Announcements

1

Announcements

Have Quiz sheet ready. Title = QUIZ 7»Name (L, F, MI), »Today’s date 10/2/12, »Lab day , time» section number

Lab Day/Time Section Number

Monday, 1:00 8

Monday, 3:00 9

Wed., 1:00 10

Wed, 3:00 11

Friday, 1:00 12

Lab Day/Time Section Number

Mon. 1:00 8

Mon. 3:00 9

Wed. 1:00 10

Wed. 3:00 11

Thu. 2:00 29

Fri. 1:00 12

Lab Day/Time Section Number

Mon. 1:00 8

Mon. 3:00 9

Tue. 2:00 36

Wed. 1:00 10Wed. 3:00 11Thu. 2:00 35Fri. 1:00 12

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Announcements

First professional memo due next week in lecture.

The preliminary design report is due at the beginning of your Week 10 lab

The final design report is due at the beginning of your Week 13 lab

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Scores on Canvas

Keep all scored work. If a score on Canvas does not match your

records, bring your copy to your GTA or to me (Dr. Roppel in Broun 214) and request a correction. (If I am not in the office, leave it with the ECE secretary and put a note on it.)

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REMINDER

Homework is INDIVIDUAL. You can share content (data, pictures, etc.),

but the writing must be YOUR OWN.

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Announcements

Format and grading rubric for the Design Reports are on the class website:»Format is on main page»Rubric is in the syllabus.

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Announcements

Each TEAM bring the following to lab this week:» Motor control board» transmitter/receiver» Eight (8) AA batteries if needed» Motors are not needed in lab this week

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Lego Car Project

Wirelessly driven Lego car Left and right channels/motors for steering Channels 2 and 3. Goal is to navigate and finish course as

quickly as possible Penalty of 1 second for each 0.5 V over

10V in voltage regulator output

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Lego Car Overview

Receiver

R1, R2

PPM

PWM

PWM

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START/FINISH

BLOCK

Required Gates

Optional Gates(+5 sec. penalty if missed)

Push block across finish line or incur a +30 sec. penalty

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Penalties

Penalties are a way to introduce “cost” into the design and cause the team to make tradeoff decisions.» Incurring a penalty should not be considered unethical or “wrong” in any

sense. 5 second penalty for missing a gate 30 second penalty if the block is not pushed across the finish line Penalty of 1 second for each 0.5 V over 10V in voltage regulator

output (Vo)» Vo ≤10.0V = no penalty» 10.0V < Vo ≤10.5V = 1 second penalty» 10.5V < Vo ≤11.0V = 2 second penalty» etc.

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Competition Grading

Fastest time = 100 pts.» Fastest time ever was 7 sec.

30 seconds = 75 pts.

Other times linearly interpolated between fastest time and 30 sec.

Maximum time allowed is 60 seconds

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Preliminary Design Report Describe design decisions

» Output voltage» Power supply» Wheel size/gears, etc.

Justify your decisions. Explain any disadvantages, and why you’ll

tolerate them. Include supporting drawings, figures, and

tables if needed.

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Lego Car Design Output voltage

» Higher output voltage increases speed» Penalties apply above 10V

Power supply (batteries)» One 9V battery (light, but less than 10V)» Two 9V batteries (≥10V, but heavy)» Watch batteries (very light, but drain quickly)

Wheel size and gears» Torque vs. speed tradeoff

Drive strategy» Front wheel vs. rear wheel drive

Course path» Passing through all gates vs. missing gates» Pushing block vs. not pushing block

Body» Light vs. heavy

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Engineering Reports Report organization Writing style Professional tone Figures and tables

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Engineering Reports Report organization Writing style Professional tone Figures and tables

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Engineering Report Organization

1) Title / cover page2) abstract or executive summary3) front matter (TOC, LOA, LOF, ACK)4) introduction5) technical sections6) conclusions7) references 8) appendices

Items in red are pertinent for your design reports in this course.

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Title Page

Title (unique, but not too long) Names Section and Team Number Name of class/instructor Term (Fall 2012) Date Auburn University

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Example Reports

(shown on doc cam)

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Executive Summary or Abstract

Abstract – typically 100-200 words summarize main conclusions of report In a longer engineering report, an abstract

or executive summary can be up to one page long but never longer.

Audience: your manager, so he/she can read it in 5 min. on the way to board meeting.

