TISP Demonstrations

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TISP:

What is available to teachers and students

July 2009

Selected Lesson

Plans from the

TISP Library

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TISP:

Shenzhen

July 2009

Moshe Kam

D.G. Gorham

Ship the Chip

Sort It Out

Critical Load

Pulleys and Force

Rotational Equilibrium

Understanding Bar Codes

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Exercise 1:

Ship The

Chip

Package design and the engineering behind shipping products safely

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Ship the Chip

Objectives

Learn about engineering product planning and design

Learn about meeting the needs of the customer and society

Learn about teamwork and cooperation

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Ship the Chip

Students will learn…

Manufacturing Engineering

Package design, manufacture and test

Material properties and selection

Real world application of mathematics

Teamwork

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Ship the Chip

The Challenge

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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Ship the Chip

Procedure

1.

Sketch a design on the worksheet

Label your worksheet with Table # and Team Name

2.

3.

4.

Construct a model of your package

At a test station, drop the package from a height of 1.5 meters

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.

8.

Label your package with Table # and Team Name

Submit your worksheet and package to the Test Team for overnight testing

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Ship the Chip

Materials

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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Ship the Chip

Tools and Accessories

Scissors

Marking pen

Pencils/Pens

Calculator

Rulers

Digital Scale

Clear Adhesive

Tape

Masking Tape

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Ship the Chip

Scoring

Overall

_

Score

10

_ _

_ _

3

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 Chip

Calculating Volume

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 cm 3 below in the prism shown

If your package weighed 100g and had a volume of 800 cm 3 and the chip has arrived broken in 3 pieces:

Overall

_

Score

_ _

_ _

3

Overall

_

Score

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0.3125

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Ship the Chip

Procedure

1.

Sketch a design on the worksheet

Label your worksheet with Table # and Team Name

2.

3.

4.

Construct a model of your package

At a test station, drop the package from a height of 1.5 meters

Open your package and examine the chip

5.

7.

Calculate and record your score

6.

Using a second kit, redesign and construct a new package

Record the second design on the worksheet

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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Exercise 2:

Sort It Out!

The engineering behind industrial sorting processes

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Sort It Out

Objectives

Learn about engineering of systems and about measurements

Learn about sorting mechanisms

Get an introduction to Performance

Indices and measures of errors

Learn about teamwork and cooperation

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Sort It Out

Sorting through History

Miners panning for gold

Quality control in food and other industries

Bottle sorting for recycling

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Sort It Out

Different Types of Sorting

Image Processing for the operation of Casinos

Off-the-shelf cameras, frame grabbers, and imageprocessing software used to develop a casino-coin sorting

Lighting

system

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Frame

Grabber

Digital I/O &

Network

Connection

Camera &

Optics

PC platform

Inspection software

Part Sensor

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Sort It Out

Different 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

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Coin in

Center

Transverse line represents direction of magnetic field

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Sort It Out

Why Coin Sorting is Needed

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

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Sort It Out

Why Coin Sorting is Needed

Mixed coins are

Sorted

Rolled

Re-circulated through banks and businesses

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Sort It Out

Your Turn

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 16 mixed coins into separate containers.

In our experiment we use washers:

½ Inch

1 Inch

1¼ Inch

1½ Inch

You will make TWO designs today

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Sort It Out!

Parallel Sorter

Input

Sorting

Mechanism

½”

1”

1½”

1¼”

Output

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Sort It Out!

Parallel Sorter

Input

Sorting

Mechanism

Output

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Sort It Out!

Serial Sorter

Input

Sorting

Mechanism

Output

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Sort It Out

Performance Index 1: “Distance Index”

How good is it?

1: “Distance” performance index:

1

½ ½

½

½in

1

1

1 1

1in

1

1¼in

1

1½in

Distance from correct bin here,

D error

= 2 bins

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A washer that does not get sorted has maximum

D error

= 3

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Sort It Out

Performance Index 2: “Percentage Index”

How good is it?

2: “Percentage” performance index:

1

½ ½

½

½in

1

1

1 1

1in

1

1¼in

1

1½in

#

of washers incorrectly identified

Total

#

of washers to sort 40

5%

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Sort It Out!

Table Number:

Team Name:

# of this type in each container

1/2":

1/2"

1":

1 1/4":

1 1/2":

Type of Sorter Serial

Container for this size washer:

Parallel

Total washers sorted:

16

1" 1 1/4" 1 1/2"

Number left unsorted:

Distance Index:

Percentage Index:

Sort It Out!

Table Number:

Team Name:

# of this type in each container

1/2":

1/2"

4

1":

1 1/4":

1 1/2":

16

The Perfect Group

Type of Sorter Serial

Container for this size washer:

Parallel

Total washers sorted:

16

1" 1 1/4" 1 1/2"

4

4

4

Number left unsorted:

0

Distance Index:

Percentage Index:

0

0%

Sort It Out!

Distance Performance Index

sqrt( 0x1 2 + 0x2 2 + 0x3 2 ) = 0

A Perfect Score!

Remember: Lower is better

Percentage Performance Index

( 0 / 16 ) x 100 = 0%

Another Perfect Score!

Sort It Out!

Table Number:

Team Name:

# of this type in each container

1/2":

1/2"

4

1":

1 1/4":

1 1/2":

16

Not That Perfect

Type of Sorter Serial

Container for this size washer:

Parallel

Total washers sorted:

16

1" 1 1/4" 1 1/2"

4

1

4

3

Number left unsorted:

0

Distance Index:

1

Percentage Index:

6.25%

Sort It Out!

