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ITEST Teacher Workshop. MATE Center ITEST Grant Pacific Northwest ROV Regional. Introductions. Rick Rupan – rupan@uw.edu Univ. of Washington Oceanography Dept. ARGO Float Fabrication Wes Thompson - thompson.wes@gmail.com Univ. of Washington Applied Physics Lab Analytical Chemistry
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ITEST Teacher Workshop MATE Center ITEST Grant Pacific Northwest ROV Regional
Introductions • Rick Rupan – rupan@uw.edu • Univ. of Washington Oceanography Dept. • ARGO Float Fabrication • Wes Thompson - thompson.wes@gmail.com • Univ. of Washington Applied Physics Lab • Analytical Chemistry • Fritz Stahr – stahr@ocean.washington.edu • Univ. of Washington Oceanography Dept. • Seaglider Fabrication Center • Jill Zande – jzande@marinetech.org • Marine Advanced Technology Education (MATE) Center • Associate Director & Competition Coordinator • ITEST Project PI
Innovative Technology Experience for Students and Teachers (ITEST) • The ITEST program responds to current concerns and projections about the growing demand for science, technology, engineering, and mathematics (STEM) professionals in the U.S. and seeks solutions to help ensure the breadth and depth of the STEM workforce. • MATE ROV Competitions: Providing Pathways to the Ocean STEM Workforce • $1.2Million, 3-year project funded through ITEST/DRL/NSF • Overarching goal: Use the MATE ROV competition as an engaging platform to prepare middle and high school students for careers in the ocean STEM workforce. • Eight regionals last year, 12 regionals this year • PNW only regional to support ITEST for all three years
ITEST Objectives • Build the support infrastructure for an entry-level ROV competition class by a) providing professional development and student support workshops in afterschool and informal settings; and b) developing, adapting, and enhancing ROV focused STEM curriculum materials. • Increase ocean STEM career awareness and present trajectories to those careers for middle and high school audiences. (Exploring Ocean Careers Course & OceanCareers.com) • Build a cyber learning center to a) foster collaboration and increase communication among students, educators, parents, and working professionals; and b) improve access to STEM instructional resources (MATErover.org) • Evaluate and track project participants to determine the impact on a) students’ STEM knowledge, skill development, and inclination to pursue STEM education and careers; and b) teachers’ confidence in facilitating STEM learning experiences and delivering career information.
ITEST Support for Teachers and Students • Professional development for teachers • Workshops like this one • Teachers leave the workshop with an ROV and sample curricula • Resources for an extended learning course/club at your schools • Course outline and curriculum materials • Tools, materials, and supplies • Materials for up to 3 ROVs • Mentors (professional engineers & technicians, college students and faculty) • Rick, Wes and Fritz as well as our friends at Linn Benton CC and OSU • Information about education and job opportunities • Oceancarreers.com • MATErover.org
MATE Center • What is the MATE Center? • MATE Center is national in scope, but works through regional partnerships. Partners help to create new curricula, collect information from employers, and share 'best practices' related to Marine Technology Education. • What does the MATE Center do? • Workforce assessments • Curriculum development • Summer Institutes for teachers • Technical internships for students • MATE ROV Competitions • Includes one international competition and 21 regional contests held across the US, and in Canada, China, Japan and Scotland • PNW Regional • Getting larger every year, this year expecting 45 teams • Oregon Scout ITEST Competition • Offering a chance for you to test the skills you learn today by bringing a Scout team to competition
Remotely Operated Vehicles • These robots have a long history of salvage, research, exploration • They are connected to the pilot on the surface with a tether • All power and communication happen through this cable • First designs came from the Navy for salvage operations
Navy Advancements Mine Neutralization Advanced Tethered Vehicle
Classes of ROVs How big do these get? How Big Do These Things Get? Classes of ROVs Kaiko, First ROV to Challenger Deep10,916 meters (6.8 miles)
Observation Class ROVs • Small robots (<200 lbs), “low” cost • Primarily used for inspection and observation • Typically all electric with shallow operating depth (~300 m)
The Flying Eyeballs • Thought of as Diver Assistants • Slip into tight or dangerous spaces • Can help place or lift heavy items