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Front Matter

Table of contents Lists of figures, list of tables figures,

acronyms Nomenclature (symbols & abbreviations) Acknowledgements (for funding, editorial

help, encouragement, etc.) Usually use lowercase roman numerals for

page numbers

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Introduction

Problem statement Background (history, relevant information) Summarize approach Outline remainder of report

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Technical Sections

Choice of present design» discuss each tradeoff– six minimum as shown

on next slide.» What alternatives were considered?» Give data supporting your choice» Use Pugh charts–clearly indicate best choice» Explain choice in words

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Lego Car Design Tradeoffs Output voltage

» Higher output voltage increases speed» Penalties apply above 10V

Power supply (batteries)» One 9V battery (light, but less than 10V)» Two 9V batteries (≥10V, but heavy)» Watch batteries (very light, but drain quickly)

Wheel size and gears» Torque vs. speed tradeoff

Drive strategy» Front / rear wheel drive – controllability vs. stability

Course path» Passing through all gates vs. missing gates (time penalty)» Pushing block vs. not pushing block (time penalty)

Body» Light vs. heavy – speed vs. ability to push block

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Technical Sections

Include figures and tables near relevant body text.» Long lists or tables should be referred to an

appendix.» Figures & tables must have captions and be

referenced in the body text. Specifications/drawings/parts/cost

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Technical Sections

Performance (Final Design Report Only)» Predicted» Actual» Explain any differences

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Conclusions

What was accomplished & learned» technical information obtained» NOT information learned about life, school,

etc. (Keep it technical.)» Resist the urge to proclaim what a wonderful

class / teacher this was

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Appendices

Use for material that few people would read in its entirety» long tables» long calculations» detailed specifications

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Engineering Reports Report organization Writing style Professional tone Figures and tables

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Writing Style Short paragraphs

» Introduce your point (Topic position)» Support your point» Drive your point home (Stress position)

Write like a journalist» Newspapers» Magazines

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Writing Style

Use short sentences.» Poor style:

“In lab, we found that a bridge rectifier generated a slightly faster completion time than a half-wave rectifier, but, taking into consideration the penalty for use of extra parts, we decided to use a half-wave rectifier.”

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Writing Style

» Better style:“In lab experiments, a bridge rectifier generated a

slightly faster completion time than a half-wave rectifier. A half-wave rectifier, however, actually yielded a faster time once the penalty for extra parts was considered.”

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Paragraph Too Long

When the force of sound waves implode tiny bubbles within a liquid at room temperature, the surface of the bubble can reach temperatures at least 25,000 degrees Fahrenheit, more than twice as hot as the surface of the sun, scientists reported this month. The center of such a bubble may be even more astonishingly hot. The scientists, at the University of Illinois, did not speculate just how hot the bubble became, but said they had managed to create a state of matter called plasma inside the bubble. In it, some of the electrons have been stripped off the atoms. "This is the first definitive proof of the existence of a plasma" during this kind of bubble implosion,” said one of the scientists, Dr. Kenneth S. Suslick, a professor of chemistry at Illinois.

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Short ParagraphsWhen the force of sound waves implode tiny bubbles within a liquid at room temperature, the surface of the bubble can reach temperatures at least 25,000 degrees Fahrenheit, more than twice as hot as the surface of the sun, scientists reported this month.

The center of such a bubble may be even more astonishingly hot.

The scientists, at the University of Illinois, did not speculate just how hot the bubble became, but said they had managed to create a state of matter called plasma inside the bubble. In it, some of the electrons have been stripped off the atoms.

"This is the first definitive proof of the existence of a plasma" during this kind of bubble implosion, said one of the scientists, Dr. Kenneth S. Suslick, a professor of chemistry at Illinois.

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Formatting Tips

Bad Example

Try to use lists, bullets, and headers as much as you can. Text that runs together in long, drawn-out paragraphs can be hard to follow. It is also hard to see the main points. Furthermore, it makes it difficult to scan quickly for specific points of interest.

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Exploit lists, bullets, and headers Paragraph format:

» can be hard to follow. » hard to see the main points. » difficult to scan for specific points of interest.

Formatting Tips -- Better Example

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Engineering Reports Report organization Writing style Professional tone Figures and tables

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Professional Tone

Don’t make vague assertions.

“We decided to use 12 gauge wire. The 12 gauge wire is efficient for its size. It will conduct enough electricity and not add too much weight to the car. It also offers

a low amount of resistance.”