Distance Performance Index

sqrt( 1x1 2 + 0x2 2 + 0x3 2 ) = 1

A Less Than Perfect Score!

Remember: Lower is better

Percentage Performance Index

( 1 / 16 ) x 100 = 6.25%

A Less Than Perfect Score!

Sort It Out!

Table Number:

Team Name:

# of this type in each container

1/2":

1/2"

1

1":

1 1/4":

1 1/2":

4

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The Truly Miserable

Type of Sorter Serial

Container for this size washer:

Parallel

Total washers sorted:

16

1"

1

4

1 1/4"

1

1 1/2"

1

Number left unsorted:

2

2

Distance Index:

6.16

Percentage Index:

56%

Sort It Out!

1/2":

1":

1 1

4

1 1

Number left unsorted:

2

Distance

Index:

6.16

1 1/4":

4

Percentage

Index:

56%

1 1/2":

2

Distance Performance Index

sqrt( 1x1 2 + 1x2 2 + 4x2 2 + 1x3 2 + 2x3 2 ) = 6.16

Much higher score, much lower performance

Remember: Lower is better

Percentage Performance Index

( 9 / 16 ) x 100 = 56.25%

Again, much lower performance

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Sort It Out

Your Turn

Design (draw) a mechanical sorter that can separate the ½in, 1in,

1¼in, 1½in washers

Input: either

Mechanical “shaking” of your device is allowed as part of its operation

Parallel – all 16 washers are inserted at start of your sorter together; or

Serial – 16 washers are inserted at start of your sorter one at a time

Materials:

glue, tape, paper or plastic plates, cardboard, scissors or hole punch, foil, paper, cardboard tubes washers

Output: Each size of washer in its own physical container or surface

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Sort It Out

Your Turn

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?

You will make TWO designs today: one PARALLEL and one SERIAL

Mechanical “shaking” of your device is allowed as part of its operation

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Sort It Out

Conclusion

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?

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Exercise 3:

Pulleys &

Force

All about force and how pulleys can help reduce it

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Pulleys & Force

Objectives

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

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Pulleys & Force

Basics of Pulleys: Two orientations

Fixed Pulley Movable Pulley

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Pulleys & Force

Basics of Pulleys

Compound Pulley

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

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2 T = 100 N

T = 50 N

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Pulleys & Force

Mechanical Advantage

Mechanical Advantage (MA) is the 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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Pulleys & Force

Work

Work is the amount of energy transferred by a force acting through a distance

Work = Force x

Work =

Force x

Distance

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 & Force

Efficiency

The ratio between Actual and Ideal mechanical advantage is Efficiency

Frictionless system = 100% Efficiency

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Pulleys & Force

Pulleys in the World

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!

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Pulleys & Force

Pulleys in the World

Pulleys are used in elevators to change the direction of the tension in the cable, reduce power required of lift motor

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Pulleys & Force

Pulleys in the World

Industrial cranes lift large loads for construction and transportation

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Pulleys & Force

Measuring 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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Pulleys & Force

Your Turn

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

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Pulleys & Force

Your Turn

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?

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Pulleys & Force

Conclusion

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?

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Spring Scale

www.arborsci.com

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Exercise 4:

Critical

Load

Structural engineering and how to reinforce the design of a structure to hold more weight.

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Critical Load

Objectives

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

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Critical Load

Great Structures of the World

Millau Viaduct

Millau, France

World’s Tallest Bridge

2460m long

434m pylon height

270m road height

December, 2004

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Critical Load

Great Structures of the World

Yokohama Landmark Tower

Yokohama, Japan

Japan’s Tallest

Office Building

296m tall

70 floors including office and hotel

July, 1993

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Critical Load

Great Structures of the World

Beijing National Stadium – “Bird’s

Nest”

World’s Largest Steel Structure

258,000 square meters

5 years to construct

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110,000 tons of steel used in construction

3,000,000 cubic meters

Opened June, 2008

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Critical Load

Great Structures of the World

Crystal Cathedral

Garden Grove,

California, USA

World’s Largest

Glass Building

12 stories tall

12,000+ panes of glass

16,000-pipe organ

Opened 1980

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Critical Load

Great Card Structures of the World

Skyscraper of Cards

2007 World Record

House of Cards

Over 7.5 meters tall

No glue or tape; just cards

Built by Bryan Berg in

2007

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Bryan Berg at Work

A “cardstacker” from Santa Fe, NM,

USA

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Critical Load

What is Critical Load?

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”

Force

Force

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Critical Load

Efficiency

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!

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Consider also the weight of the structure

Lighter is better, given the same critical load

These two parameters are combined in an

“Efficiency Rating”:

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Critical Load

Your Turn

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

10 x

10cm 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

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FREQUENTLY ASKED

QUESTIONS

STRUCTURE NEEDS TO BE CONNECTED

BENDING OF CARDS IS ALLOWED

CUTTING OF CARDS IS NOT ALLWOED

YOU CAN ATTACH SEVERAL CARDS

TOGETHER TO MAKE A THICKER CARD

THE TOP OF THE STRUCTURE SHOULD ALLOW

FOR A LOAD WITH 10X10CM BASE

HEIGHT SHOULD BE AT LEAST 8CM

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Critical Load

Your Turn

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

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8.5 cm height

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Critical Load

Your Turn

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

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Critical Load

Conclusion

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?

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The End

Questions or Comments

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