Design
                                                                           Initialization
                                                   Baud Rate
                                                                            Init UART0
                                                     Parity                                           Power-On
•   Interrupt-driven operation ensures              Data Bits               Init UART1

    that both radios are serviced by                Address
                                                                            Setup SR
                                                   Packet Size
    master vehicle                                 Power, etc                ZigBee

•   Master waits in idle most of the time           Address
                                                                            Setup LR
                                                   Packet Size
     • Ground issues data request                  Power, etc                Modem


     • Interrupt occurs from serial                                      Enable UART0/
         data being received                                             UART1 Interrupt


     • Master accumulates packet
                                                                               IDLE
     • Performs decision
     • Issues commands and data
         requests to slaves                      GS Receive Interrupt                        Slave Receive Interrupt
                                                   Service Routine                              Service Routine
     • Slave response causes                       Read UART0                                     Read UART1           Image Data
                                                       Buffer                                        Buffer             Telemetry
         interrupt                                                        Slave ID
                                                      Parse out
     • Cycle repeated…
                                                                        Target Spec:
                                                       packet             XYZ, H                    Assemble
                                                                         Command                 Outgoing Packet
                                                     Assemble
                                            NO    Outgoing Packet
                                                                                            NO


                                                       Ready to                                     Ready to
                                                        send?                                        send?


                                                         YES                                          YES

                                                   Transfer Data                                  Transfer Data
                                                     to UART1                                       to UART0
                                                                                                                               34
               Software: Data Transmission Model
•   Need to optimize packet size to
    meet < 2 sec image delay
    requirement
•   Zig-Bee data frames have at
    least 120bits overhead

          Packet too small – Overhead Dominates             Packet too big – Wasted Idle Time




                            Optimal Packet Size – Delay Approaches 115kbps limit




                                         Total Image Delay Time
                                                                                                35
  Software: Packet Length Optimization
• Transmission time does not meet requirement for
  very short or very long packets.
• Optimal packet size: 50bytes




      Maximum Zig-Bee Packet Size
                                                36
        Software: Ground Station
• Ground station runs MATLAB GUI which controls LR radio
• GUI allows user to enter target information, visualize slave
  telemetry and take pictures




                                                                 37
Integration & Testing




                        38
Systems Integration and Validation
       Integration and Testing Progression
                   Level 1: Isolated Component Testing
             Performance verification of individual components

               Subsystems Integration
               Integrate isolated components into relevant subsystems


                 Level 2: Subsystems Integration and Testing
     Aircraft, Control System (slave vehicle), Imaging, Communications


               Systems Integration
               Integrate individual subsystems into complete system



                  Level 3: Systems Integration and Testing
                         Test systems functionality

               Integrated System Validation
               Validate complete integrated system performance


                  Level 4: System Validation and Verification
  Validate integrated system performance and verify mission objectives met


                                                                             39
           Level 1: Component Testing
Aircraft                                        Communications
Slave avionics and propulsion test              Autopilot (Zig-bee) transceiver test
Range and battery discharge verification        Master communications link
Long period axial oscillation frequency         Ground station communications link
Flight test (GPS speed/altitude verification)   Verify GUI (display slave altitude,
Sig Rascal performance verification             speed, current target image)
(GPS speed/altitude verification)



Autopilot                                       Imaging
Particle vector field simulation                High frequency motor vibration
Simulink vector field simulation with Stryker   Camera resolution determination
Simulink vector field simulation with Miglet    Rotational blur (spinning table)
Flight test Miglet (autonomous control)         Camera data output rate
                                                JPEG compression error




                                                                                       40
           Level 2: Subsystems Testing
Aircraft                                        Communications
Slave controllability                           Verify air-to-air & air-to-ground comm.
    - RC from ground                            Verify transceiver ranges
Master flight capability with slaves attached   Quantify bit error in data transmission
Slave deployment from master (simulated)             -Ground/master, master/slave
                                                Determine transmission time between
                                                ground and master, master and slave