Work Class ROVs • Drilling support, construction, inspections, scientific research • Increased payload and depth capability • Hydraulic manipulators
Heavy Work Class ROVsThe Big Guys • Primarily for oil and gas operations • Weigh over 4,500 kg (think minivan) • Work at depths over 3,000 m
Basic ROV Physics • Newton’s Laws • Basic Definitions • What is a force, f=ma • 4 forces for ROVs • Weight • Buoyancy - Archimedes • Thrust • Drag • Centers of … • Gravity • Buoyancy • Thrust
Newton’s Laws • Newton’s First Law • An object in motion will remain in motion unless acted upon by another force • Newton’s Second Law • The relationship between an object’s mass and its acceleration is its force. F=m·a • Newton’s Third Law • For every action there is an equal and opposite reaction
So what forces act on our ROVs? • Weight • A force on an object defined by the product of the object’s weight and the acceleration due to gravity • Buoyancy • The magnitude of the buoyant force acting on an object is equal to the weight of the fluid displaced by the object • Drag • A force that resists the relative motion between and object and the fluid surrounding it • Thrust • An energy requiring, propulsive force used to control vehicle motion
Weight • The mass of an object is pulled towards the center another object at a given acceleration. This is gravity, and on Earth is equal to 9.8 m/s2 • Gravity is an acceleration and can be used in Newton’s Second Law, F=m·a • Weight is the force exerted on a mass by gravity. Inserting this to Newton’s Second Law gives F(weight)=m·a(gravity) or W=m·g
Buoyancy An object in a fluid will displace an amount of fluid equal to its volume. The volume is used to determine the density of the object (D = mass/vol). To determine buoyancy, the density of the fluid and the density of the object can be compared. Most ROVs are close to neutrally buoyant. This allows the operator to control the vehicle’s position with a motor, rather than try to change its buoyancy. Objects that float upward are positively buoyantDobject < Dfluid Objects that sink are negatively buoyant Dobject> Dfluid Objects that neither rise nor sink are neutrally buoyant Dobject= Dfluid
Drag • Drag resists the movement of an object through a fluid • The shape of your vehicle will determine its drag • Drag increases dramatically as speed increases • Reduce the drag to more efficiently propel your vehicle through the water
Thrust • Propellers accelerate water away from their faces (Newton’s Second) • Water is forced away from the propeller which in turn pushes the vehicle in the opposite direction (Newton’s Third)
Basic Physics • Center of Gravity • Balance your ROV on your fingers • Make sure weight is evenly distributed • Center of Buoyancy • Floatation above weights!! • The further apart your weights and floats, the harder it is to flip your ROV • Center of Thrust • Keep this close to your center of gravity • That doesn’t necessarily mean your thrusters have to be dead center in your ROV • They can be spread out (allows for faster turning) but align your centers
Center of Gravity • The imaginary center of the weight of your vehicle • If symmetrically weighted, located at geometric center
Center of Gravity • CG will change as weight is added to your vehicle • If you are asymmetric with your weight distribution your CG will change location
Center of Gravity • If not properly ballasted, your vehicle will tilt in water to align the CG with the heaviest part of your vehicle
Center of Buoyancy • CB is determined by the floatation of your vehicle • CB will always be in the same vertical plane as your CG
Center of Buoyancy • The vehicle will always try to orient itself with the CB over the CG • The greater the distance CG:CB the more stable the vehicle in water
Center of Thrust • CF is difficult to describe as a center point. It is better described as a line running through the CG of the vehicle • Symmetrical thrust around this line will not push the vehicle in any other direction but forward
Center of Thrust • If thrust is applied asymmetrically, the vehicle will rotate around the CG
Competition Class ROVs • Squares have easy to find center of gravity • High Flotation • Low Weights • Thrusters aligned with center of gravity
Electricity • Flow of electrons • Voltage/Amperage • Series and Parallel • Battery • Fuses • Switches • Spst, dpdt • Motors • Volts and amps
Electricity and Circuits • Charge • Electrical property associated with protons (+) and electrons (-) • Opposite charges attract each other (like magnets) • Electricity is the flow of charge as the two opposite charges attract each other • Batteries separate charges through a chemical imbalance • This imbalance generates an electromotive force (voltage)
