Autonomous Dual Navigation System Vehicle自治的双重导航系统的车辆

1、Autonomous Dual Navigation System VehicleDmitriy BekkerSergei KunsevichComputer EngineeringRochester Institute of TechnologyDecember 1, 2005Advisor: Dr. Roy CzernikowskiProject Design ReviewCE Projects II Rochester Institute of TechnologyOutline Project overview System description Achieving objectiv

2、es Vehicle motors Detailed system view Component interface Operational boundaries Sensor placement User interface System analysis GPS Wireless communication Sensor concerns Where we stand now Budgeting (key components)CE Projects II Rochester Institute of TechnologyProject Overview System Descriptio

3、n Autonomous Dual Navigation System Vehicle A vehicle that can autonomously navigate itself to user specified waypoints while reporting and avoiding obstacles on the way. Vehicle base is a 1:6 model of Hummer H2 Uses two systems for navigation GPS Electronic compass and optical shaft encoder User in

4、terface from base station (through wireless connection) Vehicle can navigate without GPS (when no signal) Obstacles detected with rotating ultrasonic range finderCE Projects II Rochester Institute of TechnologyProject Overview Achieving Objectives Moving to a destination Determine angular orientatio

5、n (compass) and distance to destination Turn towards destination and start moving Tracking vehicle movement With GPS (when available) With compass and optical shaft encoder Obstacles Detected with ultrasonic range finder Need to research suitable obstacle avoidance algorithmsElectronic compass (Deva

6、ntech CMPS03)Optical shaft encoderGPS (Garmin 15L)Ultrasonic range finder (Parallax PING)CE Projects II Rochester Institute of TechnologyProject Overview Vehicle Motors The vehicle will move using: One DC motor for forward / reverse motion of the rear wheels One servo motor to steer the front wheels

7、 The ultrasonic range finder will rotate using a second servo motor Front facing 180 rotationCE Projects II Rochester Institute of TechnologyDetailed System Overview Component InterfacePWM portCE Projects II Rochester Institute of TechnologyDetailed System Overview Operational Boundaries For demo, t

8、he vehicle needs a flat surface with minimum or no surface particles (like snow, ice, rocks, etc) GPS capability can only be demonstrated outdoors Indoors the vehicle can only navigate using compass and optical shaft encoder Compass is sensitive to magnetic fields, so vehicle should be operated away

9、 from large metallic objects and high power electronics Obstacle placement constraints will be determined once a suitable obstacle avoidance algorithm is chosenCE Projects II Rochester Institute of TechnologyDetailed System Overview Sensor PlacementServo motorUltrasonicrange finderservo motorfor tur

10、ningbattery packfor movementmotors GPS receiverNSEWDigitalcompassCE Projects II Rochester Institute of TechnologyDetailed System Overview User InterfaceXX N S W EHeading20Current CoordinatesLAT: dd.mm.secLNG: ddd.mm.sec_Next Waypoint_LAT: dd.mm.secLNG: ddd.mm.sec20m Mag. (m) Heading ()ADDSTOPSTART/R

11、ES.RESETNavigationGPS30NavigationGPSCoordinatesNavigationGPSREMOVE LASTOPEN DESTINATION TABLESpeed (km/h)10GPS System StatusONLINEData SentData ReceivedTimeoutObstacleOPEN COLLECTED DATA TABLECE Projects II Rochester Institute of TechnologySystem Analysis GPS Horizontal accuracy is within 3m of geog

12、raphic location (with WAAS) Minimum refresh rate is 1 sec The speed of the vehicle must be less then 3m/s for most accurate tracking GPS will be configured to transmit geographical location message onlyGPS (Garmin 15L)CE Projects II Rochester Institute of TechnologySystem Analysis Wireless Communica

13、tion Data transferred wirelessly from vehicle to base station via cellular telephone network Motorola E815 cell phone is connected to the MCU via a proprietary serial cable and null modem adapter Data calls are managed with standard serial AT commandsCE Projects II Rochester Institute of TechnologyS

14、ystem Analysis Sensor Concerns Electronic compass is very sensitive to magnetic deviations Optical shaft encoder needs 100% traction for accurate measurement Ultrasonic range finder has wide signal propagation (50) Electronic compass (Devantech CMPS03)Optical shaft encoderUltrasonic range finder (Pa

15、rallax PING)CE Projects II Rochester Institute of TechnologyWhere we stand now Completed tasks Researched and decided on a code development tool (Embedded GNU) Constructed ultrasonic range finder test setup and developed driver code Constructed electronic compass test setup and developed driver code

16、 (I2C) Researched and decided on a wireless communication scheme Constructed optical shaft encoder test setup and developed driver code Improved front wheel steering system on vehicle Developed and tested cellular modem communication schemeCE Projects II Rochester Institute of TechnologyBudgeting Key Components Garmin GPS 15