Autopilot                                       Imaging
Generate target vector field for GPS coord.     Take image per autopilot instruction
sent from external comm. link                   Compress image to JPEG
Command elevon servos to execute flight path    Pass image to slave transceiver
Instruct camera to take image
Receive images from camera, tag picture data
with telemetry and pass to comm. link




                                                                                       41
Level 3: Integrated System Validation
                          Flow Up Integrated System Testing

Ground/ Master
•  Ground station to master comm. link
     •   Ground station sends GPS coordinate to master/ master receives GPS coordinate
•   Master to ground station comm.
     •   Master sends picture and telemetry data to ground station and


Master/Slave
•  Master sends GPS coordinate and is received by slave
•  Slave sends picture and telemetry data to master

Slave/Autopilot
•   GPS coordinate received by autopilot (Zigbee)
     •   Autopilot generates flight path and target vector fields
•   Autopilot communicates with elevons and ESC to actively control slave to follow flight path

Autopilot/Camera
•  Autopilot instructs camera to capture image
•  Camera compresses image and passes to autopilot (RS232-to-Zig-bee)
•  Image relayed to master

**Complete Integrated Systems Test

                                                                                                  42
Level 4: System Requirements Verification
   Aircraft
   • 3 targets imaged in under 8 minutes from acquisition of first GPS coordinate
         • 99% probability of detection (Johnson Criteria)

   Communications
   • Image and telemetry data received by GUI within 2 sec of time captured

   Autopilot
   • 3 target locations navigated to and over flown with 99% probability of
   detection (Johnson Criteria)
         •< 15 degree heading error at time of imaging
         •< +/- 6 m deviation from intended altitude
         •< +/- 5 m/s derivation from intended flight speed at time of imaging

   Imaging
   • Image 3 targets each with 99% probability of detection (Johnson Criteria)
   • Images have sufficient resolution that a human can discern 1 x 0.5 x 1.5m
   object




                                                                                    43
                              Systems Integration Flow Chart
                                              Aircraft                  Aircraft/Comm.           Aircraft/Comm./       Aircraft/Comm./Autopilot/
           Aircraft
 -Slave avionics/propulsion          -Slave controllability (RC       -Ground station to            Autopilot                   Imaging
  -Slave battery discharge           from ground)                     master comm. link        -GPS coordinate         -Autopilot instructs camera to
       -Slave stability              -Master flight capability        -Master to ground        received by autopilot   capture image
   -Master/Slave flight test         with slaves                      station comm.            (Zigbee radio)          -Camera compresses image and
                                     -Slave deployment                -Slave to master comm.                           passes to autopilot (RS232-to-
                                     (simulated)                      link                                             Zig-bee)
                                                                                                                       -Image relayed to master




    Communications                     Communications
-Master/slave comm. link          -Verify air-to-air/ air-to-ground
verification                      comm. links
-Ground station com. link         -Verify transceiver ranges
verification                      -Determine bit error in data
                                  transmission
                                                                                                                                    Aircraft
-Verify GUI display
                                                                                                                       -3 targets imaged in under 8
                                  -Determine data transmission
                                                                                                                       -99% probability of detection
                                  times

                                                                                                                              Communications
                                                                                                                       -Image data received by GUI
          Autopilot                                                                                                    within 2 sec of time captured
                                            Autopilot
-Particle vector field sim.
                                  -Generate target vector fields                                                                  Autopilot
-Simulink vector field
                                  -Command of elevon servos
simulation (Stryker)                                                                                                   -3 target locations navigated to
                                  -Instruct camera to take image
-Simulink vector field                                                                                                 and over flown with 99%
                                  -Receive image data from
simulation (Miglet)                                                                                                    probability of detection
                                  camera and pass to comm. link
-Autonomous control flight test
(Miglet)                                                                                                                           Imaging
                                                                                                                       -Image 3 targets
                                                                                                                       - Images have sufficient resolution
                                                                                                                       that a human can discern 1 x 0.5 x
                                                                                                                       1.5m object
           Imaging
-High frequency motor                         Imaging
vibration                         -Take image per autopilot                                    Level 1: Component Testing
-Verify camera resolution         instruction
-Rotational blur test             -Compress image to JPEG                                      Level 2: Subsystems Integration
-Camera data output rate          -Pass image to slave
-Camera JPEG compression          transceiver                                                  Level 3: Systems Integration
pixel error
                                                                                               Level 4: System verification


