1. Chase Davis Daniel Phifer Nimesh Patel ReNina Fields Larry Lybrook Rachael Green Matthew Wright Eric Kneynsberg Jimmy Simmons University of Alabama Department of Electrical and Computer Engineering 1

2.  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

3.  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

4.  Three space stations ◦ Skylab ◦ Mir ◦ International Space Station  Mir collision  Automated Transfer Vehicle (ATV)  May 8th, 2007 Autonomous Space Transport Robotic Operations (ASTRO) 4

5.  3-Dimensional problem ◦ Orbital rendezvous and docking ◦ 6 degrees of freedom  2-Dimensional problem ◦ Capstone Fall 2007 ◦ 3 degrees of freedom 5

6.  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 6

7.  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 7

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9.  Three modules: Chase Vehicle Computer Target  Five sub-systems ◦ Platform ◦ Wireless communication ◦ Image processing ◦ Navigation ◦ Control console 9

10.  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 10

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12.  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 12 Y-axis view X-axis view

13.  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 docking Group Members: Eric Kneynsberg, Larry Lybrook, Nimesh Patel, Daniel Phifer 13

14.  Chase  Target 14 ComponentCurrent (mA) Microcontroller100* Wireless100* Compass15 Long Range IR Sensor 50 Short Range IR Sensor 50 Servos1500* Camera200* TOTAL2015 mA ComponentCurrent (mA) Microcontroller100* Wireless100* Compass15 TOTAL215 mA * Measured in Lab

15.  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 15

16.  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 16

17.  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 17

18. 18  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

19. 19  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

20.  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 20

21. 21  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

22.  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 22

23.  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 23

24.  Matlab ◦ Powerful math and graphical functions which allows for future upgrades ◦ Slower processing is not detrimental ◦ Reduced learning curve 24

25.  MatLab simulation program  Mimic movement of vehicle  Include code to manipulate vehicle Group Members: Chase Davis, Jimmy Simmons, Eric Kneynsberg, Larry Lybrook 25

26.  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 26

27.  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 27

28.  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 28

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32.  Control system failure  Collision with people or other objects  Possible hazardous materials in system components  Possible hazardous payloads 32

33.  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 33

34.  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 34

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