lesson plans for uruguay ver003
DESCRIPTION
Tisp MontevideoTRANSCRIPT
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Sort It Out Critical LoadPulleys and ForceShip the Chip
Christopher Lester
Yvonne PelhamMoshe Kam
D.G. Gorham
TISP: Uruguay
9–10 May 2009
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Welcome
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Package design and the engineering behind shipping products safely
Exercise 1:
Ship The Chip
+Ship the Chip
Learn about engineering product planning and design
Learn about meeting the needs of the customer and society
Learn about teamwork and cooperation
Objectives
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+Ship the Chip
Manufacturing EngineeringPackage design, manufacture and test
Material properties and selection
Real world application of mathematics
Teamwork
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Students will learn…
+Ship the Chip
Design a package that will securely hold a potato chip and protect it from breaking when dropped
Construct the lightest package to get the highest score Overall score based on:
Weight of the package Volume of the package Intactness Score
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The Challenge
+Ship the Chip
1. Sketch a design on the worksheet Label your worksheet with Table # and Team Name
2. Construct a model of your package
3. At a test station, drop the package from a height of 1.5 meters
4. Open your package and examine the chip
5. Calculate and record your score
6. Using a second kit, redesign and construct a new package Record the second design on the worksheet
7. Label your package with Table # and Team Name
8. Submit your worksheet and package to the Test Team for overnight testing
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Procedure
+Ship the Chip
Cardboard – 22 cm x 28 cm 10 Craft sticks 6 Cotton Balls String – 91 cm Plastic wrap – 1 sheet of 22 cm x 28 cm 10 Toothpicks Foil – 1 sheet of 22 cm x 28 cm Paper – 1 sheet of 22 cm x 28 cm 1 Mailing label 1 Potato Chip
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Materials
+Ship the Chip
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Tools and Accessories
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Intactness score :
100: like new, perfect
50 : slightly damaged; cracked but still in one piece
25 : broken in 2 - 5 pieces
5 : broken in 6-20 pieces
1 : broken into more than 20 pieces; crumbled
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Ship the ChipScoring
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_ _ _ _
Intactness ScoreOverall Score
Weight in Kg Volume in cm
+Ship the Chip
We will imbed the package in the smallest-volume rectangular prism that contains it
We will calculate the volume of the prism; Width x Length x Height For example : 3cm x 4cm x12cm =144 cm3 in the prism
shown below
If your package weighed 100g and had a volume of 800 cm3 and the chip has arrived broken in 3 pieces:
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Calculating Volume
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_ _ _ _
Intactness ScoreOverall Score
Weight in Kg Volume in cm
25_ 0.3125
0.1 800Overall Score
+Ship the Chip
1. Sketch a design on the worksheet Label your worksheet with Table # and Team Name
2. Construct a model of your package
3. At a test station, drop the package from a height of 1.5 meters
4. Open your package and examine the chip
5. Calculate and record your score
6. Using a second kit, redesign and construct a new package Record the second design on the worksheet
7. Label your package with Table # and Team Name
8. Submit your worksheet and package to the Test Team for overnight testing
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Procedure
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The engineering behind industrial sorting processes
Exercise 2:
Sort It Out!
+Sort It Out
Learn about engineering of systems
Learn about coin manufacturing processes
Learn about teamwork and cooperation
Objectives
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+Sort It OutSorting through History
Miners panning for gold
Quality control in food and other industries
Bottle sorting for recycling
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+Sort It OutDifferent Types of Sorting
Lighting
Digital I/O & Network
ConnectionFrame
Grabber
Part Sensor
Camera &
PC platform
Inspection software
Optics
Image Processing:Off-the-shelf cameras, frame grabbers, and image-processing software used to develop a casino-coin sorting system
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+Sort It OutDifferent Types of Sorting
Material Properties of Coin: Current run through left
coil, creates magnetic field. Magnetic field passes
through and is attenuated by coin
Right coil receives magnetic field, creates measurable current with different value depending on the coin
Coin in Center
Transverse line represents direction of magnetic field
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Mixed coins come from a variety of sources and must be sorted out before they can be redistributed Coins from vending
machines Coins from parking meters
Also helpful to identify fake or foreign coins
Sort It OutWhy Coin Sorting is Needed
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Mixed coins are Sorted Rolled Re-circulated
through banks and businesses
Sort It OutWhy Coin Sorting is Needed
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Groups of 2
You are a team of engineers hired by a bank to develop a machine to sort coins that are brought in by customers.
