Transcript Goodwin_Stark - International Technology and Engineering

STEM Integration
With Principles of Engineering
International Technology Education Association
Thursday - March 18, 2010
Charlotte, N.C.
Case Study: Auto Safety
Presenters: Chuck Goodwin & Jan Stark
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STE M
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Principles of Engineering
Developed Case Studies
• Auto Safety
• Structures - Survival Shelter
• Energy - Solar Electric Vehicle
Design & or Solar Efficient Home
• Machine Automation and Control
• Ergonomics & Communications
Technology
• Designing Technology For People
with Disabilities
Role of the Teacher
Instructor - Facilitator - Task Master
• Set Guidelines
• Establish the Premise
• Identify Constraints & Schedule
• Guide Students Through Process
• Research Expectations
• Brainstorming
• Team Structures and Dynamics
• Journaling
• Assign Knowledge Building Labs/Experiments
• Ongoing Assessments - Scoring Rubrics
• Student Developed Tests of Design Features
• Final Test of Vehicle Performance - Analysis of outcomes
• Oral Presentation of Team Findings and Related Data.
Automobile Design Variables
• Vehicle Weight
• Engine / Power plant
Type
• Aerodynamics
• Cargo Capacity
• Passenger Capacity
• Fuel Economy
• Ease of Maintenance
• Vehicle Range in Miles
• Visibility - Ergonomics
• Body Strength
• Options Available
Six Engineering Concepts
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Design
Systems
Optimization
Modeling
Ethics
Technology Society Integration
Engineering Habits of Mind
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Systems Thinking
Creativity
Optimism
Collaboration
Communication
Ethical
Considerations
• Critical and analytical thinking,
• Accepting feedback and
learning from mistakes,
• Perseverance with difficult or
ambiguous tasks
• Drawing inferences and
reaching conclusions based on
an evaluation of sources and
their
• Supporting opinions with logical
arguments
EPIC - “Pre-Engineering and Applied
Science Project”, 2007
The Status and Nature of K-12 Engineering Education in the
United States, by Linda Katehi, Greg Pearson, and Michael Feder.
The Bridge-Linking Engineering and Society - 2009
Ideation
How to Arrive at Ideas
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Brainstorming
Attribute Listing
Matrix Checklist
Synectics
Nominal Group Technique
The Delphi Technique
Engineering - An Introduction to a Creative Profession,
Beakley, Evans, Keats, pps.354-362, Macmillan, 1986
Norms of Innovation
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Mistakes OK
Recognition
Rewards
Mutual Respect
Open Communication
Freedom to Experiment
Challenge the Status Quo
Equal Partners
Winning Through Innovation - Harvard Business
School Press, Boston, Mass, 1997
I dentify
Need o r
Pro blem
Redesig n
Res ea rch
Need o r
Pro blem
Co mmunica te
T he
So lutio n
Engineering Design Process
Dev elo p
Po s sible
So lutio ns
T es t
And
E v a lua te
So lutio n
Co nstruct
A
Pro to ty pe
Select
T he B es t
So lutio n
Conceptual Blockbusting
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Perceptual Blocks
Cultural and Environmental Blocks
Emotional Blocks
Intellectual and Expressive Blocks
Alternate Thinking Languages
Conceptual Blockbusting - A Guide To Better Ideas,
4th Ed., by James L. Adams, Basic Books, 2001
Object - Devise as many ways as possible to get the ping pong ball
out of the pipe without damaging the ball, pipe or floor.
Cultural &
Environmental Blocks
6 people in Room
Found Items include:
100’ Clothesline
4”
Metal
Ping
Pong
Ball
Claw Hammer
Pipe
Chisel
Box of Wheaties
File
Wire Coat Hanger
Pipe Wrench
Concrete
Pipe is .06” larger
in dia than the
1.50” Ping Pong
Ball
Floor
Light bulb
Conceptual Blockbusting - A Guide To Better Ideas,
4th Ed. by James L. Adams, Basic Books, 2001
Sub Systems Designed into a
Transportation System
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Chassis
Steering
Suspension
Entertainment
Restraint and Safety
Power Train
Hybrid System
Fuel
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Electrical Harness
Fuse System
Temperature Control
Navigation (GPS)
OnStar
System Monitoring
Engine or Motor
Cooling
• Recyclable ID
• Braking
• Windshield washer
Car Fuse System Model
Control
Adjust
INPUT
Design a fuse
system that
protects all
incorporated
electrical circuits
& devices.
PROCESS
Identify all fuseable
circuits. Connect
fuses in series and
incorporate into an
optimal/easy access
fuse box. Assign
proper amp ratings &
fuse types as per
circuit requirements..
Feedback
Human detection, Circuit
functions properly or
fuses fail - indicating a
problem. Computer
diagnostics & alarm.
