Question of the DAY DEC 11
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Transcript of Question of the DAY DEC 11
Question of the DAY DEC 11
• Which step of EDP evaluates the pros and cons of different ideas?
• A. STEP 3• B. STEP 4• C. STEP 5• D. STEP 6
DO NOWDEC 11
• Discuss the quantities of velocity involved in the throwing of a projectile (THINK Vectors!!!).
• Explain your answer using mathematic principles.
DO NOW ANSWERED DEC 11
• Both Vx and Vy are equally important. • Equal horizontal and vertical velocities will provide the
projectile with the maximum distance in travel.
• If Vx is greater than Vy, the projectile’s trajectory will push it downward into the ground.
• If Vy is greater than Vx, the projectile’s trajectory will push it upward causing it to lose energy and shorten the distance it travels.
• How do you achieve equal horizontal and vertical velocities?
AGENDA DEC 11
• BIG QUESTION: How does EDP affect the design and construction of a solution to a proposed problem?
• 1. Question of the Day and DO NOW• 2. Newspaper Tables Challenge II• Once you finish your 2nd Design, work on rolling the
newspaper and shaping the supports into a square/triangle shape and RETEST.
• 3. Introduce Catapult Challenge Project• 4. Review and Homework
Question of the DAY DEC 12
• Torsion can be defined as a
• A. Rotational Force• B. Twisting force• C. Linear Force• D. Pulling force
DO NOW DEC 12
• What is the acceleration of an object due to gravity in SI units?
• Discuss the effects gravity has on the workings of a catapult or trebuchet.
DO NOW ANSWERED DEC 12
• 9.8 meters/second squared• Gravity is the force exerted on all objects by the Earth that are on
or near its surface.
• Gravity will ultimately pull any object including a projectile launched by a siege engine to the ground.
• It is also the simple force used to power the trebuchet.• The device believed to be the most effective siege weapon prior to the
advent of gunpowder and the cannon.
AGENDA DEC 12
• BIG QUESTION: How does EDP affect the design and construction of a solution to a proposed problem?
• 1. Question of the Day and DO NOW• 2. Newspaper Tables II Results/Questions• 3. CATAPULT CHALLENGE PROJECT• 4. Medieval Siege Video• Complete Video Guide
• 5. Review and Homework• Tomorrow: Meet in 417• We will then go to the library.
CATAPULT CHALLENGE
STEM Trimester 2 2013
CATAPULT CHALLENGE TEAMS
• You will work in your teams to complete this project.
How to build a catapult in eight easy steps
• Watch the following video documenting the tedious and very demanding process of building a medieval trebuchet.
MEDIEVAL SIEGE
• http://www.youtube.com/watch?v=5WDiW1WDyrA
AGENDA DEC 13
• BIG QUESTION: How does EDP allow you to build a working solution to a proposed problem?
• 1. LIBRARY Research Day• We are on the island
• 2. Catapult Teams• 3. Objectives
TODAY’S OBJECTIVES DEC 13
• Begin some informal research on the CATAPULT CHALLENGE PROJECT
• Write down websites and other useful links.• Make a team decision to build a CATAPULT or a
TREBUCHET• Any research, brainstorming, discussion, ideas, sketches,
websites, video clips, or anything else to do with this project must be recorded.• Elect a Note Taker (Remember the EDP!)• Use your notebook like a journal• Write EVERYTHING down• Required to earn maximum points for project
Question of the Day DEC 16
• When constructing a trebuchet, which component design will be most critical to a successful throw?
• A. Framework• B. Wheels• C. Throwing arm• D. Sling
DO NOWDEC 16
• Work with your Catapult teams.• BRAINSTORM for 10 minutes about websites
and ideas you have found through your RESEARCH.
• Ask yourselves which part of the project will be most challenging for you.
• GET ORGANIZED!!!
AGENDA DEC 16
• BIG QUESTION: How does EDP affect the design and construction of a solution to a proposed problem?
