1/18/09 - l7 teamworikcopyright 2009 - joanne degroat, ece, osu1 first design
TRANSCRIPT
1/18/09 - L7 Teamworik Copyright 2009 - Joanne DeGroat, ECE, OSU 1
First Design
1/18/09 - L7 Teamworik Copyright 2009 - Joanne DeGroat, ECE, OSU 2
My First Design Engineers Design When did you first design something? General Guidelines
First Designs In school students encounter situations for
design Science Fairs in highschool Physics and chemistry classes
If not in high school then in college In many programs of study there are class that are
oriented this way. (The freshman program here at OSU has a major design build project)
1/18/09 - L7 Teamworik Copyright 2009 - Joanne DeGroat, ECE, OSU 3
Undergraduate class Several problems to address in an
undergraduate class that I had. How far can a goose fly? How far can a diesel locomotive travel on 1
ounce of diesel fuel? Within the constraints, design a structure that will
support the highest load-to-weight ratio.
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Strength-to-Weight Ratio Size constriants Material constraint
Balsawood Success criteria
Strength to weight ratio
Other constraint No laminating
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Design of Balsa wood structure Assignment set specifications Attempted and did initial testing on a couple
of structures after purchase of balsawood. Then did analysis Thought occurred to me – what is strongest
structure? Construction – I beams Highest moment of inertial structural members I beams and channel beams.
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The resulting structure
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Used a buttress on the I beam where the angled channel beams meet
The resulting structure
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Final Design Used an I beam in the vertical structure with the
side toward the load a little thicker to avoid crushing.
Top and bottom and angled members were channel beams.
Were allowed up to 4 inches wide but used only 2 inches for total weight.
A 12 oz structure ended up supporting 240 pounds before failure.
Strength to weight ratio = 320
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Another design Wanted a skateboard – couldn’t afford one. Has an old pair of clamp-on skates that were too
small. My cousin and I took them apart so you had the
front wheel truck and the rear wheel truck from each.
We bolted these onto a piece of wood to make two skateboards which we were able to use for several years…… (and several bump and bruises)
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The assignment MY FIRST DESIGN
Choose something that you designed in your lifetime.
Write up the design experience. SECTIONS The motivation – why you did it The specification – what was it supposed to do The initial ideas for the design implementation The final implementation The success/failure of the implementation
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