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Professional Tone

Less vague:

“We decided to use 12-gauge wire. As seen in Table 3, electrical resistance is proportional to wire gauge. Weight is inversely proportional to wire gauge. 12-

gauge wire provided the best tradeoff between weight and electrical resistance.”

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Professional Tone

A report isn’t a diary or a blog.NO:“We tried a half-wave rectifier at first, but then

we put a capacitor in parallel with the circuit and found that the average speed increased.”

YES:“A capacitor in parallel with a half-wave

rectifier gave the highest average speed.”

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The design project is to build a small vehicle from Legos parts powered by the output of a PC sound card. You will select a waveform to play through the sound card, which will then be amplified by an audio amplifier and delivered to the vehicle.

Separate left and right channels will be available so that steering can be accomplished through the balance control on the PC volume control user interface. Circuits will be designed to convert the audio signals to signals that drive the car motors. The goal is to build a vehicle that can complete a race course in the shortest time possible.

Professional Tone

The report should have a consistent, professional-looking format throughout.

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Professional Tone No handwritten marks anywhere!* No hand-drawn figures, unless of

exceptionally high quality. Addressed as one professional to another,

not student to instructor. Avoid contractions (don’t, can’t, …).*Exceptions may apply.

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Professional Tone Avoid expression of feelings. Just state

facts.NO: “We feel that an 18-gauge wire

provides the best tradeoff…”YES: “Our simulations showed that an

18-gauge wire provides the best tradeoff…”

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Professional Tone

Support all assertions with data if it is available.

Types of data» Simulation results» Experimental measurements

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Example

“A capacitor in parallel with a half-wave rectifier gave the highest average speed.”

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Better

“Table 2 shows the average speed around a 10 m track for several rectifiers. A capacitor in parallel with a half-wave rectifier gave the highest average speed.”

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Engineering Reports Report organization Writing style Professional tone Figures and tables

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Figures and Tables Number each figure or table

» Figure 1, Figure 2, etc.» Table I, Table II, etc.

Give each figure/table a caption» Give basic information about the figure/table» Figure captions go below a figure» Table captions go above a table

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Figures and Tables Refer to the figure/table in the text

» Do not make the reader find the figure/table on his/her own!

In the text:» Describe what the figure/table means or represents.» Describe how the numbers in the figure/table were

generated.» Describe any conclusions you draw from the

figure/table.

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Bad Example

20

25

30

35

40

45

50

10 12 14 16 18 20 22 24 26 28 30

Wire Gauge

Cour

se C

ompl

etio

n Ti

me

(sec

.)

SAMPLE

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Good Example

20

25

30

35

40

45

50

10 12 14 16 18 20 22 24 26 28 30

Wire Gauge

Cour

se C

ompl

etio

n Ti

me

(sec

.)

Figure 1. Simulated course completion times

versus wire gauge.

The effect of wire gauge on the course completion time was studied by simulating the circuit in Appendix A using PSpice. Figure 1 shows the simulated course completion times for wire gauges 10-30. It is concluded that 20 gauge wire results in the fastest completion time because it is the best tradeoff between wire resistance and wire weight.

SAMPLE

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Writing Practice

Let’s rewrite this sentence:

“The 1000 ohm resistor showed that it will work better than the 2000 ohm one would of.”

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QUIZ Prep

Have Quiz sheet ready. Title = QUIZ 7»Name (L, F, MI), »Today’s date 10/2/12, »Lab day , time» section number

Lab Day/Time Section Number

Monday, 1:00 8

Monday, 3:00 9

Wed., 1:00 10

Wed, 3:00 11

Friday, 1:00 12

Lab Day/Time Section Number

Mon. 1:00 8

Mon. 3:00 9

Wed. 1:00 10

Wed. 3:00 11

Thu. 2:00 29

Fri. 1:00 12

Lab Day/Time Section Number

Mon. 1:00 8

Mon. 3:00 9

Tue. 2:00 36

Wed. 1:00 10Wed. 3:00 11Thu. 2:00 35Fri. 1:00 12

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Quiz 7, pg. 1 of 21. The Executive Summary should be placed

immediately after the (a) Title Page

(b) Introduction (c) Table of Contents

2. Design decisions are best presented (a) in a Pugh chart, (b) on a graph.

3.

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Quiz 7 – p.2 of 2

3. Write the letter & underlined part of the best sentence:

(a) We felt that the best value of R2 was 1000 ohms.

(b) Hopefully, 1000 ohms will be a good value for R2.

(c) Performance testing of the car followed by calculation indicates that the best value of R2 is 1000 ohms.