Must mechanically sort mixed coins into separate containers.
In our experiment we use washers: ½ Inch 1 Inch 1¼ Inch 1½ Inch
Sort It OutYour Turn
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+Sort It Out
How good is it?
1: “Distance” performance index:
A washer that does not get sorted has maximum Derror = 3
Your Turn
½in 1in 1¼in 1½in1
Distance from correct binhere, Derror = 2 bins
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½
½
½
½
½
1½1¼11 1 1 1¼
1¼1¼
1¼ 1½
1½ 1½
+Sort It Out
How good is it?
2: “Percentage” performance index:
Your Turn
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½in 1in 1¼in 1½in1
11
½
½
½
½
½
1½1¼11 1 1 1¼
1¼1¼
1¼ 1½
1½ 1½
# of washers incorrectly identified
Total # of washers to sort 405%
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Materials: glue, tape, paper or plastic
plates, cardboard, scissors or hole punch, foil, paper, cardboard tubes
washers
Design (draw) a mechanical sorter that can separate the ½in, 1in, 1¼in, 1½in washers
Input: either Parallel – all washers are
inserted at start of your sorter together; or
Serial – washers are inserted at start of your sorter one at a time
Output: Each size of washer in its own physical container
Sort It OutYour Turn
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+Sort It Out
At your table, choose 2 groups to build a parallel sorter; the other 2 groups will build a serial sorter
You will have 45 seconds to allow your sorter to operate
Predict the value of the two performance indices for your design
Construct your sorting mechanism
Test it!
Can you do better?
Your Turn
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+Sort It Out
Did your sorting mechanism work? If not, why did it fail?
What were your performance index values?
What levels of error would be acceptable in: Medical Equipment manufacturing? Nail manufacturing?
What redesigns were necessary when you went to construct your design? Why?
Conclusion
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All about force and how pulleys can help reduce it
Exercise 3:
Pulleys & Force
+Pulleys & Force
Learn about pulleys and pulley systems
Learn how using multiple pulleys can dramatically reduce required force
Learn how pulley systems are used in machines and impact everyday life
Learn about teamwork and problem solving in groups
Objectives
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Fixed Pulley Movable Pulley
Pulleys & ForceBasics of Pulleys: Two orientations
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The tension in the rope, T, is always the same everywhere
Fixed pulley allows for change in direction of applied force
Sum of the forces: vertically
2 T = 100 N T = 50 N
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Compound Pulley
Pulleys & ForceBasics of Pulleys
+Pulleys & ForceMechanical Advantage
Mechanical Advantage (MA) isthe factor by which a mechanism multiplies the force or torque put into it.
Ideal MA:
Actual MA:
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This movable pulley system has a mechanical advantage of 2
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Work is the amount of energy transferred by a force acting through a distance
Work = Force x Distance
Work = Force x Distance A bigger mechanical
advantage decreases the force required, but increases the distance over which it must be applied
The total amount of work required to move the load stays the same
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Pulleys & ForceWork
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The ratio between Actual and Ideal mechanical advantage is Efficiency
Frictionless system = 100% Efficiency
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Pulleys & ForceEfficiency
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Pulleys have long been used on sailing ships to handle the rigging and move the sails
Even with large mechanical advantages, it still takes many people to do the work!
Pulleys & ForcePulleys in the World
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Pulleys are used in elevators to change the direction of the tension in the cable, reduce power required of lift motor
Pulleys & ForcePulleys in the World
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Industrial cranes lift large loads for construction and transportation
Pulleys & ForcePulleys in the World
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+Pulleys & ForceMeasuring Tension
Spring Scale
Calibrate: Hold spring scale at eye-level and turn adjustment screw until the internal indicator is precisely aligned with the top zero line
Measure: Create a loop in the end of the rope you want to measure tension in; attach spring scale to loop. Hold the spring scale steady and read off the tension measurement.