                                                                               Time
                                                                                                                                                             44
Project Plan & Management




                            45
     Project Management Overview
•   Organizational Chart
•   Work Breakdown Structure
•   Critical Path Elements
•   Budget Predictions/Expenditure




                                     46
Organization
                                                     Organization Chart

                                                                     Project
                                                                     Manager
                                                                    Matt Edwards

                                                                 Assistant PM
                                                                    John Shelton

                                                                                            Financial Officer
                                                                                               Galina Dvorkina
                                   Safety Officer
                                        Eric Kohut
                                                                                               Webmaster
                                                                                                  Nick Driver

                                                              Systems Engineer
                                                                    Arseny Dolgov


                                                                                                Avionics:
                Controls:             Aircraft Design:                   Imaging:                                           Verification:
                                                                                                  Power
                 Autopilot              Aerodynamics                      Cameras                                         Testing Procedures
                                                                                                 Software
                Navigation               Performance                       Optics                                        Requirements Review
                                                                                               Communication



      Lead                       Lead                        Lead                       Lead                          Lead
  Johnny Janetto             Kevin Eberhart               John Shelton               Nick Driver                   Eric Kohut



    Assistant                  Assistant                   Assistant                  Assistant                     Assistant
  Matt Edwards               Johnny Janetto              Kevin Eberhart             Galina Dvorkina              Galina Dvorkina



                               Assistant                   Assistant                  Assistant
                              Eric Kohut             Galina Dvorkina                Arseny Dolgov


                                                                                                                                               47
                        Work Breakdown Structure

                                                                               Work Breakdown
                                                                                  Structure




  Project                                                           Fabrication                                                      Vehicle
                                    CFO                                                             Imaging                                                               Controls
Management                                                           Engineer                                                       Dynamics

    Scheduling                      Funding/Budget                   Create Necessary                Camera Selection                    Aircraft Selection               Autopilot Selection
                                     Management                       Solid Models
 Group Management                                                                                   Imaging Geometry:                    Aircraft Config.                  Control Modeling
                                                                        Fabrication                  FOV and Working
                               Track Expenditures
 Task Management                                                       Requirements                     Distance                             Stability                    Servo Requirements

 Task Management               Team Procurement                     Materials Selection              Detection Criteria                   Aerodynamics                      Attitude Sensors
                                    Adhere to Fiscal                   Machining &                     Processing &
 Customer Relations                                                                                                                        Performance                    Stability Performance
                                       Policies                        Manufacturing                     Retrieval

                                                       Safety&
                  Systems
                                                         Test                       Webmaster                         Software                              Power                                 Comm
                 Engineering
                                                       Engineer

                      Requirements                      Maintain Facility                 Update Website                  Microcontroller                     Battery Selection                      Transceiver
                       Flowdown                         Safety Standards
                                                                                       Maintain Document                    Autopilot                          Power Budgets                      Bandwidth Budgets
                      Subsystem                         Advise on Safety                     Server
                      Integration                         Procedures                                                      Ground Station                      Motor Selection                        Frequency
                    Mission Design                      Ensure Team &                                                        Protocols                        Distribution and                         Range
                                                       Environment Safety                                                                                       Regulation
                   Risk Assessment
                                                                                                                                                                                                      Interfaces
                                                       Create and Maintain
                                                       all Test Procedures




                                                                                                                                                                                                                   48
      Critical Path Elements
• Defined as elements with highest
  unknown time requirement and risk
  which are heavily depended on
  elsewhere in the project.
  •   Imaging Software/Interface
  •   PCB Verification
  •   Control Software/Algorithms
  •   Communications Software




                                      49
                               Budget Analysis
                   Category          Name/Item Description      Unit Price ($)   Quantity   Total Cost   Purchased     Amount ($)

                   Controls          Microcontroller Unit       $        20.00          3   $   60.00

