Transcript - UCF EECS

Autonomous Chasing Robot (ACaR)
an Autonomous Robotic Follower
with License Plate Recognition Capability
Team 19:
Bryan Diaz
Victor Hernandez
Khanh Le
Luis Sosa
BSEE
BSEE
BSEE
BSCpE
Sponsored by___________
Description
ACaR is a cost effective robotic platform with:
• Autonomous Tracking and Following.
• Autonomous License Plate Recognition (ALPR) capability.
• Embedded Operating System.
The ACaR robotic system can potentially be used in law enforcement
and military applications.
Motivations
•
•
•
•
Design a system which potentially could be used in practical
applications.
Interested in Robotic Systems
Acquire Hands on experience in Real Time Computer Vision
Applications
•
•
Real Time Object Tracking
Automated License Plate Recognition (ALPR)
Gain experience in design and integration of electrical systems
•
•
Motor(S)
Power system
ACaR: Specifications
Title
QTY
Units
Size
8 H x 18 L x 12 W
in
Weigh
3~4
kg
Voltage Range Operation
12 – 16.8
V
Battery Life
30+
minutes
Maximum Tracking Target Distance
5
feet
Minimum Tracking Target Distance
2
feet
Maximum Following Speed
Up to 2
km/h
Simultaneous License Plates Detection
Up to 3
plates
High Level Diagram
Single Board Computer
Raspberry Pi 2
Specs:
• 900MHz Quad-Core,
ARM Cortex-A7 CPU
• 1GB RAM
• 4 USB Ports
• Full HDMI port
• Micro SD card slot
• (Added) Heat Sinks and Fan
• (Added) Modified Protective Case
Image Processing
•
OpenCV
•
•
•
CMT algorithm (Consensus-based Matching and
Tracking of Keypoints for Object Tracking)
Cascade Classifier Training (Implements Machine
Learning)
opencv_traincascade (Haar and LBP)
License Plate Recognition (LPR)
Computer Vision
• OpenCV
Open Source
Image Processing
• Leptonica Image
Processing
Library
Open Source
Optical Character
Recognition (OCR)
• Tesseract OCR
Open Source
“Image Usage: Permission Granted under the terms of the GNU Free Documentation License”
LPR Process and Decision
“Permission Granted under the terms of the GNU Free Documentation License”
ALPR Testing Data
Item
Data
Unit
Min. Distance
1
foot
Max. Distance
5
feet
Max. Angle
28
degrees
Max. Simultaneous
6
License plates
Software Block Diagram
Motor Control
•PWM is used to control the speed.
•An H-bridge circuit is used to control
the direction of motor rotation.
•The PWM signal is sent through pins 1
and 2. They are I/O pins of the MCU.
Pololu High Power Motor Driver
• This discrete motor driver bases on the MOSFET H-bridge circuit.
• This board can handle up to 30V of power supply.
• Able to sustain continuous 15A without the heat sink.
• This driver has its own circuit protection if short-circuit or overheat happen.
• The table below shows the different operations of the Pololu Motor Driver.
Specification of Brushed DC Motor
Rated Voltage
Rated Current
Full Speed
Shaft Diameter
Shaft Length
Body Diameter
Total Length
Weight
12V
2.6A
20000 rpm
3mm
10mm
36mm
68mm
161g
Servo Control
•
PPM signal is used to control position
of Servo.
•
PPM uses 1 to 2 ms out of 20ms time
period to encode the information
•
Mechanical steering system limitation:
1.
Between 45 and 135 degree
2.
Turning angle step is 5 degree.
Servo Connections
• The Servo is connected to the MCU directly;
no additional circuit is required for control
• White Wire -> pin 10(P2.2) of Msp430
• Red Wire -> Power supply (5V)
• Black Wire -> Ground pin
http://www.robotshop.com/en/hitec-hs422-servo-motor.html
Micro-controller for DC motor and Servo
•Use MSP430G2553 chip as Micro-controller for motor control.
•MSP430 will communicate with Pi through serial.
• Pi sends instructions to MSP430 via wired serial
communications.
MSP430G2553
http://www.ti.com/ww/en/launchpad/img/launchpad-mspexp430g2-02-thumb.png
MSP430 Connections
Vcc (Pin1)
GND (Pin20)
Reset (Pin16)
RX/P1.1 (Pin3)
P2.1 (Pin9)
P2.5 (Pin13)
P2.2 (Pin 10)
3.3V
Ground
3.3V
TX pin of Rasp Pi
DIR pin of Pololu
PWM pin of Pololu
Servo Motor
Logic Level Shifter
• It is used for interface between MSP430 and
Pololu motor driver.