• 1. Question of the Day and DO NOW• 2. CATAPULT CHALLENGE PROJECT Presentation• 3. Medieval Siege Video• Complete Video Guide
• 4. Review and Homework
MEDIEVAL SIEGE
• http://www.youtube.com/watch?v=5WDiW1WDyrA
Question of the DAY Dec 17
• A block and tackle utilizing a double pulley reduces the amount of force required to lift objects. How much force is required to lift a automobile with a mass of 5400 kg?
• A. 5400 N• B. 2700 N• C. 1350 N• D. 900 N
DO NOW DEC 17
• Work with your Catapult Teams to design your presentation.
• Lay out each section of your presentation and what you want to include in each one.• Include diagrams, video clips, images, and other useful
information.• GET ORGANIZED!!! TEAMWORK!!!
• We will be in the library on Friday.
• Presentations are DUE on MONDAY DEC 23.• BE PREPARED TO PRESENT!!!
PRESENTATIONS
• ALL TEAMS MUST BE PREPARED TO PRESENT.
• ANY TEAM NOT READY WILL LOSE 20% OF THEIR GRADE.
• Refer to the grading rubric for a breakdown of scoring categories.
AGENDA DEC 17
• BIG QUESTION: How can energy be used to launch a projectile?
• 1. Question of the DAY and DO NOW• 2. Hand in Medieval Siege Video Questions• 3. Catapult Physics – Forces• 4. Measurements and Scaling• 5. Catapult Teams – Presentations • DUE MONDAY DEC 23
DO NOW Jan 2
• You are asked to design a new touring bicycle for the US Postal Service team.
• Describe how you would go about this process. Use EDP as a framework
DO NOW ANSWERED Jan 2
• Find out if the riders have any specific requests (Step 1)
• Determine a budget, building materials, and how quickly they need it (2).
• Research existing models and share new ideas. Collect data on what works (3).
• Choose a few ideas to develop. Different frame materials (aluminum, titanium, carbon fiber). Notes and drawings (4)
DO NOW Answered Jan 2
• List pros and cons of each bicycle design (5).• Pick the best idea with your team. Use
multiple parts from different ideas (Frame material from one idea and frame geometry from another idea 6).
• Build a bike. Does it all fit together? (7)• Get out and RIDE! Make improvements based
upon rider feedback, input, suggestions (8)
THE PHYSICS OF A CATAPULT
• Catapults use stored energy to hurl a projectile without the use of an explosive charge. The three primary energy storage mechanisms are tension, torsion, and gravity. (Real-World Physics)
TENSION
• Tension is the pulling force exerted by a string, cable, chain, or similar solid object on another object.
• Tension is the opposite of compression force.
• Measured in Newtons (N).
• PE when drawn or taut (C)• Energy = 0 at rest (B)• KE when released (A)
Examples of Tension
• Bows and Crossbows
• Composite bow is a traditional bow laminated together.
• When the bow is drawn, the sinew (stretched on the outside) and horn
• (compressed on the inside) store • more energy than wood for the • same length of bow.
Examples of Tension
• Muscle Fibers create tension during a muscle contraction.
• Muscle fibers slide across one another producing tension.
TORSION
• Torsion is the twisting of an object due to an applied torque.• Torque is a rotational force.
• An object tends to rotate about a fixed object.Torque = Force x Lever Arm Distance
Torque
Examples of Torsion
• Flexible elastic object that stores mechanical energy when it is twisted.
• Torsion bar suspensions
Examples of Torsion
Counterweight
• A counterweight is an equivalent counterbalancing weight that balances a load.
Question of the DAY DEC 18
• Which of the following is not measured in Newtons?• A. Tension• B. Compression• C. Weight• D. Stress
DO NOW DEC 18
• You have been asked to build a workbench for the Art Department.• List five factors you would consider when
designing/assembling the table.• Briefly explain why each factor is important.
• Cost of the table is not a factor.
DO NOW Answered DEC 18
• 1. Size of the table• 2. Type of material to build it with• Must meet the demands of the class environment
• 3. Location of the table (Space limitations)• Indoor/Outdoor (will also affect the materials used)
• 4. Uses of the table• Art work, painting, sculpting, pottery
• 5. Dimensions of the table (Height, width, Length)• 6. Ease of maintenance and cleaning.• 7. Who will be using it?• Age of students
AGENDA DEC 18
• BIG QUESTION: How can energy be used to launch a projectile?