                                     GPS (Units)                $        75.00          2   $ 150.00

                                     Rate Gyros                 $        50.00          3   $ 150.00

                                     Radio Development          $       120.00          1   $ 120.00

                                     Radios                     $        35.00          2   $   70.00

                                     Receiver                   $        60.00          3   $ 180.00

Total Available:                     Autopilot                  $       500.00          1   $ 500.00

$5,900.00                            PCB Manufacturing          $       100.00          3   $ 300.00

                   Vehicles          SIG Rascal                 $       399.99          1   $ 399.99

                                     Motor                      $        40.00          1   $   40.00

Funding:                             Slave Plane                $       150.00          3   $ 450.00       3-Nov-06    $     99.99

•Senior Project                      Glue                       $         8.00          1   $    8.00      3-Nov-06    $      7.99

                                     6 Channel Radio            $       180.00          1   $ 180.00       3-Nov-06    $     34.99
    Funds: $4000                     Battery                    $        60.00          3   $ 180.00       3-Nov-06    $     39.99
•EEF: $1900                          Battery Charger            $       100.00          1   $ 100.00       3-Nov-06    $     36.48

                                     Electronic Speed Control   $        85.00          3   $ 255.00

                                     Servo                      $        15.00         10   $ 150.00       3-Nov-06    $    159.99

                                     Servo Extension Wires      $         5.00          1   $    5.00      3-Nov-06    $      4.29

                   Power             Slave Motor                $        40.00          3   $ 120.00

                                     Speed Control              $        40.00          1   $   40.00

                                     Battery Charger            $        50.00          1   $   50.00

                                     Voltage Regulators         $        50.00          3   $ 150.00

                   Communications    Modules                    $       199.95          2   $ 399.90

                   Imaging           Camera                     $        50.00          3   $ 150.00

                                     Evaluation Board           $        50.00          3   $ 150.00       5-Nov-06    $     55.80

                   Sub-Total                                                                $4,357.89    Total Spent   $    439.52

                   TOTAL with 25% Margin                                                    $5,810.52    Total Left    $   5,480.48
                                                                                                                                      50
Appendix




           51
                     Electrical Design: Communications
              • Network topology trades:
              • Server-client point-to-point direction connection network
RADIO MODEM


                 •    Suitable for high-data rate
                 •    Minimal protocol and handshaking overhead
                 •    Long ranges possible
                 •    Simple to design, robust
                 •    Minimal required CPU intervention
              • Server to multiple-client point-to-multipoint connection
                network
                 •
ZIG-BEE




                      Suitable for medium data rates
                 •    Lots of protocol and handshaking overhead
                 •    Short-range
                 •    More difficult to design
                 •    Allows for more complex networks with multiple clients




                                                                               52
                 Testing Plan
•   Testing and Verification Tree
•   Requirements Verification Breakdown
•   Order of Testing
•   Component Verification
•   Major System Test Procedures




                                          53
                        Testing and Verification Tree
                                           SOARS System
                                              Mission




                                  System
                               Communications




       Ground Station                            Slave Vehicle                       Master Vehicle
          System                                    System                             System




 Software          Interface     Power             Imaging                              Power
                                                                      Autopilot
Subsystem         Subsystem    Subsystem          Subsystem                           Subsystem




                                                 Algorithms and
                                                                                        Attitude
                                                Control Software   GPS Positioning
                                                                                     Determination
                                                   Subsystem

                                                                                                      54
Master Vehicle Requirement Verification
                                                                  Slave Vehicle




 Control                                    Communications                                Power                                   Imaging



            Pitch within 30°                                 Bandwidth                                                                        Resolution
                                                                                                  Range > 4 km
             Rate < 12°/s                                    > 250 kbps                                                                       > 600 lines


                                Simulation                                File Transfer
                                                                                                              GPS Verification                               Resolution Test
                               Flight Testing                                  Test


             Roll within 30°                             < 2 Seconds
                                                                                                  Speed > 30 kph                            30° < FOV < 60 °
             Rate < 115°/s                               Image Delay


