Autonomous Rendezvous System Capstone Design Proposal
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Transcript of Autonomous Rendezvous System Capstone Design Proposal
Autonomous Rendezvous SystemCapstone Design Proposal
Chase DavisDaniel PhiferNimesh PatelReNina FieldsLarry Lybrook
Rachael GreenMatthew WrightEric KneynsbergJimmy Simmons
University of Alabama Department of Electrical and Computer Engineering1
Problem statement Background
information Possible overall
solutions Plan of action Detailed specifications
◦ Platform◦ Wireless communication◦ Image processing◦ Navigation◦ Control console
Documentation Validation plan General schedule and
budget Safety and
environmental impact
2
Presentation Agenda
Chase vehicle is to rendezvous with target given starting requirements:◦ The x and y position for
the chase vehicle is x = sqrt(9-y^2)
◦ The angle of incidence, Ɵ, is such that -tol < Ɵ < tol The tolerance will be
determined once the infrared sensors have been tested
◦ The yaw is equal to Ɵ (front of vehicle pointing at target)
Rendezvous is considered successful when:◦ ∆X = 2 inches◦ ∆Y = ± 2.00 inches◦ ∆Yaw = ± 8.00 degrees
3
Problem Statement
Three space stations◦ Skylab◦ Mir◦ International Space Station
Mir collision Automated Transfer Vehicle
(ATV) May 8th , 2007 Autonomous
Space Transport Robotic Operations (ASTRO)
Background
4
3-Dimensional problem◦ Orbital rendezvous and
docking◦ 6 degrees of freedom
2-Dimensional problem◦ Capstone Fall 2007◦ 3 degrees of freedom
Background
5
Triangulation ▣◦ Received/transmit signal strength of wireless modules◦ Very high precision and accuracy
Camera only◦ Enables a high degree of precision◦ Computationally expensive
IR sensors and compass only◦ Cheap◦ Easy to configure◦ Not accurate enough for the precise mechanics involved
in docking
Possible Overall Solutions
6
IR sensors, compass and a camera Phase 1 ▣
◦ IR sensors and compass provide a coarse but fast way of zeroing Y and Yaw
◦ Move chase vehicle 2 feet out from stationary target (2,0,0)
Phase 2◦ Camera provides the needed precision to approach the
target carefully, slowly, and with enough accuracy to rendezvous/zero X
◦ Chase vehicle slowly approaches stationary target from its position 2 feet away
Overall System
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System Overview
8
Target
Computer
Chase Vehicle
Microcontroller
Compass
Camera
IR Sensors
`
Microcontroller
Compass
Three modules:
Chase Vehicle Computer Target Five sub-systems
◦ Platform◦ Wireless communication◦ Image processing◦ Navigation◦ Control console
Plan of Action
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Develop each sub-system completely independent of other sub-systems
Integrate each sub-system into the overall system◦ Modify the sub-system to ensure proper interaction with
the other sub-systems and module Test, validate, and refine the system
◦ Validate the performance of each sub-system◦ Validate the proper interaction between sub-systems◦ Validate the overall system performance
Plan of Action
10
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Sub-system Communication
Image Processing
Control Console
Navigation
Wireless Communication
Platform
Camera image processing commands
Target image information
Movement commands
Chase vehicle position
Chase vehicle command
Chase vehicle
command
Chase vehicle position
RS-232
TTL UART
PWM
Chase◦ TK1 Basic Kit◦ Palm Pilot Robot Kit (PPRK)◦ Octabot
Wheel position◦ Scooterbot II
Wheeled Servo driven Two 7” diameter decks Cost $59.95
Target◦ Façade◦ Possibility of docking
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Platform Possibilities
Y-axis view X-axis view
Chase◦ Testing done using microcontroller pulse width modulation
(PWM)◦ Movement
• Clockwise• Counter clockwise• Forward• Reverse
◦ Speed• Five different speeds
◦ Effects of overall equipment weight Target
◦ Contingent on dockingGroup Members: Eric Kneynsberg, Larry Lybrook, Nimesh Patel,
Daniel Phifer
Platform Testing Plan
13
Chase Target
14
Power Budget
Component Current (mA)
Microcontroller 100*
Wireless 100*
Compass 15
Long Range IR Sensor
50
Short Range IR Sensor
50
Servos 1500*
Camera 200*
TOTAL 2015 mA
Component Current (mA)
Microcontroller 100*
Wireless 100*
Compass 15
TOTAL 215 mA
* Measured in Lab
XBee-PRO Starter Kit◦ 60 mW output power◦ 1-mile range◦ RS-232 & USB development
boards◦ 2 OEM RF modules◦ Cost $179.00
XBee Starter Kit◦ 1 mW output power◦ 100 ft. indoor range◦ RS-232 & USB development
boards◦ 2 OEM RF modules◦ Cost $129.00
Since 3 modules and development boards are needed, and the XBee Starter Kit only provided 2 of each, 1 more module and board will be purchased
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Wireless Kit Possibilities
Performance◦ Power output: 1mW◦ Indoor range: Up to 100 ft
Baudrate◦ Interface baudrate: 115,200 ◦ Operating frequency: 2.4 GHz
Networking◦ Networking topology: peer-to-peer, point-to-point &
point-to-multipoint Error handling
◦ Retries and acknowledgements
XBee Starter KitDetailed Specifications
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Simultaneously send data from control console and target to chase vehicle
Send data from chase vehicle to target and control console