• 1. Question of the DAY and DO NOW• 2. Catapult Physics – Forces• 3. Measurements and Scaling• 4. Review and Homework• 5. Catapult Teams – Presentations • DUE MONDAY DEC 23
Counterweight
When a counterweight is greatly overbalanced on one end of a lever, it can produce large amounts of energy.
Potential Energy vs. Kinetic Energy
Counterweight is not moving vs. moving.
The Mangonel Catapult
• Catapults work by storing energy in twisted ropes.• They function much like an archery bow.• The tension stored is released as kinetic energy.
The Trebuchet
• The trebuchet uses a counter-balance weight to rapidly rotate the throwing arm when the weight is released.
Generating Energy
• The twisted rope is commonly referred to as a torsion bundle.
• It consists of several lengths of rope with the arm inserted in between them.
• The rope is then twisted manually on both sides of the arm using levers.
• Upon release, the torsion bundle rotates the arm at high speed, launching the payload.
Question of the DAY Dec 19
• A wooden bridge has a width of 28 feet and a length of 120 feet. Accurate testing of the bridge’s efficiency requires you to build a scale model of it. If the scaled width of the bridge is 7 feet, what is the scaled length of the bridge?
• A. 20• B. 28• C. 30• D. 40
DO NOW DEC 19
• List the eight steps of the EDP.
•Which step do you believe is the most important to the success of your Catapult Challenge? • Explain your answer.
AGENDA DEC 20
• Big QUESTION: How do scale model drawings assist you in building a successful catapult/trebuchet?
• 1. Continue Measurements and Scaling• 2. Project Presentations: DUE Monday DEC 23 • ALL TEAMS MUST BE PREPARED TO PRESENT. ANY
TEAM NOT READY WILL LOSE 20% of THEIR GRADE. • Practice your presentations!!!• Share your presentation with each other.HOMEWORK: Measurements/Scaling Activity DUE TomorrowComplete Designing a Garden: DUE MONDAY DEC 23
Media Center Expectations for Sept 20
• 1. All teams should finish their presentations first.• 2. I will check with every team in the Media Center to make
sure you are on task.• 3. I am looking for completed presentations including
diagrams, video clips, animations, as well as an order of presentation. Slides each team member will be presenting. Know your information. PRACTICE. Being unprepared will affect your grade.
• 4. All team members must have a copy of the presentation. Being ABSENT is NOT an EXCUSE!!!
• 5. Continue with your RESEARCH. BE ORGANIZED!
AGENDA DEC 23
• BIG Question: What benefits do research provide to the completion of the Catapult Challenge?
• 1. Catapult Challenge Progress Presentations• 2. All teams must be prepared to present.• 3. HOMEWORK• HAPPY HOLIDAYS!!!• MERRY CHRISTMAS and HAPPY NEW YEAR!!!
Question of the DAY Jan 2
• You need to review two designs for a project you are working on. It is necessary to reevaluate the pros and cons of each design.
• You would check your notes for which EDP step to do this…
• A. Step 4• B. Step 5• C. Step 6• D. Step 3
DO NOW Jan 2
• Underwater exploration is the new frontier for many kinds of research.• A new type of self-contained submersible is
needed to expand current capabilities of exploration.• Apply the steps of EDP to the plan and design of
a deep-sea vehicle.• What questions need to be asked throughout the
process?
DO NOW ANSWERED Jan 2
• Special requests/requirements (Step 1)• Determine a budget, building materials, and
how quickly they need it (2).• Research existing models and share new ideas.
Collect data on what works (3).• Choose a few ideas to develop. Include life
support systems, power/fuel sources, and frame construction.
DO NOW Answered Jan 2
• Weight he pros and cons of each design. Which is the most efficient at solving the problem (5).
• Move forward with the best idea. Include facets of working models and improve upon them (6).
• BUILD IT! Remember the difference between a fault and a weakness.(7)
• Test it. Use it in various underwater conditions. Unmanned and manned controlled tests. Invite experts in the field to review and critique your designs . Make improvements based upon their input and your test results. (8)
AGENDA Jan 2
• BIG QUESTION: How does engineering evolve to build safer machines?
