Milestone #3 Design Review Group 4 Victoria Jefferson Reece Spencer Andy Jeanthanor Yanira Torres Kevin Miles Tadamitsu Byrne 1

Preliminary Rules released!!! Theme: RoboLove New addition Torpedo Launcher Similar Tasks Validation gate Orange Path Marker Dropper PVC Recovery Acoustic Pinger Same weight and size constraints as previous years Must weigh under 110 pounds Six-foot long, by three-foot wide, by three-foot high 2

Conceptual Design 3

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5 Overview Major Components Motors/ Thrusters PropellersBatteries Inertial guidance Sensors Microco ntroller Grabber/ Dropper FrameHull

Motors/Thrusters CostThrustPower Consumption Dry Weight Rank Weighting Factor N/A SeaBotix BTD Crust Crawler 400HFS Technadyne

Motors/Thrusters SeaBotix SBT150: Chosen for functional ability and water resistance as well it’s built- in motor controller, voltage regulator, and low power consumption Four thrusters will be placed on the AUV in a configuration that will allow for forward/reverse powertrain, left/right turning and depth control Similar to BTD150 but includes motor controller 7

Motors/Thrusters Motor Controller: Built-in voltage regulators Automatic shut-off if it receives less than 20V DC and more than 30.1 V DC Wiring configuration calls for 14- gauge power wire as well as Data and Clock inputs that utilize 18- gauge wire Power Consumption/ Placement: Max Amp.: 5.8A(30 sec duration) Max Cont. Amp.: 4.25A Max Power: 150W(each motor) Thrusters located on left/right for turning and bottom/front for balance and weight distribution 8

Risks Associated with… The Motors/Thrusters Failure of one or more thrusters Motorcontroller malfunction Orientation of thrusters does not provide full range of motion 9

Batteries Thruster Battery Options High Polymer Lithium Ion Battery: Max voltage of 14.8V Max capacity of 20AH Max current of 30A Will allow AUV to run for 1 hour at maximum amp draw Lithium-Iron Phosphate Battery: More expensive than high polymer lithium ion Slightly heavier than the high polymer lithium ion No justified gain for the price Nickel Battery: Nickel Metal Hydride batteries could not supply sufficient amp hours Nickel Metal Cadmium batteries do supply sufficient amp hours or voltage and are very heavy 10

Vehicle Power System Batteries Two 14.8 V DC batteries in series Built-in PCM maintains a voltage between 20.8 V and 33.6 V PCM prevents a drain of anything greater than 40A Charge time = 10.1 hours 30 min wait time is required after charge to allow PCB to evenly distribute cells in the battery 11

Batteries Components: Hercules Switching Regulator Up to 40V input Outputs 5V, 6A Used for “USB” power for onboard components Switching allows for over %70 efficiency All components connected with inline fuse rated at peak amperage consumption 12

Risks Associated with… 13 The Batteries Battery over discharging Battery overcharging Shorting terminal Battery failure Battery not powerful enough to power AUV

Hydrophones SensorTec SQ26-01 hydrophone Full audio-band signal detection and underwater mobile recording Operates at required sound level (187 decibels) Performs in required range of the pinger (20-30 kHz) Chosen over Reson TC4013 because it is more cost-efficient and provides the functionality we need 14

Hydrophone Configuration 4 hydrophones will be utilized to determine the location of the pinger 2 hydrophones will be placed horizontally to determine direction The other two will be vertical in order to determine the depth 15

Risks Associated with… 16 The Hydrophones Failure of one or more hydrophones Damaged Malfunctioning Hydrophones not compatible with microcontroller

Inertial Measurement Unit (IMU) Navigation/Stability Control PhidgetSpatial 3/3/3-9 Axis IMU Accelerometer: measure static and dynamic acceleration (5g) Compass: measures magnetic field (±4 Gauss) Gyroscope: Measures angular rotation (400°/sec) Chosen for low cost and because it contained a compass instead of magnetometer unlike other IMUs 17

Risks Associated with… 18 The IMU Magnetic interference-Compass “Drift”- Gyroscope IMU damaged IMU malfunction

Camera Housing Analysis 19 Stress Tensor (Pa) Total Deflection (in) PVC piping Viewing lens Aluminum Plate

Risks Associated with… 20 The Camera Housing Leaks as a result of: Fracture Improper sealing

Cameras Cameras chosen: 3 Unibrain Fire I CCD webcams Originally chose a Dynex webcam as well Needed for light/color and shape recognition CCD camera chosen for ability to operate in low light conditions The cameras chosen for cost efficiency as well as compatibility with our software 21

Cameras Positioning Forward facing CCD camera for floating objects Downward facing CCD camera for objects on the pool floor Overhead camera for shape recognition Housed in watertight casing to protect from water damage 22

Risks Associated with… 23 The Cameras Failure of one or more cameras Damaged Malfunctioning Camera not compatible with microcontroller Camera power failure