                                Simulation                                Image Capture                                                                     Field of View Test
                                                                                                                 Flight Testing
                               Flight Testing                                Timing                                                                           Flight Testing


           Heading within 30°                                                                                                               Working Distance
             Rate < 12°/s                                                                                                                        < 90m


                                Simulation
                                                                                                                                                              Flight Testing
                               Flight Testing


           Position Accurate
                To 10m


                          GPS Verification
                               Test


                                                                                                                                                                           55
Master Vehicle Requirement Verification
                              Master Vehicle



       Avionics                                                        Power


                  Data Relay > 250 kbps                        > 20 Minutes Operating
                    > 2 Second Delay                            Time for Avionics and
                                                                   Comm System

                                         File Transfer Test
                                       Image Capture Timing
                                                                          Battery Testing
                                                                     Flight Testing Verification
                     Must Fit Inside
                     5x10x5 cm Box


                                         Size Verification



                      Range > 2 km



                                       GPS Verification Test


                                                                                                   56
Ground Station Requirement Verification
                                      Ground Station



 Graphical User
                                      Communications                          Control Software
   Interface


              GPS XY Input                         Receive Data                             GS – Master
              Heading Input                          at 1 Hz                                Handshaking


                                                               Data Transmission                      Ground Station
                         Software Testing
                                                                      Test                            Static Testing


            Display 640 x 480                                                               Ensure Slave
                                                   Range > 2 km
            Resolution Image                                                             Receives Command


                                                                                                      Ground Station
                        Image Display Test                      GPS Verification
                                                                                                      Static Testing


              Display Slave                            Bandwidth
               Telemetry                               > 250 kbps



                         Software Testing                       File Transfer Test


                                                                                                                       57
             Testing Progression

                             Component Level Testing

                   Slave          Battery
Resolution                                       Ground Station       Communications                  Miglet Initial
                 Vibration       Endurance
 Testing                                         Display Testing      Range Verification             Flight Testing
                  Testing         Testing




                             Sub System Level Testing

                                                                            Software
 Imaging                      Motor                  Power                                               Autopilot
                                                                          And Interface
 Testing                     Testing                 Testing                                              Testing
                                                                             Testing



                                System Level Testing


                         Ground
                                         Master            Slave
Communications           Station                                      Static Test           Test           Mission
                                       Integration     Integration
  System Test           Operation                                      Mission             Mission         Success
                                       Flight Test      Flight Test
                          Test




                                                                                                                       58
              Major Systems
• Ground Station System Test
  • Goal: To verify proper operation of the User Interface and
    display software
• Master Vehicle System Test
  • Goal: To verify proper operation of the Master Vehicle’s
    communications system and handshaking ability in
    conjunction with the Ground Station
• Slave Vehicle System Test
  • Goal: To verify proper operation of the Slave Vehicle’s
    integrated subsystems in conjunction with the Ground
    Station and the Master Vehicle
• Communications System Test
  • Goal: To verify proper operation of the communications
    system prior to integration with the SOARS system



                                                                 59
                   Ground Station System Test


• Procedure
   •   Place master and slave within
       LOS of the ground station
   •   Have ground station request
       image from slave through the         • Test Location: Arvada
       master                                 Associated Modelers Club
   •   Record time requested and
       time elapsed to ground station
       display
   •   Verify location of the slave and
       master with handheld GPS                  Stationary
       receiver


                                          2 km                 1 km



                                                               Stationary

                                                                            60
               Master Vehicle System Test


• Procedure
   •   Launch the master and place
       on station 2 km from the
       ground station and place the
       slave within LOS of the
       master
   •   Have ground station request
       image from slave through the
       master
   •   Record time elapsed to
       ground station display
   •   Ensure flight endurance of 20
       minutes
                                     2 km
                                              1 km




                                            Stationary

                                                         61
                   Slave Vehicle System Test



• Procedure
   •   Launch master and slave and
       place on station at 2 km and 1
       km, respectively
   •   Have slave conduct target run
       on field setup
   •   Record time elapsed to
       ground station display
   •   Ensure slave flight endurance
       of 10 minutes
   •   Observe test images




                                               Target
                                                        62
              Communications System Test

