Transcript GPS Robot Navigation Critical Design Review

GPS Robot Navigation
Critical Design Review
Chris Foley, Kris Horn, Richard Neil
Pittman, Michael Willis
Need
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Unmanned and automated systems
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Military
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Can protect human lives
Can provide convenience and safety
Warfare
Dangerous locations
Surveillance
Civilian
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Everyday navigation
Goal and Objectives
Goal: Develop a GPS guided system
that will successfully navigate to a
series of pre-defined coordinates.
 Objectives:
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Stable, sturdy system
 Able to start at any location
 Follow a pre-defined path
 Be able to avoid obstacles
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Litterature
www.oopic.com
 www.junun.org/MarkIII
 The Devantech SRF04 Ultrasonic
Range Finder
 Optical EC Encoder Kit
Documentation
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Design Contraints
Budget
 Time
 Technical Scope
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Alternative Solutions
Compass or not ?
 Reprogram using a laptop, or a
keypad ?
 Control the car by tapping into the
servos or by using the remote control
circuit ?
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Final Design Breakdown
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Mark III Board with
OOPic provides
control
Sonar Configuration
provides obstacle
detection
GPS and Compass
provide navigation
information
Final Design Breakdown
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User interface
through serial
connection to
computer
LCD provides user
feedback
Battery and voltage
regulation provide
power to components
Subsystems
Object Detection System
 Velocity Control System
 Navigation System
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Object Detection
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Sonar:
-- Efficient outdoors
-- Far range
Devantech SRF04
Ultrasonic range
finder.
Range 3” – 10’
SRF04 Controller Interface
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4 pins: Power,
Ground, input
Trigger, and output
Echo.
Trigger 0→1: Sonar
emits a ping and
the Echo → 1.
Echo → 0 ping
returned.
SRF04 Algorithm
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Time length Echo is
high.
Sea level sound
travels 2’/1.8 mSec.
Obj. Distance ft. =
(time sec.) *
(1/.0018)
Sonar Configuration
Velocity Control
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Manual speed
control
Servo controls
motor voltage.
Optical Encoder
measure angular
velocity.
Optical Encoder
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E3 optical encoder
US Digital Corp.
3 output channels
A, B, and Index
used read
quadrature track.
A leads B, rotating
CW. B leads A,
rotating CCW.
Index: 1 pulse / rev.
Velocity Control (cont.)
Navigation System
Inputs: destination coordinates,
current GPS coordinates, compass
heading, steering commands (from
collision avoidance system)
 Outputs: steering control commands,
speed control commands, coordinate
reading
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Navigation System
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Function: control the movement of the
robot along a path
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Uses algorithm programmed into the
OOPic to make path calculations
based on current inputs
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Will always choose best path from
current location
Validation and Testing
Procedures
Test individual components
(speed control, steering, sonar, lcd,
gps, compass, navigation algorithm)
 Integrate and test piece by piece
 Test system as a whole
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Schedule
Division of Labor and
Responsibilities
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The GPS unit and Navigation
Algorithm: Chris and Michael
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Compass, Sonar and Servos:
Kris and Neil
Economic Analysis
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Economical Viability
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Sustainability
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Total cost per unit: $352.50
Components from various vendors
Manufacturability
FCC compliant GPS
 Production yield dependant on
number of workers
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Societal, Safety, and
Environmental Analysis
Use the robot for locations that are
unsafe for humans or difficult to get to.
 Exhibit normal care and safety
measures that apply when using
electronic equipment
 Carefully plan path so as not to harm
environment
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