• 1. Question of the Day and DO NOW• 2. Finish Presentations• 3. The duty of responsible engineering• 4. Introduce Engineering Critique Project• 5. Closing Thoughts and Review
Engineering
• The role of the engineer is to respond to a need by building or creating something along a certain set of guidelines (or specifications) which performs a given function.
• Devices, plans, or creations should perform its function without fail.
Engineering
• Engineers weigh different design choices on their merits and choose the solution that best matches the requirements.
• The crucial and unique task of the engineer is to identify, understand, and interpret the constraints on a design in order to produce a successful result.
• It is usually not enough to build a technically successful product; it must also meet further requirements.
AGENDA Jan 6
• BIG QUESTION: How does engineering evolve to build safer machines?
• 1. Finish Presentations• 2. Hand in homework• 3. Research Day – Center Island in Library• 4. Engineering Disasters Critique Project• 5. Closing Thoughts and Review
Research Day: Expectations and Objectives JAN 6
• Research and Select an Engineering Disaster for your Project.• Be sure that the disaster you choose meets all of the criteria of the project as per the
handout.
• Begin working on sketches and diagrams of a buildable and working catapult/trebuchet design.• Consider the following…• Size of overall device• Parts you will need• Dimensions of components• Energy mechanisms – Torsion or Counterweight• Sling Assembly, Length of throwing arm, torsion, Placement of Axle• Frame design/reinforcements
Question of the Day Jan 7
• The most important responsibility an engineer has is to
• A. create the most cost-efficient (cheapest) design.• B. meet all of the constraints and criteria of the project.• C. create a design with the greatest factor of safety• D. create the safest design while considering cost and
materials
DO NOW Jan 7
• 417 Enterprises is a company that specializes in producing extreme conditions equipment. One of their products is a high tensile braided rope used for rescue operations and high-altitude expeditions. They recently chose a new supplier for the nylon used in the rope. It is cheaper and the new supplier says the nylon fibers are the strongest available today.
• Two climbers were recently killed in an accident on Mt. Everest when one of the ropes purchased from 417 was unable to support the weight of three climbers and their gear. The weight was well under the maximum limit of the rope. Upon investigation, the rope did not appear to be cut or damaged.
• Which party is at fault? Support your answer.
DO NOW ANSWERED Jan 7
• 417 Enterprises is liable for the defective rope they manufactured and sold.
• The climbers did not exceed the recommended maximum load rating of the rope.
• The fault most likely lies with the new nylon purchased for the rope.
• It is the responsibility of 417 to retest the ropes using the new nylon.• Main component (nylon) of the rope has been changed.
• The manufacturing process of the rope may have weakened the overall strength of the nylon.
• The nylon manufacturer may also have some liability.
AGENDA Jan 7
• BIG QUESTION: How does engineering evolve to build safer machines?
• 1. Finish Presentations• 2. Role and Responsibilities of an Engineer• 3. Catapult Challenge EDP Steps 5 and 6• 4. Closing Thoughts and Review
Engineering
• Engineers take on the responsibility of producing designs that will perform as well as expected and will not cause unintended harm to the public at large.
• Engineers typically include a factor of safety in their designs to reduce the risk of unexpected failure.
• However, the greater the safety factor, the less efficient the design may be.
• What factors may affect limitations of a factor of safety?
Factor of Safety
Material StrengthFactor of Safety = _________________
Design Load
• Design load is maximum load a part should ever see in service.
• I-beam material strength = 3000 tons (Maximum before failure)• Design load applied to I-beam = 1000 tons• Factor of Safety = 3
Engineering
• Engineers must struggle to design in such a way as to avoid failure, and, more importantly, catastrophic failure.
• Result in loss of property, damage to the environment, and possibly injury or loss of life.
• With analysis and study of engineering disasters, modern engineering designers can learn what not to do and how to create designs with less of a chance of failure.