• It receive 3.3V level signal from MSP430 and
then shifting it up to 5V level before sending signal
to Pololu.
Low Level
High Level
A4
B4
A6
B6
GND
3.3V
5V
Pin9 of Msp430
DIR pin of Pololu
Pin13 of Msp430
PWM pin of Pololu
Ground
Power System
Main DC
Source
Voltage
Regulator
(12 volts)
Motor
Voltage
Regulator
(5 volts)
Raspberry
Pi
Camera
Servo Motor
(Steering)
Voltage
Regulator
(3.3 volts)
MCU
Main DC Source (Rechargeable Battery)
• Main Requirements
• Battery life must be at
least 30 minutes
• Light weight (less
than 1 pound)
• Dimensions
(7x3x2 inches)
• Reasonable price
(less than $50 dollars)
Battery Specifications
Battery Selected
14.8 Volts Lithium
Polymer Ion Battery
Continuous Discharge
42 Amps
Energy Capacity
31.08 watt hour
Battery Life
1 hour
Charge Time
1 hour and 30 minutes
Weight
8.4 oz
Price
$40.66
Voltage Regulators
Features
Linear Voltage Regulator
Switching Voltage
Regulator
Steps up or Steps Down the
voltage, can produce multiple
outputs.
Function
Step down only, output
voltage must be less than
input voltage
Size
Small to medium in portable Small in size, consumes low
design, may be even larger if power
heat sink is needed
Efficiency
Noise
Low to medium
Low
High
Medium to high due to ripple
effect
Output Ripple
Very small almost negligible
Large
Waste Heat
High, when load and voltage
difference is high
Low, most components will
run cool for low power levels
Voltage Regulator (Con’t)
Items
Input Voltage (V)
Current Rating(A)
Motor
12
Up to 6 (A)
Raspberry Pi
5
2 (A)
Servomotor
5
0.5 (A)
Camera
5
0.5(A)
MSP430
3.3
230 (uA)
Webench Tool
RC Car Platform
12V
Reg
Motor
Cam
ProtoBoard
5V
Batt
Reg
3.3V
Reg
Raspberry Pi
Breakout
Board / PCB
1:4 Scale GoKart
•
•
•
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Enough Space for Components
Capable of Speeds of +20 km/h
Low Center of Gravity
Has a Steering System
Has Predetermined Spacing
(e.g. Space set for Battery,
Motor )
Administrative Content
Work Distribution
Section
Bryan
System Definition
Power
Victor
M
M
Computer Vision
S
Electrical System
Protoboard/Integration
Luis
M
Motor Control System
PCB Design
Khanh
M
M
M
S
S
M
Legend
M: Main
S: Support
Budget and Cost
Initial Estimated Budget
Test and Development Cost
Item
Qty
Total Cost
Sensors (various)
Various
$100
PCB MfG/BoM
2
$230
Car Body
2
$100
Car Body
1
$81.00
PCB Fabrication
1
$70
Dev. Boards
1
Misc. Electrical
Various
$150
Misc. Electrical
Misc. Mechanical
Various
$100
IP Camera
1
$110
Tablet
1
$200
Pan/Tilt Mechanism
1
$50
Battery
1
$60
Boeing
$580
$910
TOTAL
$965
TOTAL
Item
Qty
Total Cost
Estimated Production Cost
Item
Qty
Total Cost
Ultra Sonic
1
$4.00
Car Body + Motors
1
$81.00
$145.00
Raspberry Pi
1
$35.00
Various
$446.00
Misc. Electrical
Various
$150.59
Misc. Mechanical
Various
$63.00
USB Camera
1
$50.00
USB Camera
1
Owned
PCB MfG/BoM
1
$115.00
Battery
1
$40.11
TOTAL
$475.50
Issues
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Steering Angle: Limited between 45 to 135 degrees.
Processing time depends on video resolution.
Tracking distance is limited by video resolution.
Voltage Regulator PCB (12 and 5V) not functioning.
Ultrasonic sensors acquired proved to be inaccurate.
Inertia Measuring Unit (IMU) malfunctioning.
Q&A Session