Docstoc

Gp9FinalCDR

Document Sample
Gp9FinalCDR Powered By Docstoc
					Advanced Remote Monitoring and
    Operated Recon Device
       Andrew Lichenstein
       Kevin Jadunandan
         Thomas Kehr
Special Thanks




                 2
Motivation
Dragon Runner surveillance robot
  Extremely Durable
  Fast and lightweight platform
  ≈$32,000 per unit


Objectives:
  Fraction of the Price(< $2500)
  Maneuverability on all terrains
  Wireless Control/Video
          iPhone Control




                                     3
Hardware Block Diagram




                         4
Specifications
Physical
Length               18 in.
Width                14 in.
Height               10 in.
Weight               57 lb.

Power
Motor Battery         24V
Control Battery       12V

Communication
Video Frame Rate      30 fps
Operating Distance    100ft

Locomotion
Peak Speed            6 mph
Wheel Size            10 in.
Motor RPM             252 rpm
Turn Radius           0°
                                5
Chassis

  Raw Material Selection

  Suspension

  Body Design

  Component Mounting

  Camera



                            6
Chassis: Raw Material Selection
Aluminum                                Plastic Composite
    Low-cost                                  Extremely High Cost
    Light weight                              High Strength
    High cost of manipulation                Light Weight
                                              Requires Computer Generated Design
Fiberglass Composite                     Carbon Fiber
    Extremely low cost                       High cost
    Easily manipulated                       High Strength
                                              Complex manipulation
    High Strength
    Experienced with fabrication
    Permeable to Radio frequencies


                                      Fiberglass     Carbon Fiber      Aluminum
      Ultimate Strength (MPa) 3,450                  5,650             40-50
      Yield Strength (MPa)            N/A            N/A               15-20
      Density (g/cm3)                 2.57           1.75              2.7
      Average Price ($/ft)            0.91           13.80             7.50
                                                                                    7
Chassis: Suspension
Aluminum Frame – 1/8” Aluminum Sheet
   Provide mounting for components
   No metal on metal; rubber washers
Spring Suspension System
   32 Springs
   8 Motor Clamps




                                        8
Chassis: Body Design
Fiberglass-Composite Construction

Clam-Shell Design

Plug and Mold Fabrication

                                          20”




                                     7”


                                           17”
                                                 9
Chassis: Component Mounting




      Camera     Circuit Board and Motor Controller




                                                      10
Chassis: Polyurea

Truck Bed Liner
  Rhino Liner, etc.
Extreme Durability
  41 MPa Tensile Strength
Quick Reaction Time
  Build up Multiple Layers
Explosive and Ballistic resistance




                                     11
Drive Train


  Geared Motor

  Wheels and Locomotion




                           12
Drive Train: Motor Selection

IG42 Geared Motor
    24:1 Gear Ratio
    24V DC
    252 rpm
    2300mA
    10 kgf-cm Torque
                        1.75”




             4.8”
                                13
Drive Train: Wheels and Locomotion

Wheels
  Wheel + Tire
  10” Diameter
  Custom Mounting Hardware


Wheel Speed
  Speed (fpm) = (Diameter of wheel (in) x π x rpm of
   motor) /12
  = (10” x π x 252) /12 = 659.7 ft/m
  = 7.59 mph

                                                        14
Power System


   Batteries

   Charging Circuit

   Control Battery

   Drive Battery




                       15
Power System: Batteries

NiMH Rechargeable Packs
  24V 4500 mAHr
    Drive Battery
  12V 4000 mAHr
    Control Battery




                                       5" x 2" x 2"


                       10" x 2" x 2"



                                                      16
Power System: Charging Circuit

DPDT Switch
  Toggles Between ON-OFF-Charge

Military Style Locking Connector




                                   17
Power System: Control Battery
      Component        Current    Operating     Power
                       Draw       Voltage       Consumption
      XBee Pro         55ma       3.3V          0.18 Watts

      Falcom FSA03     40ma       3.3V          0.132 Watts

      PIC18F4520       200ma      5V            1 Watt

      Wireless         500ma      9V            4.5 Watts
      Camera
      Total            795ma                    5.812 Watts



                           Capacity = 4 AHr

                      Current Drain of system =
                               795mA

                     Estimated battery life ≈ 5 hrs



                                                              18
Power System: Drive Battery

  Component           Current Draw    Operating   Power
                                      Voltage     Consumption
  IG42 Geared Motor   2300mA          24V         55.2Watts




                  Battery Capacity= 4.5 AHr

              Current Draw= 2300mA x 4 = 9.2 A

                  Battery Life = 29.3 minutes




                                                                19
Video System: Camera

380-lines resolution

150-foot range (no
obstacles)
900 MHz output
frequency

Built-in microphone




                        20
Internal Hardware

  MCU

  GPS

  Communication

  Motor Controller




                      21
    Internal Hardware: MCU
Features our group looked for in MCU:
    CPU Speed >= 4MIPS (10 MIPS)
                                           PIC18F4520
    Program Memory >= 16KB (32KB)