Software for Sensors Hydrophones In the process of finding a Linux software capable of processing and managing data IMU RS-232 interface Visualization and Configuration Software: SmartIMU Sensor Evaluation Software Linux C Source Code Cameras Digital Image Processing using MatLab 24

Microcontroller The BeagleBoard: Main Computer OMAP 3530 Platform USB/DC Powered 2GB NAND Memory 1GB MDDR SDRAM Additional memory can be added (if necessary) A 6 in 1 SD/MMC connector is provided as a means for expansion UART 25

Microcontroller Software: Operating system will be a Linux distribution Ubuntu, Angstrom and Debian-GNU are the current choices Mission code will be written in a combination of C/C++ Program will receive data from sensors as input Output will be sent via PWMs to the motor controllers to drive the motors Program will be decision based using mostly if-else statements and loops 26

Risks Associated with… 27 The Microcontroller and Software Microcontroller power failure Error in sensor-microcontroller communication Purchased sensors not compatible with microcontroller Microcontroller does not have all the necessary inputs/outputs to communicate with the sensors Software not executing tasks properly Errors in program

Mechanical Grabber Used to complete the final task of the mission Grasp and release mechanism located at the bottom of the AUV Our design will depend on the size and orientation of the rescue object The current design is to have a mechanical claw attached to a solenoid that will attach to an object in the water 28

Risks Associated with… 29 The Mechanical Grabber Mechanical grabber malfunction Mechanical grabber damage

Marker Dropper Use to complete tasks in which a marker must be dropped Will be machined out of aluminum Utilize waterproof servomotor that will rotate marker dropper mechanism to release markers Traxxas servomotors will be used This method was chosen because it was the most cost efficient 30

Risks Associated with… 31 The Marker Dropper Marker dropper malfunction Marker dropper damage Marker dropper power failure

Frame Overview Simplistic Design constructed of 80/20 Aluminum Allows for easy adjustability 80/20 is structurally sound and can support all components of the AUV The design mitigates vibration and will reduce hydrophone interference Hull will be placed within the frame 32

Hull Overview Hull consists of a watertight Pelican Box Purchasing Pelican Box is simpler than designing watertight housing and is also inexpensive Hull will house all onboard electronics Reduces the risk of water damage to electronics Exterior components will be connected via Fischer connectors 33

Risks Associated with… 34 The Frame and Hull Pelican Box leak Frame is too heavy SubConn connectors leak

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Fall Semester Goals/Accomplishments Select and design major components Thrusters, battery, camera, electronics, connectors, motors, hull, frame, programming language, pseudo-code and software (mission tasks and sensors) Still need to finish design of marker dropper and mechanical grabber, pseudo-code (sensors), and write software (mission tasks), verify that software is compatible with each other Design and build AUV Hull Design and build mounting brackets 37

Spring Goals Write the programs for all subsystems Test and debug Color/shape recognition, sound detection, mechanical grabber and marker dropper, depth control Integrate all subsystems into AUV Full scale testing 38

Risks Associated with… 39 The Schedule Temporary loss of team member Permanent loss of member Drastic change in competition rules Robosub damaged on way to competition Malfunctioning parts Parts are not compatible with each other Team is critically behind schedule

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41 ItemQuantityPrice Main Battery2$ Battery Charger1$80.00 Motors/Thrusters4$3, Hydrophones4$ Microcontroller**1Free CCD Camera3$ Pelican Case1$ Wires/Electronic Kits/Cables & Connectors N/A$1, FrameN/A$ Aluminum Plate 14 in x 12 in x ¼ in1$70.00 Inertial Measurement Unit1$ Total ExpensesN/A$7,500.00

42 ItemPrice Transportation$6, Hotel Accommodations$4, Miscellaneous Expenses$2, Total Expenses$12,000.00

Risks Associated with… 43 The Budget Drastic change in competition rules Robosub damaged on way to competition Malfunctioning parts Parts are not compatible with each other Insufficient equipment funds Insufficient travel funds

Summary of Major Risks: Technical, Schedule, Budget Technical RisksProbability/Consequence Motor/Thruster FailureLow/Serious Battery Failure/damagedLow/Catastrophic Microcontroller-Sensor Communication Error Moderate/Serious Software not executing tasksHigh/Catastrophic Leaks of any kindModerate/Catastrophic 44 Schedule/Budget RisksProbability/Consequence Behind ScheduleHigh/Severe Insufficient Funds (including travel) Moderate/Catastrophic

References Official Rules for 2010 competition: "Official Rules and Mission AUVSI & ONR's 13th Annual International Autonomous Underwater Vehicle Competition." AUVSI Foundation. Web. Sept.-Oct Barngrover, Chris. "Design of the 2010 Stingray Autonomous Underwater Vehicle." AUVSI Foundation. Office of Naval Research, 13 July Web. 09 Nov < anDiegoiBotics.2010JournalPaper.pdf 45