OUTPUT
All circuits are
adequately
protected and
operate normally.
Fuses fail at safe
current levels.
System Model
Control
Adjust
INPUT
Maintain a
cabin or
interior Temp.
of 70 degs.F
PROCESS
OUTPUT
Set heat or air
conditioning
controls to
desired
comfort levels.
Desired Temp.
or comfort
level is
achieved
Feedback
Human, Instrument
Computer,,,, etc…
Temperature Control System
NHTSA - IIHS
Crash Safety
• Subaru – 6 Models with 5 star ratings
(frontal and side impacts)
• Volvo – 5 Models with 5 star ratings
(frontal and side impacts)
• Ford Explorer / Ford Taurus / BMW
5 Star ratings (frontal & side impacts)
• Suzuki Equator 4 Star Frontal
1 Star Side impact.
Basic Chassis
Seat Design
Ramp To Wall Excursion
3'
10' 6"
The Wall
Video Recording
& Tim ing
6'
Alternate Approach
Wall
Sand Bag
Car
Pulleys
Whoa …Izzz THAT
A WAAALLL Up Ahead!!
Integrating Green Into Automobiles
• Increase fuel efficiency via new
approaches
• Decrease weight via composites, etc.
• Integrate Hybrid Systems
Fuel Cells-Battery Electric-Propane
• Design with Recyclable Plastics In Mind
• Design with Biodegradable Materials
• Enhance Metal Recovery for Reuse
• Refurbursh and Rebuild Parts.
Recycling Auto Parts
Car Seats
Upholstery
ReUsed GlassArtifical Sand Asphalt Landscaping
90% of
Metals,
Plastics and
Textiles can
be recycled.
Electronics
90% of
Alum.
Gets
Recycled
Battery Polypropelene
Case
Lead reuseAcid reuse
Recycled
Bumpers
Carpets
Recycled Steel
is used to
Manuf.13 Million
new vehicles/Yr.
Oil + Filter
Recycle
Alternators Water Pumps
Windshield
Motors
Retread - Planters Rubberized ‘Roads
Crash Model Body Assembly
Springs Shock Absorbers
Foam or Hard Rubber
Honey Comb Cells
Body Flex
Body Reverse
Engineered
Egg Protection
Passive & Active
3D Modeled
Vacuum
Formed
Crumple Zone
Wall
Multiple Metal
Plates can be
reused
Rush
Carriage Can be used
multiple times
Recyclable
Polystyrene or
Polypropelene
Dashboard Design & System Integration
Research and Observe Current Features
Gee Whiz Exercise - Incorporate New Features/Systems
Build in Ergonomic Considerations
Build in Environmentally Friendly Features
Speed Conversion
5280 ft/mi divided by 3600 sec./ hr = 1.47
ft/sec/mph
1 MPH = 1.47 feet per second
Traveling at 30 mph = how many feet / second?
30 mph x 1.47 ft/sec/mph = 44.1 Ft/Sec
Greater distance than your typical home is long.
68 mph x 1.47 ft/sec/mph =
99.96 ft/sec
Equivalent to 1/3 of a football field
Speed = Distance / Time
Speed is how fast an object is moving without
reference to direction.
Velocity is how fast an object is moving while
knowing its direction of travel.
SPEED
=
Distance
Time
=
300 feet =
60 ft/sec
5 secs
5280 Ft/mi = 1.47 ft/Sec. = 1mph
60 Ft/Sec
= 40.82mph
3600 Secs./Hr.
1.47Ft/Sec/mph
Acceleration Due To Gravity
Acceleration due to G = 9.8 m/s2
1s - 9.8m/s
An Object falling for 3 seconds = has a Vel. of
29.4 m/s.
An object falling for 7 seconds has a Vel. of
68.6 m/s.
2s -19.6m/s
3s - 29.4m/s
What is Terminal Velocity?
7s - 68.6m/s
Car Crash Collisions
Number of Collisions
In a Car Crash
• Collision 1 - When the Car collides with another car or
object.
• Collision 2 - When our bodies are thrown in the
direction of force and collide with the car’s interior +
seat belts & air bags.
• Collision 3 - Body organs (brain, intestines, etc. collide
with our cranium and skeletal frame.
• Collision 4 - Impact with loose objects located within
the car (pets, boxes, books, groceries, etc..)
Metric to English
English to Metric
Mass vs Weight
I pound
= .4536 Kg’s
1 Pound
= .0311 Slugs
I Kg
= 2.205 lbs
1 Slug
= 32.174 lbs
1 Slug
= 14.6 kg & 143 N
1Kg
= 9.802 Newtons
1 Newton
= .102 Kg’s
1 Newton
= .225 Lbs
1 pound
= 4.448 Newtons
Metric to English
English to Metric
Linear Distances & Speed
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Feet
Meters
Yard
Meter
Miles
Mile
Km
50kph
65 mph
= .0348 Meters
= 3.281 Feet
= .9144 Meters
= 1.09 Yards
= 1.61km
= 5280 ft = 1760 Yds = 1614.68m
= .6214 miles
= 31.1 mph
= 104.65 kph
Momentum
Momentum ( P ) = Mass x Velocity
Impetus, impelling force or strength of a physical
object in motion.