    Internal Oscillator >= 4MHz (16MHz)

    IO Pins >= 15 (30)

    ADC >= 2 (15)

    Program in C/C++ using MPLAB IDE

    Temperature Range (-40 to 125 C)

    PDIP

*PIC18F4520 Max Spec’s in ()
                                                        22
Internal Hardware: MCU
  Communication is the most essential part of our
   robot, we will need to be sending and receiving data
   from our Gateway to be able to control our robot.
   We will be using the hardware USART pins on the
   MCU, which allows us to send serial data reliably.
  Our MCU will need to be data parse incoming GPS
   updates which come in the form of a string of
   characters. We will be emulating the hardware by
   emulating the hardware, using software USART.
  Motor Control will be done by having two variables
   set , one for the left motors and one for the right
   motors. We will be sending a value of 0 to 255,
   which will tell which motor to move and how which
   direction it should spin the motor. This also will be
   using software USART.
  Battery life and Temperature value will be done
   using AD Converters of the MCU, which takes
   voltage as inputs.

                                                           23
Communication: Options

XBee vs. XBee Pro vs. Bluetooth Class 1


               XBee      XBee Pro   Bluetooth   The Bluetooth was a bit
                                     Class 1    to expensive and the
Indoor Range    Up to      Up to    Up to 330   regular XBee distance
                100ft      300ft        ft      was a bit to small. This
Outdoor/LOS     Up to     Up to 1   Up to 330   is why we chose the
                300ft      Mile         ft      XBee Pro which was a
                                                good combination of
Data Rate      250Kbps   250Kbps     Up to 3    both data rate and
                                      Mb/s      distance. We really only
Unit Price     $22.95     $37.95     $59.95     need 300 to 400 ft max
                                                for our application.



                                                                    24
Internal Hardware: GPS

We originally were looking at the Copernicus GPS
Module that was sold on Sparkfun, but after talking
with other sources they pointed out to me the Falcom
FSA03 unit. Here are the details of the unit:


               Copernicus     Falcom
 Cold Start      39 sec        29 sec
 Hot Start        9 sec       <1 sec     One of the best features of this
 Antenna       Not Included   Attached   chips is that it has a Sarantel
 Update Rate       1Hz          4Hz      helical antenna which lets you
                                         orient this GPS any way you
 Channel           12           32       would like , so you don’t have
                                         to make it point towards the
                                         sky.
                                                                       25
Internal Hardware: Temperature Sensors

The TMP35 outputs a voltage based off the current
temperature around the sensor. Using the linear equation
below, we can get the temperature on our microcontroller
and motors.
         Temp in °C = [(Vout in mV) - 500] / 10




                                                           26
Internal Hardware: Battery Life

Using two simple voltage divider circuits to lower the
voltage to a max of 5 volts, we check the battery voltage
every other second. Knowing our fully charged voltage we
can make an assumption on our remaining voltage as the
voltage gets lower.




                                                            27
    Communication: GPS Purpose

    The GPS’s main purpose was to be sending latitude
    and longitude to our microcontroller so that we could
    use this data with our iPhone application. The GPS
    sends NMEA(National Marine Electronics Association)
    data to our MCU; here is an example of what it looks
    like:
           $GPGLL,4916.45,N,12311.12,W,225444,A,*1D

Geographic Lat & Lon              123o11.12         Data Active

                                              Time(UTC)           Checksum
                       49o16.45
    As you can see the data that is sent is not an easy to
    read format so our MCU will parse the data needed and
    send to a variable that will be sent out via XBee.
                                                                      28
Motor Controller: Selection
Originally we were thinking of
creating our own motor controller
using PNP BJTs but due to the fact
we wanted stability and more
features we decided to buy the
Sabertooth 10A Dual Motor
Controllers. One of the key
features that we really liked as a
group was that it is a regenerative
motor driver, so when the robot
stops or reverses it recharges the
batteries with the wasted energy. It
also has over current and thermal
protection which means we won’t
have to worry about damaging the
motor controllers.
                                       29
Motor Controller: Setup
  In our setup we will be using two
   motor controllers in parallel. So
   we will be using one pin on our
   MCU a Tx line that uses software
   USART that connects to the S1
   ports on the motor controllers.

  The Tx line on the MCU will
   transmit to both of the motor
   controllers S1 lines at the same
   time. We will be sending values of
   0 to 255 to the motor controllers .