Question of the Day Jan 8
• When calculating factor of safety, the material strength is defined as
• A. the least amount of weight a material should be exposed to• B. the maximum amount of load that a part will see in service• C. the maximum load a material can withstand before failure• D. the safest amount of weight a part should be exposed to
DO NOW Jan 8
• A new proposal has been given to your engineering firm. A new product has been designed with flexible, gold (Au) joints. These joints need to flex in order to withstand various environmental conditions the product will be exposed to. The product is a new type of “rover” which can collect data and specimens within extremely hot or cold conditions. It has the same capabilities as other “rovers” available on the market. Most rovers of this type cost anywhere between $50,000 to 60,000. This new “rover” will cost $80,000.
• Evaluate the proposal before it can go into production.
DO NOW Answered Jan 8
• Considerations….• 1. COST – Gold will drive up price of the product.• Is this the only reason why it costs $20,000 to 30,000 more than other
models?
• 2. Need for Gold – why is gold needed?• Gold is a malleable metal with a low melting point.• Is this the best material for the job?• Alternate material that can be used?• Still needs to be tested!
AGENDA Jan 8
• BIG QUESTION: How does engineering evolve to build safer machines?
• 1. Question of the Day and DO NOW• 2. Role and Responsibilities of an Engineer• Engineering Disasters Video Clips
• 3. Catapult Challenge EDP Steps 5 and 6• 4. Closing Thoughts and Review
Identifying Potential Risk
• Consider the various forms of transportation and travel available to us.
• Which method of transportation do you believe is the most dangerous?
• SUPPORT your answer with facts/data/examples.• BE READY to share your answer with the class.
Modern Engineering
• What are the general opinions and fears of the public?
Disasters are identified by the public’s perception of risk.
Perception of Risk
• In 1992, roughly the same number of fatalities occurred (in the United States) in transportation accidents involvingairplanes (775)trains (755)bicycles (722)
• Public perception of risk is by far the greatest with air travel.
AGENDA Jan 9
• BIG QUESTION: How does engineering evolve to build safer machines?
• 1. RESEARCH DAY – On the Island• 2. Role and Responsibilities of an Engineer• Engineering Disasters Video Clips
• 3. Catapult Challenge EDP Steps 5 and 6• 4. Closing Thoughts and Review
Engineering Disasters
• http://www.youtube.com/watch?v=e6PKIiT_T8Q
• 8:52• 17:55
Question of the Day Jan 14
• Which of the following is most difficult for engineers to account for when designing a solution to a problem?
• A. Maximum load applied to the structure• B. Quality of building materials• C. Integrity of foundation materials• D. Natural phenomenon
DO NOW Jan 14
• You have been asked to design a new type of rocket car. It will be used to attempt to break the current land speed record held by Royal Air Force pilot Andy Green. It stands at an average of 763.05 mph (1227.96 km/h) over a 1 mile distance. This is the only supersonic land speed recorded to date.
• Brainstorm with your teammates and compile a list of factors and considerations that must be included in a design for this type of vehicle.
DO NOW ANSWERED Jan 14
• Materials to build the vehicle (what is the cost constraint if any)
• Tires for maximum traction (where will vehicle be tested)
• Type of propulsion system (Turbofan)
• Safety mechanisms to slow and stop vehicle (drag chute)
AGENDA Jan 15
• BIG Question: What is the role of an engineer?
• 1. Question of the Day and DO NOW• 2. Role of the Engineer• 3. FRIDAY Jan 17 QUIZ on Physics of a Catapult and
Role of the Engineer• 4. Blueprints and Parts Lists – Special Parts• 5. STUDY for QUIZ
The Speed of Sound
• http://www.youtube.com/watch?feature=endscreen&NR=1&v=gWGLAAYdbbc
AGENDA Jan 16
• BIG Question: What is the role of an engineer?
• 1. Question of the Day and DO NOW• 2. Space Shuttle Challenger Disaster• 3. FRIDAY Jan 17 QUIZ on Physics of a Catapult and Role of
the Engineer• 4. Blueprints and Parts Lists – Special Parts• 5. STUDY for QUIZ
Space Shuttle Challenger
• January 28, 1986• The Challenger disintegrated 73 seconds into its flight after lift-off.• All 7 crew members were killed.
• The O-rings, as well as many other critical components, had no test data to support any expectation of a successful launch in such conditions.