P=mxv
Mass = 910 Kg
Vel = 70 m/sec
P = 910kg x 70m/sec = 63,700 kg-m/s
P = 5.3 kg x 25.92 ft/sec = 137.376 kg-m/s
Impulse
Impulse (I) is the product of the applied
force and the time for which it is applied.
Impulse (I) = Fave x change in time (∆t)
Impulse (I) = Change in Momentum
I=Fx
∆t
or
I = F x ∆t
I = 1000 N x 2 secs = 2000 N-secs (Higher)
I = 1000 N x .2 secs = 200 N-secs (Lower)
Airbags Deploy
.015ms to .025ms
Accident Duration
125 ms or 1/8 sec.
F ∆t = ∆Pmom
Reducing Impulse
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Applying Brakes
Crumple Zone Collapse
Air Bag Deployment (Frontal & Side)
Padded and/or Crumple Dashboard
Safety Glass
Seat Belts
Collapsible Steering Column
Seat Padding
Head Rest/Restraint
Newton’s Second Law
Force = Mass x Acceleration
F = ma
Mass = 11.65 lbs
= 5.3 Kg
2.2lbs/Kg
2
2
F = 5.3 kg x 9.81 m/s = 52 kg m/s
2
1 kg m/s = 1 Newton - hence 52 Newtons = 52 Apples
Coefficient of Friction
• Static Friction
µs = F/N
• Kinetic Friction
µk = F/N
• Rolling Friction
µR = F/N
Coefficient of Friction
Force of Friction
80N
Applied Force
155 N
Normal Force
µs =
98N =
155N
.63
Calculating Reaction Time
d = 1/2 gt
t
2
= 2d
t = 2 x 1.5 ft
g
t = 2 x 1 ft
32 ft/sec
32 ft/sec
=
2
0.25 secs.
=
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.306 s
Potential Velocity
of Crash Vehicle
Velocity = 2g∆H
g = 32ft/sec
2
∆H = Ramp = 10.5 ft.
2
Velocity = 2 x 32ft/sec x 10.5 ft
2
Velocity = 672 ft / sec 2
Velocity = 25.92 ft/sec
Velocity = 25.92 ft/sec / 1.47 ft/sec/mph =
17.633 mph
Scaled Velocity of Model Vehicle
Total Linear Distance from Ramp Top to Wall = 20 feet
Time to cover that distance = 1.82 Secs
Model Scale: ½” = 1 foot or 12 inches= 24 Scaled ft/foot
Scaled Distance = 20 ft x 24 scaled ft /1ft = 480 scaled ft
480 scaled ft divided by 1.82 secs = 263 Scaled ft/sec
263 scaled feet/sec divided by 1.47 ft/sec/mph = 178.91mph
3'
10' 6"
The Wall
Video Recording
& Tim ing
6'
Work and Power
Work = Force x Distance = Foot - Pounds
Work = Force x Distance = Newton - Meters
Power = Work / time = Foot - Pounds Or N - M Or
Second
Sec
Joules
Sec
Horsepower
The ability of a horse to lift up a weight of 550
pounds to a height of one foot in one second.
1 H.P. = 746 Watts
OR 746 N-m
Sec
1 H.P. = 746 Joules / Second
1 H.P. = 550 ft-lbs
Sec
Potential and Kinetic Energy
Of Your Crash Vehicle
PE = mgh or Weight x Height
PE = 11.65 lbs x 10.5 feet (Ramp Ht)
PE = 122.33 ft. lbs or 166.21 N-M
1 Slug x 32.2 ft/sec2 = 32.2 lbs
11.65 lbs divided by 32.2 lbs/slug = .362 Slugs
KE = 1/2 mV
2
2
KE = 1/2 x .362 slugs x (25.92 ft/sec )
KE = 121.60 ft lbs or 165.38 N-M
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Egg Weight
Model Car Wt.
Average Human Weight
Average Car Weight
Egg Weight
Average Human Weight
Model Weight
Average Car Weight
1 lb = 454 grams
3lbs = 1362 grams
66.6 g / 1362 g = 1 /20 ratio
170 lbs / 3357 lbs = 1 / 19.75 ratio
Ratios
How Many Revs.
do your tires
turn during the
Crash Test?
Circumference =
1.75”
πD
Diam in Feet = .146 Feet
Circum. = .146 ft x 3.14 = .4587 Feet = 1 Rev.