  A value of 1 to 127 controls the left
   motors and a value of 128 to 255
   controls the right motors
                                           30
MCU Software Diagram


RECEIVE THREAD                      SEND THREAD


                 DATA STRUCTURES



                     -Left Motor
                    -Right Motor
                      -GPSLat
                      -GPSLon
                     -BatteryLife




                                             31
Board Design Prototype


  Created in EagleCAD

  Screw Terminals make it
   easy to connect
   peripherals and stop
   wires from falling out




                             32
Custom PCB

 Using a flatbed plotter we make our own single
  sided PCBs for testing purposes. We can create 15
  PCBs for less than $25.




                                                      33
Gateway / iPhone Interface

Software applications

  iPhone Application

  Gateway Application

  Last Minute Add-on: iPad App




                                  34
Software Communication




                         35
Software

iPhone Application
  Primary controlling device

  Touch based interface

  Displays map with location of user and ARMORD




                                                   36
Software

iPhone Application
  Written in Objective C
      Apple’s object oriented version of C
      Runs all C code natively


  Xcode IDE and Interface Builder
      Provides drag and drop UI design




                                              37
Software: iPhone GUI




                       38
Software: iPhone GUI




                       39
Software: iPhone GUI




                       40
Software: iPhone GUI




                       41
Software: iPhone GUI




                       42
Software: iPhone




                   43
Software: iPhone

Distance Calculation
  Uses latitude and longitude

  Distance in miles =
 3963.0 * arccos[sin(lat1) * sin(lat2) +
             cos(lat1) * cos(lat2) * cos(lon2 - lon1)]




                                                         44
Software: Gateway Application

Purpose
  Wireless bridge between the iPhone and the ARMORD

  Necessary because iPhone cannot easily connect to
   the XBee module

  Communication
     Wi-Fi – iPhone
     XBee – Robot




                                                       45
Software: Gateway Application

Requirements
  Wi-Fi connection
  COM port access
Options
  C#
  Java
Decision – C#
  Simple TCP Server and COM Port Access




                                           46
Software: Gateway Application




                                47
Software: Gateway Application




                                48
iPad

Control Scheme
  Turning - Accelerometer based

  Forward/Reverse – Slider

  “Steering Wheel”




                                   49
iPad – Screenshot




                    50
    Software

    Packet Structure
      From iPhone To ARMORD
       $   LEFT_MOTOR   $     RIGHT_MOTOR


      From ARMORD To iPhone

$    LATITUDE   , LONGITUDE    , MOTOR_BAT   , MCU_BAT TEMP ;




                                                                51
Video Transmission – Original Design




  Video is received by video capture card
  Computer broadcasts live stream over Wi-Fi
  iPhone plays live stream

                                                52
Video Transmission – Original Design

Problems
  For live video, iPhone only plays H264 video, with AAC
   audio, encapsulated in an MPEG2-TS

  Capture card software could not output proper video
   format

  10 second video lag from camera to a computer
   watching the stream




                                                         53
Video Transmission – New Design

Solution – External LCD Display
  Allows direct video feed from camera to display
  No processing on a computer to reduce video delay
  iPhone can now display more information on the
   screen
    Maps
    GPS locations
    Distance
    Battery Life




                                                       54
Controller
•Components
     7” Standalone Monitor
     Ruggedized Grip and Frame
     AV Receiver
     12V NiMH Battery

Video and Control up to 100
feet

Components attached to
controller via aluminum
bracket

Power supplied to AV
Receiver and Monitor through
12V NiMH battery

Swivel mount to account for
inversing camera orientation      55
Budget
   Part Name                         Quantity    Price    Total Cost
   12V 2200mAHr NIMH                    1       $23.90
                                                           $23.90
   12V 4000mAHr NIMH                    1       $53.60
                                                           $53.60
   24V 4500mAHr NIMH                    2       $124.80
                                                           $249.60
   Falcom FSA03 GPS                     1       $59.95
                                                           $59.95
   24V 252 RPM Geared Motor             5       $44.90
                                                           $224.50
   IPhone Grip                          1       $25.50
                                                           $25.50
   Sabertooth 10A Motor Controller      2       $79.99
                                                           $159.98
   7 in. LCD                            1       $79.99
                                                           $79.99
   2.4GHz Mini Wireless Camera          2       $42.50
                                                           $85.00
   900 MHz Mini Wireless Camera         1       $60.00
                                                           $60.00
   Truck Bed Liner                      2        $9.95
                                                           $19.90
   XBee Pro                             3       $37.95
                                                           $113.85
   XBee USB Explorer                    2       $24.95
                                                           $49.90
   XBee Breakout Board                  1        $9.95
                                                            $9.95
   PIC18F4520                           3        $4.50
                                                           $13.50
   Misc(Body, Copper Clad, Etc.)       NA       $400.00    $400.00
   Developmental Tools                 NA       $350.00    $350.00
   Shipping/Handling                   NA       $300.00    $300.00
   Total                                                  $2429.14     56
Questions




            ???


                  57

				
DOCUMENT INFO
Shared By:
Categories:
Tags:
Stats:
views:10
posted:7/7/2011
language:English
pages:57