•   Connect Test Procedure
    •   Use internal testing option of
        communications system
        program
    •   Plug both radios into two
        different USB ports on the
        same computer
    •   Run test program for 10
        minutes
    •   Save file
    •   Repeat test for varying time
        and test settings (continuous,
        break on error)
•   Range Test Procedure
    •   Plug both radios into two
        different USB ports on two
        different computer
    •   Place computers 2 km apart at
        test field and verify distance
        through a handheld GPS
        receiver
    •   Run same settings as in
        previous test to ensure proper
        operation for communications
        system
                                           63
                    Hardware Integration Flow Chart
Slave:

   3 Cell/ 910mAh     6 Ch Futaba                                                                 380 Brushed motor
                                         Autopilot              ESC             Throttle Servo
   LiPo Battery       receiver                                                                    (Ducted Fan Unit)



                                                             Elevon Mixer        Elevon Servos


                                         Imaging
                                         (camera)


Master:

   Futaba 6EXS      Futaba 6 Ch.           ESC                 Throttle Servo
   Controller       receiver



                    Elevator/Aileron                                - Blue boxes denote isolated subsystem components
                    Servos                                            - Orange boxes denote primary integrated subsystems



   GUI
                    Ground Transceiver               Slave
   (Laptop)




                                                                                                                      64
               Imaging: Camera Choice




Study Results: the C328-7640 Camera Module will be our initial imager

                                                                        65
   Imaging: Specific Requirements
• We can now calculate maximum
  imaging range using Johnson Criteria
  (80 m)
• Given this range, we can calculate
  maximum pitch, yaw, roll, and velocity
  and ensure our chosen airplane
  conforms to these requirements in its
  planned flight path
   •   Max tangential velocity: 60 m/s
   •   Max radial velocity: 80 m/s
   •   Max pitch/yaw: 0.2 rad/s
   •   Max roll: 2 rad/s




                                           66
          Imaging: Fulfillment of Requirements
• We will fly our airplane at a cruising speed of 17 m/s (40 mph)
  directly over the target, imaging at just under max imaging
  range
• Altitude: 45 m (allows for error in altimeter)
• Satisfies all blur requirements
   • Pitch Rate: 0.1 rad/s (<0.2 rad/s)
   • Yaw Rate: 0 rad/s by definition of flight path
   • Roll Rate: 0 rad/s by definition of flight path
   • Radial Velocity: 8 m/s (<80 m/s)
   • Tangential Velocity: 15 m/s (<60 m/s)
• Imaging window time of 3 seconds




                                                                    67
                        Power – Ducted Fan Test
• Measured Baseline Normal and Axial
  Forces in Wind Tunnel with Motor Off
• Measured Forces With Motor On
• Results Inconclusive
  • Reexamine Test Set Up
                                                   Axial Force                   Motor Off
                                                                                 Motor Running
                       1
                      0.9
                      0.8
                      0.7
    Axial Force (N)




                      0.6
                      0.5
                      0.4
                      0.3
                      0.2
                      0.1
                       0
                            1
                                8
                                    15
                                         22
                                              29
                                                   36
                                                        43
                                                             50
                                                                  57
                                                                       64
                                                                            71
                                                                                 78
                                                                                      85
                                                                                           92
                                                                                                99
                                                   Reading Number
                                                                                                     68
                                    Power - Backup
• Normal Force Plot
                                                                      Motor Running
                                              Normal Force
                                                                      Motor Off
                       1

                      0.9

                      0.8

                      0.7
   Normal Force (N)




                      0.6

                      0.5

                      0.4

                      0.3

                      0.2

                      0.1

                       0
                            1   8   15 22   29 36   43 50   57 64   71 78   85 92   99
                                                Reading Number



                                                                                         69
                                     Power – Motor Test
                  • Measure Ducted Fan Forces and Motor Power
                    Consumption
                        • Speed 370 Brushed Motor
                        • 0.8 W Resistance
                        • 5.5 Minutes
                                 Motor Power Consumption