Look for a proper transition on chase vehicle between control console channel and target channel
Group Members: Rachael Green, Daniel Phifer, ReNina Fields
Wireless Testing Plan
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Terasic TRDB_DC2◦ Not useable with
microcontroller CMUCam1 - $109
◦ Low resolution CMUCam3 - $239
◦ High price, unneeded functionality
CMUCam2 - $179◦ Compromise in price and
image resolution◦ Available for immediate
testing
Image Processing Possibilities
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Test for most effective beacon◦ Contrasting printed image◦ LEDs
Test color tracking function◦ Distance from beacons◦ Angle of incidence◦ Camera/beacons in motion
Test distance measurement◦ Assume 90° incident angle◦ Resolution◦ Repeatability
Group Members: Matt Wright, Jimmy Simmons, Rachael Green, Nimesh Patel
Image Processing Testing Plan
Camera – CMU Cam 2 IR sensors
◦ Infrared “ranger” sensors will help find the target◦ Operating supply voltage of 4.5 to 5.5 Volts◦ Long range IR - Sharp GP2Y0A02YK $12.50
8” to 60” range◦ Short range IR – Sharp GP2D120 $12.50
1.5” to 12” range Compass
◦ Devantech R117 $52.00◦ Dinsmore compass $14.00
Optical sensors◦ Still researching ~$1.08
Navigation
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Navigation Possibilities Altera Cyclone II FPGA
Starter Development Kit◦ Computation power◦ Learning curve◦ Price $150.00
Adapt9S12E128 Basic Module with 112-pin MCU◦ Equipment and language
familiarity◦ Size◦ Price $83.00◦ Limited memory
IR sensors◦ Test and validate ranges and detection surfaces
Compass◦ Compare readings from compass against an analog
compass to test accuracy and precision
Group Members: Eric Kneynsberg, Matt Wright, Jimmy Simmons, ReNina Fields, Chase Davis
Navigation Testing Plan
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C#◦ Better visuals◦ More elegant and
efficient design◦ Stand-alone program◦ Need .NET Framework
LabView◦ Very fast data acquisition
(DAQ)◦ Numerous powerful
functions◦ Learning curve◦ Expensive DAQ modules◦ Not stand-alone
MatLab◦ Excellent math and
graphing capabilities◦ Image processing
toolboxes◦ Slower processing◦ Not stand-alone
Control Console Possibilities
23
Matlab ◦ Powerful math and
graphical functions which allows for future upgrades
◦ Slower processing is not detrimental
◦ Reduced learning curve
Control Console Solution
24
MatLab simulation program Mimic movement of vehicle Include code to manipulate vehicle
Group Members: Chase Davis, Jimmy Simmons, Eric Kneynsberg, Larry Lybrook
25
Control Console Testing Plan
The group will provide the user with:◦ User Manual◦ System Specification Document updated weekly
Each sub-system will be independently documented
Documentation responsibilities will be shared by all team members
The group guarantees to deliver a prototype rendezvous system suitable for use as a demonstration during departmental recruiting activities by December 2007
Documentation
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Validate each sub-system before integration◦ Check for desired behavior, performance, stability
Validate each sub-system after integration◦ Check for proper interactions with other sub-systems,
stability, performance Validate the system
◦ Check for completion of objective
Validation Plan
27
Ad-hoc method of validation◦ Small scale◦ No plans for mass production◦ Limited access to specialized testing equipment◦ Limited time to implement and refine a systematic
validation procedure Acceptance will be defined by client’s acceptance
standards and the equipment’s rated tolerances
Validation Plan
28
Compasses, $106.65
Short Range IR Sensors, $27.65
Long Range IR Sensors, $27.65
Wireless Modules, $38.00
Wireless Board, $60.00
Microcontrollers$199.91
CMUCam2, $179.00
Batteries (4500 mAh),
$70.00
Batteries (2300mAh),
$28.00
Platform, $80.00
Optical Sensors, $10.80
Misc ICs and Regulators,
$20.00
Unused, $152.34
Estimated Budget
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Compasses,$106.65
Short Range IR Sensors, $27.65
Long Range IR Sensors, $27.65
Wireless Modules, $38.00
Wireless Board, $60.00
Microcontrollers$199.91
Unused, $540.14
Current Budget
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Schedule
31
Control system failure Collision with people
or other objects Possible hazardous
materials in system components
Possible hazardous payloads
Safety Problems
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Long range operation uses long range IR sensors◦ Line up yaw and Y axis from long range
Short range operation uses short range IR sensors and color camera◦ Stop movement if IR sensor and camera data don’t
match or are out of expected ranges◦ Variable speed based upon distance from target
Collision Avoidance
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Simulation of 3D rendezvous problem through 2D problem solving
Breakdown problem into sub-systems◦ Platform◦ Wireless communication◦ Image processing◦ Navigation◦ Control console
Safety concerns◦ Collision avoidance
Overall deliverable◦ Working prototype that can rendezvous autonomously
with a target within system specifications
Conclusion
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Questions?
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