Electricity and Circuits • Current (Amps) • The flow of charged particles from one location to another • Conventionally said to move from (+) and towards (-) • Voltage (Volts) • Separate charged particles and generate a potential • This potential is voltage • Think of it as pressure to push current through the wires • Resistance (Ohms) • Electrical equivalent to friction • Converts electrical energy to heat and causes voltage to drop • Resistance is determined as the amount of voltage needed to force a current through an object
Electricity and Circuits • Ohm’s Law – V = I x R • Voltage (V) has units of volts • Current (I) has units of Amps • Resistance (R) has units of Ohms • Most useful equation in basic electronics V I x R
Electricity and Circuits Current flows through loops called circuits which have three fundamental parts • Voltage source: Battery, wall outlet, etc. • Load: something that does work with electricity, a light source, motor, heater, etc. • Switch: When closed, completes the circuit and allows current to flow. When open, breaks the loop and current stops. + -
Electricity and Circuits • Voltage Source • Anything that can separate + and – charges • Batteries separate charges chemically • Load • Anything that converts electricity into heat or work • Incandescent light bulbs heat a thin filament to white hot temperatures to produce light • Motors convert electricity to motion • Switch • Switches create breaks in the line to stop the flow of electricity or fix those breaks to allow the flow • Fuse – Important part of ROV circuits • Small wire that will melt when too much current flows through it • Safety mechanism to prevent too much current flow through your system • Always placed on positive lead as close to voltage source as possible. Will work the same on negative lead, however the circuit before the fuse will still be live and can be a safety hazard.
Switches • Switches create breaks in the circuit loop stopping the flow of charge • The most simple switch is called ‘single pole, single throw’ • Either on or off, like a light switch • A little more complicated is the ‘single pole, double throw’ • Like an ‘either / or’ switch, send current in either this direction or in this other direction
Switches - DPDT • The switches we use in our control box are called ‘Double Pole, Double Throw’ • Exactly like two SPDT switches put together • This allows control of four lines with one switch • Two positive and two negative lines
Switches – H Bridge • An H-Bridge allows current to change direction based on a switch • For us, this means our motors can spin backwards and forwards • When we make the control box, we will connect our motors to the top two pins of the switches (pins 3 and 6)
Electricity and Circuits Series Circuit • Two or more components connected end to end so current flowing through one component must then flow through the next • Current flowing through will always be equal but voltages may not be (depends on the resistance of the component, Ohm’s Law) • The voltage from one end to the next will be equal to the sum of the voltages across the components + -
Electricity and Circuits Parallel Circuit • In this arrangement, components are exposed to the exact same voltage, however current will be divided among the components. • Current does not need to (and probably will not) be equal across each component (again resistance and Ohm’s Law) - +
Intro to Soldering • Wet sponge! • The hot iron easily oxidizes and a wet sponge will clean this off. A dry sponge can damage the tip. • Clean iron • Every time you pass over the sponge, clean your iron. When you first pick it up and when you last place it back, clean your iron! • Heat Shrink First • Heat shrink covers your solder connections so it does not short circuit and will waterproof connections as well. • Good mechanical connection • Solder is not a strong metal. A good physical connection by twisting the wires together is necessary to ensure they don’t break apart. • Tin your tip • Quickly touch solder to the tip of the iron to leave a small bead of molten solder on the tip. This facilitates the flow of heat into your joint. Note: the side of the tip of the soldering iron is hotter than the point • Touch the molten bead to your wire joint • Heat will flow into the wire, touch the solder to the wire and watch it flow • Know where cord is? Don’t burn it, others or you
Control Box • Switches • Strip and crimp 3x blue and 3x orange wires • ¼” strip on either end • Crimp forked terminal to each end. Metal to metal (crimp to wire itself) • Strip 2x white and 2x black wires • Crimp 2x red into a Y shape, same with black • May have to untwist and thin black and white wires down by half to insert two into fork terminal