            120


            110


            100
Power (W)




            90


            80


            70


            60
                                    0

                                    0

                                    0

                                    0

                                    0

                                    0

                                    0

                                    0

                                    0

                                    0

                                    0

                                    0
             10

                  30

                       50

                            70

                                  90
                                 11

                                 13

                                 15

                                 17

                                 19

                                 21

                                 23

                                 25

                                 27

                                 29

                                 31

                                 33




                                            Time (s)

                                                                70
              Power - Conclusions
   • Need to Increase Battery Capacity
      • Current – 910 mAh (stock) lasts 5.5 min
      • Need – 1800 mAh for >8 min
      • Found Pro Lite 11.1 V, 20C discharge
        battery



 Battery       Capacity   Mass (g)    Volume (mm)
 ElictriFly
               910 mAh      79        20 x 34 x 62
GPMP0815
 Pro Lite
               2000 mAh     120      19 x 47.6 x 63.5
 TP20003



                                                        71
Electrical Design: Master UAV Comm Board




                                           72
Electrical Design: Slave UAV Daughter Board




                                              73
                        Project Risk

                                       Software
                                       Failure


                                                      Cannot control aircraft
                                                      to requirements




 Failure of
 communications relay                                    Microcontroller cannot
                                                         handle all operations

                        Battery endurance
                        not to requirement


                                                  Unable to take picture
 Payload Mass
                                                  in desired location
 too High




LOW                                               Medium
           High
                          Impact on System

                                                                                  74
       Facility Requests
• Wind Tunnel
  • Dynamic thrust test and battery power
    testing.
• Table Mountain Radio Quiet Zone
  • Secured for flight testing of slave,
    master and ground system.
• Aerospace Electronics Lab




                                            75
        Schedule Overview
•   Aircraft Selection and Stability
•   Power and Electrical
•   Imaging
•   Controls
•   Communications
•   Software/Electrical Hardware
•   Safety/Testing
•   Management
•   Presentations/Documentation

                                       76
Schedule (Slide 1)




                     77
Schedule: Software (Slide 2)




                               78
Schedule: Integration and Testing




                                    79
Schedule: Project Management




                               80
  Control System Requirements

• Path Tracking
• Altitude Control
• Slave
  - Path tracking to allow imaging
    of target
• Master
  - Circular loiter




                                     81
  Control System Selection
• Using existing graduate student
  board
• Modifying autopilot
  • Consists of developing new vector field
  • New model and controller to fit different
    aircraft




                                            82
    Design and Verification Process
•   Design of vector fields for trajectory tracking
•   Verifying vector field via particle simulation
•   Model aircraft dynamics and controller design
•   Verification of system via Simulink Model
•   Flight Test




                                                      83
Vector Field Design
               •Globally attractive
               •Field switched for
               individual targets




                                      84
           Master Vector Field
• 300m Diameter Loiter Circle
                         Master Vector Field Particle Simulation
    800



    600



    400



    200



      0



    -200



    -400
           -400   -200       0        200       400      600       800   1000




                                                                                85
       Altitude Control
• Throttle Control
• Elevon Control
• Combination




                          86
           Camera Mounting
• Camera module is embedded in the foam wing, far enough
  away from the fuselage to prevent blocking the FOV




          PCB and CMOS sensor

      Camera Lens
                                Pylon Attachment Point
                                                           87
       Slave UAV Interconnect Diagram
                                                                      Power
                                                                      Data
                              Battery
                              -    +
                                    16 gage high-current wire


              4-Channel                          PWM
              Bus                                Bus

RC Receiver                 Autopilot                           ESC           Motor


                                                                  Servos
                          Camera Power &
                           Interface Board
                                        Asynchronous
                                        Serial Bus

                           Camera Module
         Master UAV Interconnect Diagram
      2.4 GHz Antenna 1                          2.4 GHz Antenna 2
                                                                         Power
                                                                         Data
                            Comm Board
              RF Coax                         RF Coax




                             Battery
                             -    +
                                  16 gage high-current wire


                4-Channel                      PWM
                Bus                            Bus

RC Receiver                 Autopilot                         ESC                Motor


                                                                Servos

				
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