Bull·E: The Recycling Robot SECON Team B Final Presentation December 2, 2008

Team B Dr. Bryan Jones, Advisor Jeff Brantley Jonathan Bryant Brooke Grantham Kevin Vu SortingXX StorageXX DiscriminationXX NavigationXX

Outline Competition Overview Project Division Design Overview Practical Constraints Technical Constraints System Testing Spring Semester Goals

Problem Statement Autonomous recycling robot for 2009 IEEE SECON hardware competition Must locate, acquire, sort, and store recyclables on the robot. 10 Recyclables include: –5 aluminum cans –3 plastic bottles –2 glass bottles Maximum Starting Size: 12”x12”x18” [1] [2]

Competition Playing Field Artificial turf 8’x8’ Electric dog fence boundary 10’x10’ Hard boundary Recyclables will be placed on their sides The recyclables arrangement will be the same for each heat [1]

Competition Recyclables [1]

Outline Competition Overview Project Division Design Overview Practical Constraints Technical Constraints System Testing Spring Semester Goals

Team Tasks Driving Navigation Boundary Detection Acquisition Target Detection Discrimination Sorting Storage Team A Team B

Outline Competition Overview Project Division Design Overview Practical Constraints Technical Constraints System Testing Spring Semester Goals

Physical Model

Informational Model

Prototype

Outline Competition Overview Project Division Design Overview Practical Constraints Technical Constraints System Testing Spring Semester Goals

Practical Constraints NameDescription Manufacturability The robot must fit inside a 12" X 12" X 18" box before beginning of each round. Sustainability The robot must operate at least 4 minutes on a single battery charge.

Manufacturability Actual dimensions: 19”W x 16”H x 15”D –Inaccuracies to be expected in prototype Standard-length Vex Robotics parts for frame exaggerate height Breadboard and wires add inches to depth –Final design will require minor adjustments, not a major redesign Use custom-size materials Move servos & motors into dead storage space

Practical Constraints NameDescription Manufacturability The robot must fit inside a 12" X 12" X 18" box before beginning of each round. Sustainability The robot must operate at least 4 minutes on a single battery charge.

Sustainability Robot must be able to run for a full round (4 min.) on a single battery charge Battery choice: –Lithium-Ion Powerizer (14.8 V, 4800 mAH) High energy density Protection circuitry housed on battery package Battery life: –Theoretically, 4.8 hours –Realistically, about 15 minutes (older battery)

Outline Competition Overview Project Division Design Overview Practical Constraints Technical Constraints System Testing Spring Semester Goals

Technical Constraints NameDescription Target Discrimination The robot must recognize the containers as being either glass, aluminum, or plastic. Sorting The robot must sort the recyclables into three different containers. Storage Capacity The robot’s storage compartments must accommodate all 10 containers that will reside on the playing field. Navigation The robot must travel within the 10’ X 10' square boundary without contacting or extending over the boundary.

Target Discrimination IR Sensor and FSR –IR senses object presence and signals robot to begin sampling FSR output –FSR outputs voltage based on weight of recyclable

Lift IR Sensor Testing ExpectedActual No Item0.5V0.6V GlassV out > 0.75V1.42V PlasticV out > 0.75V1.23V AluminumV out > 0.75V1.72V

FSR Testing Expected1234 Glass3.0V3.21V3.51V3.54V3.56V Plastic0.6–2.0V1.41V1.44V1.38V1.32V Aluminum0.0V

Target Discrimination Problems –IR sometimes gave false detection Noise on sensor output –FSR placement Glass bottles and aluminum cans were identified incorrectly Proper weight distribution onto sensing area of multiple FSRs

Target Discrimination RecyclableExpected12345 GlassGreen Red 0.0VYellow 1.86V PlasticYellow AluminumRedYellow 0.86V Red

Target Discrimination Solution –Filter IR sensor output with capacitor –Adding layer on FSR to center weight onto sensing area –Using only one FSR in the middle –Adding brackets to the sides of the lift

Target Discrimination

Technical Constraints NameDescription Target Discrimination The robot must recognize the containers as being either glass, aluminum, or plastic. Sorting The robot must sort the recyclables into three different containers. Storage Capacity The robot’s storage compartments must accommodate all 10 containers that will reside on the playing field. Navigation The robot must travel within the 10’ X 10' square boundary without contacting or extending over the boundary.

Sorting Lift System –Rear Placement –Stepper motor –Guide Rails –Trap Door Servo

Sorting Problem –Binding when lifting glass bottle Short Term Solution –Decreasing the speed to increase the torque capability Long Term Solution –Restructure the bracing of lift platform so weight of container is distributed evenly

Stepper Motor Testing Verify correct output stepping sequence Q1Q2Q3Q4 Step Step Step Step Step 11010

Stepper Motor Testing Oscilloscope readings show correct stepping sequence Signal captured starts with step four

Stepper Motor Testing Two different delay periods used –increases force needed for lifting glass bottle weight Measurements shown include the period for two steps

Storage Box Servos Measured PCM signals from PIC Visually inspected servo positions Trap door closed / Flap openTrap door open / Flap open

Technical Constraints NameDescription Target Discrimination The robot must recognize the containers as being either glass, aluminum, or plastic. Sorting The robot must sort the recyclables into three different containers. Storage Capacity The robot’s storage compartments must accommodate all 10 containers that will reside on the playing field. Navigation The robot must travel within the 10’ X 10' square boundary without contacting or extending over the boundary.

Storage Capacity Storage Box –3 internal compartments –Plastic bottle compartment Expanded to store bottles –Aluminum can compartment Trap door

Storage Capacity

Technical Constraints NameDescription Target Discrimination The robot must recognize the containers as being either glass, aluminum, or plastic. Sorting The robot must sort the recyclables into three different containers. Storage Capacity The robot’s storage compartments must accommodate all 10 containers that will reside on the playing field. Navigation The robot must travel within the 10’ X 10’ square boundary without contacting or extending over the boundary.

Navigation Navigation not yet implemented –Integration of both teams’ subsystems took longer than expected –Dog fence sensor unavailable for boundary detection –Will be a major focus in the spring

Outline Competition Overview Project Division Design Overview Practical Constraints Technical Constraints System Testing Spring Semester Goals

System Test StepComponent Container DetectionLift IR Container DiscriminationFSR SortLift and Box Servos StorageBox Compartments

System Test Results Step ContainerDetectionDiscriminationSortStorage Aluminum Can Pass Plastic Bottle Pass Fail Glass Bottle Pass

Outline Competition Overview Project Division Design Overview Practical Constraints Technical Constraints System Testing Spring Semester Goals

Rebuild storage box –Rigid material to stabilize robot frame –Resize to house motors & fit all cans Fine-tune discrimination Brace & speed up stepper motor Implement & test navigation PCB Design

References [1] Institute of Electrical and Electronics Engineers. Southeastcon 2009 Hardware Competition: The Recycling Robot, 2008 August 28, Con-2009-Hardware-Rules.pdf. Accessed September 16, [2] J. Brantley, J. Bryant, K. Grantham, K. Vu. Bull-e: An Autonomous Recycling Robot, n/FinalDesignDocumentTeamB.pdf. Accessed December 1, 2008

Questions?