Transcript Mars Rover

Mars Rover
By:
Colin Shea
Dan Dunn
Eric Spiller
Advisors: Dr. Huggins, Dr. Malinowski
Outline
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Project Summary
Review of Previous Work
Division of Labor
Project Description
Data Sheet
Equipment and Parts
Design Changes
Schedule
Progress Update
Results
Future Revisions
Project Summary
• The main objective is to design the Rover for long battery life
that must last 7 days without recharging.
• The Rover will use a PC104 computer to control the interface
between the user and the Rover.
• It will also use the MicroPac 535 microprocessor to control
low level software such as the motors, the sonar system, and
the battery level.
• The user will be able to enter a specific distance, move the
Rover using the keypad, or rotate the Rover to get a preferred
direction.
Previous Work
• 2002
• Rob Shockency and Randall Satterthwaite
• Robotic Platform Design
• EMAC 8051 and a CPLD
• Design Goals
•
1. Create Cheaper version of Telerobotics 2001
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2. Upgradeable and expandable in the future
Division of Labor
Dan Dunn
Assembly Code
- Motor Control
- Wheel Sensors
- Battery Charge Level
- Serial Communication
- Acoustic Sensors
Colin Shea
Java/Server
- Image Capture
- Rover Controls
- Serial Communication
Eric Spiller
Hardware
- DC Motors
- Platform Construction
- H-bridge/Motor Driver
- Battery Charger
Functional Description
User
Charge
Full Charge
Low Battery
Timeout
Wait
Manual
Disconnect
Connect
Sleep
Low Battery
Activity
Low Battery
Low Battery
Functional Description
• Wait mode –
• All systems are powered, except the motors.
• The CPU monitors the wireless card for network activity
• The last image captured from the camera is displayed to the
user.
• Web page accessible to user
• Battery Status is monitored
• Sleep mode –
• The sub-systems are powered down except for the CPU and
the wireless network card.
• CPU runs in a reduced power mode.
• Web page accessible
• Battery Status is monitored.
• Rover remains in sleep mode until signaled by the user.
Functional Description
• Low battery mode –
• Battery drops below 10% of charge Distance and Direction
Control
• Email sent to Dr. Malinowski requesting a charge
• Rover shuts down all components, except Micropac 535.
• User mode –
• All Systems powered
• Distance and Direction Control
• Web Page accessible to user
• Image capture and display
• Charge mode –
• Rover continues to charge until power button is pressed
• Stays in this mode until battery level reaches 100%
Functional Description
User
Charge
Full Charge
Low Battery
Timeout
Wait
Manual
Disconnect
Connect
Sleep
Low Battery
Activity
Low Battery
Low Battery
System Block Diagram
Java Applet
Internet
Control TCP/IP
USB Protocol
Camera
Commands
Status
PC104
Upper level software
Battery Charge
Level
ge
lta
Vo
MicroPac 535
Embedded System
H-Bridge
l
na
Sig
TTL
Acoustic
Sensors
l
Transmit pulse
Wheel Sensors
Sign
a
Echo pulse
Motor
M
PW
Bit Stream
User
Computer
Wireless
Network
card
digital bit stream
802.11b
RF signal
Image
Object
Software Flow Chart
• High Level Software
• Rover Control
Software Flow Chart
• High Level Software
• Image Retrieval/Display
Software Flow Chart
• Low Level Software
• Motor Control
Software Flow Chart
• Low Level Software
• Object Detection
Software Flow Chart
• Low Level Software
• Battery Voltage Level
Micropac 535
Battery terminal
voltage
Compare to Data
Table
A/D converter
Us
ot
s
p re w
lo
Charge too low
a rg
e
Display to user
approximate battery
charge level
Charge Good
Continue operating
rover
User not present, charge good
Stop rover and switch
to low charge mode
n
er
ch
User present
t,
en
Data Sheet
Specifications