• The lowest safe launch temperature was confirmed at 4o degrees F.• The morning of the launch was 18 degrees F.
Causes of Failure
• Insufficient knowledge ............................... 36% Underestimation of influence ......................... 16% Ignorance, carelessness, negligence .................. 14% Forgetfulness, error ................................. 13%
Relying upon others without sufficient control ....... 9% Objectively unknown situation ........................ 7%
Poor definition of responsibilities ............. 1% Choice of bad quality ................................ 1% Other ................................................ 3%Conducted by the Swiss Institute of Technology, Zurich
AGENDA Jan 16
• BIG Question: What is the role of an engineer?
• 1. Question of the Day and DO NOW• 2. Space Shuttle Challenger Disaster• 3. FRIDAY Jan 17 QUIZ on Physics of a Catapult and Role of
the Engineer• 4. Blueprints and Parts Lists – Special Parts• 5. STUDY for QUIZ
GOOGLE buys Robotics Firm
• http://www.youtube.com/watch?v=diaZFIUBMBQ
AGENDA NOV 5
• BIG QUESTION: How can building a prototype provide you with opportunities to improve your design?
• 1. CATAPULTS• 2. Other materials• 3. Objectives• 4. Closing Thoughts and Homework• Model Airplane Challenge and Webquest
MODEL AIRPLANE CHALLENGE
• If you need to finish testing your model airplanes, you must do so today!
• Results and your design notes/diagrams are due TODAY by the end of this period.
• Please place them in the HOMEWORK BOX before you leave class.
QUESTION of the DAY
• When assembling your catapults, it is important to be careful when placing screws because
• A. they won’t secure the wood if they are too close together
• B. the wood may split if the screws are placed along the outer edges of the wood
• C. they may protrude along the length of the wood• D. components of your catapult may be weakened
AGENDA NOV 6
• BIG Question: How can building a prototype provide you with opportunities to improve your design?
• 1. SAFETY!!! WEAR PROTECTIVE EYEWEAR AT ALL TIMES!!!
• 2. Assembly of your catapults• 3. Preparing components• 4. Closing Thoughts
• http://www.matscieng.sunysb.edu/disaster/
CONSTRUCTION of CATAPULTS
• Measure and mark where you will need holes drilled into the components of your catapult.
• GLUE your framework and base together.
• Place paper towels under any glue points – Let’s keep the classroom clean.
• Once your frame has been glued together and has dried, you may them begin to place screws into the wood.
Placing Screws
• Be careful with where you insert screws to hold your framework together.
• Avoid placing screws too close together or along the edges of the wood.
• Place one screw and then wait before adding a second.
• This may cause components to crack or split.
• Inspect the components as you begin putting everything together.
NEW PARTS
• If you require any replacement parts, you must write it down on a separate sheet of paper with the quantity/specs you need.
• Include the names of the members in your team.
• State the reason why you require new parts.
CATAPULT CHALLENGE
• EDP STEPS 7 and 8• YOUR HOMEWORK• Bring in screwdrivers (Phillips
Head) and any other materials/tools you will need to complete your catapults.
TODAY’S OBJECTIVES
• 1. Get your CATAPULT Parts• 2. Inspect all of your components.• ALL PARTS were cut as per your diagrams/specs.• Make sure they match the Specifications on your Parts
Lists.• 3. Clean up all of your parts… SAND them down to
remove any rough/sharp edges.• 4. Organize all of your notes/information from your
design steps.• I will return your parts list and spec sheets.
MISSING PARTS
If you need any additional components not on your parts list
ORIf you are missing anything/something is not cut
to your specs.
I NEED TO KNOW!!! So I can get teams what you need.
PRE-BUILD INSPECTION
• Lay out all of your parts to make sure your catapult can be constructed.
• DO NOT begin to assemble anything with screws yet!!!
• Remember to include parts for the projectile basket and the torsion handle or handles.
PLANNING
• Measure and mark where you need holes drilled • Indicate the diameter of the hole.
• Angled supports may require angled cuts.• Measure these cuts and mark them on the wood
sections. (USE PROTRACTORS/RULERS)