Linear Distance to Wall Incl Ramp = 14’ + 6’ = 20 feet
20 feet divided by .4587 ft / Rev =
43.6 Revs
Revolutions the Wheels
Turn per Second
Time for the car to travel to the Wall = 1.82 secs
Number of completed Revs from Ramp to Wall = 43.6 Revs
Number of Revs / Sec = 43.6 Revs divided by 1.82 secs =
23.96 Revs per Second
RPM’s = 23.96 Revs / Sec x 60 Sec./Min = 1438 RPM’s
Number of Rads / Sec = 6.28 Rads/Rev x 23.96 Revs/sec.
= 150.47 Rads / Sec
Radians
A Radian is the radius of a circle placed
along the circle’s perimeter or circumference.
Radian
There are 6.28 Radians in the circumference
of a circle.
Moment of Inertia for
Your Wheels/Tires?
Moment of Inertia (I) is a measure of an object's
resistance to changes in its rotation rate.
I = 1/2 mass x radius
2
Mass of one Wheel = 30.2 grams = .302 kgs
I = 1/2 x .302kg x (.022250 m)
2
2
I = 1/2 x .302kg x .000495m
2
I = .00007475 kgm x 4 wheels =
2
.000299 kgm
Angular KE
Angular KE = 1/2 Moment of Inertia x Angular Speed
Angular KE = 1/2 I x W
2
2
Angular KE = 1/2 .00007475 kgm x (150.47 Rads / Sec.)
2
2
2
Angular KE = .846216 Kgm / sec = .846216 N-M or Joule
Angular KE for 4 Wheels = 3.385 N-M
Collision Course!!
A 3500 lb car covers 115 feet in one second find the
following:
Speed in mph
78.23 mph
Speed in Meters/sec
35.1 m/sec
Speed in kph
130.38 kph
Pmom in English
12,581SlugFt/Sec
Mass of car in kg
1590.91 kg
Pmom in metric
55,840.9 kg-m/sec
Collision Course!!
If the same 3500 lb car plunges into a stationary wall at 45 mph
and the total crash is over in 3/32’s of a sec find:
The Force of the Crash
78,152.64 lbs
The Impulse of the crash
7236.81 lb-secs
If the driver of this car weighs 185 lbs find the following:
The Force of the driver
4078 lbs
The Driver’s Impulse
382.35 lb-sec
The Driver’s Momentum
382.35 SlugFt/sec
Auto Safety
Culminating Steps & Expectations
Completed Drawings
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Preliminary and Operational Sketches
Application & Accuracy of Scale Drawings
Coverage of All Essential Design Features
Level of Detail
Appropriate Dimensioning
Combination of CAD Drawing Types Used
How Presented / Displayed For Review
Auto Safety
Culminating Steps & Expectations
Vehicle Design - Constuction - Performance Assessment
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Physical Model Matches Final Drawings
Pre-Crash Performance (Speed - Stability - Momentum)
Overall Crash Performance of Vehicle
Egg Passenger Protection
Crumple Zone Performance
Integration of Appropriate Materials
Design Innovations
Team Work Coordination
Data Comparison Between Model and An Actual Automobile
Final Performance Data - From Crash Video
Compare Actual Performance to Predicted Performance.
Auto Safety
Culminating Steps & Expectations
Oral Report
Powerpoint Presentation
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The Design Problem Introduction
Design Solution Rationale
Team Member Coordination - Contribution
Presentation Outline
Discussion of Problem History & Transition
Mathematical Predictions and Expected Performance
Testing and Analysis Conducted - Resultant Findings - Changes Made
Engagement and Understanding of Audience
Report Conclusion
Fielding Questions and Answers
Auto Safety
Culminating Steps & Expectations
Design Problem Portfolio
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Binder Format and Appearance
Title Page - Sub Titles - Table of Contents
Portfolio Indexing
Brainstorming Problem Results
Design Sketches and Engineering Drawings
Mathematical Solutions and Predictions
Evidence of Research
Engineering Daily Log
Testing and Analysis Methods and Results
Photographic Record of Critical Phases
Activity Sheets
Related Laboratories Completed
Summative Report - Conclusions Drawn From Experience .
Resources/Questions
• [email protected]•
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http://www.globalspec.com
http://www.athenus.com/
http://www.engineeringtalk.com/
http://www.dogpile.com/
• http://www.asee.org/
Chuck Goodwin
Engineering Search Engine
Engineering Search Engine
Engineering Talk
Helpful Search Engine
Amer. Soc. Of Engr. Education
• http://www.safercar.gov/
• http://www.nhtsa.dot.gov/
Natl.Highway Traffic Safety Admin.
• http://www.iihs.org/
Insurance Inst. For Highway Safety
• http://www.crashtest.com/
Crash Tests of All Models
NYSED Curriculum Guides
• http://www.emsc.nysed.gov/cte/technology/pub/home.html