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Groups of 2
Develop 2 systems to lift a filled soda bottle 10cm with
1 pulley
2 pulleys
Build your systems
Measure the distance the soda bottle moves and compare it to the distance you had to pull
What is the actual mechanical advantage?
Measure the force you must exert on the string and compare it to the force that is finally transmitted to the soda bottle
What is the ideal mechanical advantage?
Calculate the efficiency of each system
Pulleys & ForceYour Turn
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Now join with one other group at your table
Develop 2 different systems to lift a filled soda bottle 10cm with all 4 pulleys
Build both systems
What are their actual mechanical advantages? Ideal?
Which one has a better efficiency? Why do think that is?
Pulleys & ForceYour Turn
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+Pulleys & Force
Which system required the least amount of force to lift the bottle? How did this system rank in its mechanical advantage?
Do you think the size of the pulley makes a difference in the ideal mechanical advantage? Actual?
How could you further increase the efficiency of your most efficient pulley system design?
What other engineering problems were solved with pulleys or pulley systems?
Conclusion
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End of Saturday Exercises
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TISP: UruguaySunday, 10 May 2009
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Structural engineering and how to reinforce the design of a structure to hold more weight.
Exercise 4:
Critical Load
+Critical Load
Learn about civil engineering and the testing of building structure
Learn about efficiency ratings and critical load
Learn about teamwork and the engineering problem solving
Objectives
43
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Millau Viaduct
Millau, France
World’s Tallest Bridge
2460m long434m pylon height270m road height
December, 2004
Critical LoadGreat Structures of the World
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Yokohama Landmark Tower
Yokohama, Japan
Japan’s TallestOffice Building
296m tall70 floors including office and hotel
July, 1993
Critical LoadGreat Structures of the World
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Beijing National Stadium – “Bird’s Nest”
World’s Largest Steel Structure
258,000 square meters
5 years to construct
110,000 tons of steel used in construction
3,000,000 cubic meters
Opened June, 2008
Critical LoadGreat Structures of the World
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Crystal Cathedral
Garden Grove,California, USA
World’s Largest Glass Building
12 stories tall12,000+ panes of glass
16,000-pipe organ
Opened 1980
Critical LoadGreat Structures of the World
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Skyscraper of Cards
2007 World RecordHouse of Cards
Over 7.5 meters tall
No glue or tape; just cards
Built by Bryan Berg in 2007
Critical LoadGreat Card Structures of the World
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+Bryan Berg at WorkA “cardstacker” from Santa Fe, NM, USA
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Force is placed on a structure
Structure can support up to a certain force created by the weight
At a certain point, the structure will fail, breaking
The maximum force the structure can sustain before failure is known as the “Critical Load”
Critical LoadWhat is Critical Load?
Force
Force
50
+Critical Load
A high critical load is not the only parameter to consider Is the best bridge made by filling a canyon with concrete? It
certainly would have a high critical load!
Consider also the weight of the structure Lighter is better, given the same critical load
These two parameters are combined in an “Efficiency Rating”:
Efficiency
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Groups of 2
Up to 12 cards + 1m tape
Devise a plan to build a load bearing structure Should have a flat top Support load with base area of
10x10cm at least 8 cm above the table
No altering of cards allowed – just tape!
No wrap-ups of tape Tape is used to connect cards only
Critical LoadYour Turn
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Example: Supports load Load is at least 8cm above
table Cards failed after load of
2.4kg Structure made with 4
cards Efficiency rating:
2.4 kg / 4 cards = 0.6 kg/card
Critical LoadYour Turn
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8.5 cmheight
+Critical Load
Your efficiency rating:[Load at Failure] / [# of cards used]
Predict what the rating of your design will be
Build your design
Test it!
Discuss improvements, then repeat exercise for a second design
Your Turn
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+Critical Load
What was your efficiency rating?How close were you to your prediction?
How was your design different from the best design?
How would you change your design? Why?
What other factors would you need to take into consideration if your Card House were a real office building?
Conclusion
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End of Sunday Exercises
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