Turning accuracy - ± 5° for an individual turn command
Turning resolution - 15°
Driving accuracy - ± 5cm and ± 2° for a 100cm command
Camera capture speed – 5 frames/sec @ 324x288 resolution for a
10BaseT connection
Weight – ~33lbs
Battery life – 7 days without a recharge
Top speed – 10cm/s
Battery charge level accuracy - ± 5%
Acoustic sensors –
Time between transmit signals – 1 second
Farthest object detection – 200cm
Closest object detection – 5cm
Data Sheet
PC104 –
Max Current, during boot – 1.5A
Normal operating current – .8A
Sleep mode current – .026A
Processor – National Semiconductor Geode Processor @ 300MHz
RAM – 128MB
Video – Onboard Video card
PCMCIA module –
Current - .07A
Wireless Card –
Linksys WPC11
Max Current - .3A
Current in Sleep mode - .02A
Hard Drive –
IBM Travelstar 2.5 inch IDE hard drive, 10GB
Max Current - .94A (Spin-up Current)
Current in Sleep Mode - .02A
Camera –
Logitech USB Webcam
Max Current - .1A
Motors –
Model number – GM9236
Gearing – 1:65.5
Voltage – 12V
Power Calculations
Power Consumption for Sleep Mode:
PC104 computer
PC104 PCMCIA module
IDE Laptop Hard drive
PCMCIA Wireless Card
EMAC
Total
.026A
.07A
.015A
.009A
.045A
+ _____
.165A
24hrs * 7days = 168hrs
168hrs * .165A = 27.72 Ah @ 5V
27.72Ah * 5V = 138.6Wh
Using 3 - 12 Volt, 7.2Ah batteries:
12V * 7.2Ah * 3 = 259.2 Wh available
Power Calculations
Power Consumption for User Mode:
PC104 computer
PC104 PCMCIA module
IDE Laptop Hard drive
PCMCIA Wireless Card
EMAC
Camera
2 DevanTech SRF04
Total
.800A
.070A
.400A
.285A
.045A
.100A
.060A
+ ______
1.760A
Power Calculations
• Motors with a load draw 0.5 - 0.8 A.
• Total Amps with motors: 1.76A + (0.4A * 2) = 2.56A
• [(0.8A * 12V + 1.76A * 5V) * 4.1% + (.165A * 5V) * 95.9%] * 168hrs =
259.2Wh
• If the Rover is in User Mode for 4.1%, then
168 hrs * 4.1% = 6.88hrs of battery life dedicated to User Mode
Parts and Price List
Part
Manufacturer
Price
10 Gb
IBM
$80.00
128 Mb RAM
Infineon
$14.20
PC/MCIA Wireless Card
Logictech
$69.00
USB Webcam
Logictech
$16.00
PC104 300MHz w/ USB
National Semi
$399.00
Dual PC/MCIA Adapter
National Semi
$94.00
Pittman DC Motor #9236
Pittman
Total
$672.20
Design Changes
• Replaced Linux based operating system
with Windows based operating system
• Video Card was incompatible with Linux although manufacturer
stated the card was compatible
• Linux operating system was not stable on PC-104 board
Design Changes
• Flash Memory Card and PCMCIA Hard
drive replaced by Laptop Hard drive
• Flash Memory Card was not capable of booting the PC-104 at
start-up
• PCMCIA Hard drive was not visible by computer until system
completed start-up sequence
• Laptop Hard drive booted easier and still remained low power
• Flash Memory Card was used as secondary drive to limit usage
of Laptop Hard drive
• Contained component software for Web Server (Apache and Java)
Schedule
Time Frame
Accomplishment
1/19/03 – 2/8/03
Operating System
2/9/03 – 2/22/03
Serial Comm, H-Bridge, Camera
2/23/03 – 3/1/03
PWM, Java Program, Wheel Sensor
Program
3/2/03 – 3/8/03
Movement Routines, Command
Coding
3/9/03 – 3/15/03
User Interface
3/23/03 – 4/12/03
Tested Mobility
4/13/03 – 4/22/03
Acoustic Sensors, Battery Voltage
Testing
Progress Flow Chart
Java Applet
digital bit stream
User
Computer
Wireless
Network
card
802.11b
RF signal
Image
Internet
Control TCP/IP
PC104
Upper level software
Status
USB Protocol
Camera
Commands
Green = Developed
Battery Charge
Level
g
lta
Vo
e
H-Bridge
n
Sig
al
Acoustic
Sensors
l
Transmit pulse
Wheel Sensors
TTL
Sig
na
Echo pulse
Motor
M
PW
Bit Stream
MicroPac 535
Embedded System
Object
Results
• H-bridges introduced noise to the system
Future Revisions
• Replace H-Bridge with Power Amp / Switching
Circuit
Mars Rover
Mars Rover
Questions and Answers