P10041: TEAK - Sound and Music

Sheryl GillowHeather GodlewskiBryan LozanoJeremy Schuh

Mechanical EngineeringMechanical EngineeringElectrical EngineeringElectrical Engineering

Sponsors: The National Science Foundation WE@RIT

Project Description

TEAK – Traveling Engineering Activity Kits The TEAK project involves the design and

fabrication of 4 hands-on engineering activity kits that relate sound and music to engineering and engineering design

Kits are focused on teaching students in the surrounding Rochester community

Customer Needs

Kits must operate safely in a classroom environment

Kits must relate music and sound to engineering concepts and design

Kits must be portable and durable Kits must be usable by groups of up to 30

students Quick set up and storage Kits must be well documented

Design Concepts

Xylophone Kit Electronic Keyboard Kit Communications Kit Electric Guitar Kit

Xylophone Kit

Xylophone KitKit Description

This kit will allow students to explore the relationship between material properties and the sound produced.

By designing a xylophone utilizing a variety of key materials, key lengths and different mallets, students will hear how the various properties affect the tone and pitch.

Xylophone KitDesign Variables

Key Material Mallets Key Length Key Geometry

Xylophone KitDesign Sketches

Key Geometries Base Concepts

Xylophone KitTesting Methods

Human hearing (how do the sounds differ)

Use an electric tuner

At the end of this activity, students will be able to…

Explain what sound is and how sound waves travel

Explain the difference between tone and pitch

Observe how material properties effect the tone produced

Observe how material geometry can effect the sound produced

Xylophone KitAssociated Risks

Size/weight Cost Activity Time Creating keys that have distinct pitches Parts breaking Parts easily lost Difficult to change out keys Creating a base that can support multiple

geometries

Questions, Concerns, Ideas

Electronic Keyboard Kit

Electronic Keyboard KitKit Description

This kit will offer students the opportunity to build and modify the design of an electronic keyboard, modifying the gain of an inverting amplifier, and the filter type used to modify the tone.

Also, they will be able to test the effects of their design decisions

Electronic Keyboard KitDesign Variables

Gain of Amplifier Frequency Response of Filter

High Pass Low Pass

Electronic Keyboard KitDesign Sketches

Electronic Keyboard KitDesign Sketches

Wein Bridge Oscillator

Electronic Keyboard KitDesign Sketches

Time

0s 0.1ms 0.2ms 0.3ms 0.4ms 0.5ms 0.6ms 0.7ms 0.8ms 0.9ms 1.0msV(U1:OUT)

0V

5V

10V

Electronic Keyboard KitDesign Sketches

Vo = [-(Rf)/(R1=R2=R3)] x [V1+V2+V3]

Summing Amplifier Used to Summate Signals

Electronic Keyboard KitDesign Sketches

Inverting Amplifier

Vo= - Vi x [Rf/Ri]

Student will manipulate ratio of R2 to R1 to control signal level

Electronic Keyboard KitDesign Sketches

High Pass Low Pass

Student can manipulate filter type and cut-off frequency

Electronic Keyboard KitTesting Methods

Human hearing (Is it loud enough?) dB Meter Digital Multi Meter Test Performance

At the end of this activity, students will be able to…

Visualize and understand the propagation of sound waves

Understand the goal and necessity of Amplification

Understand how filtering and frequency content affects tone

Electronic Keyboard KitAssociated Risks

Notes are atonal due to component tolerances

Activity time too short Circuitry not durable enough PCB boarding too expensive or improperly

laid out

Questions, Concerns, Ideas

Communications Kit

Communications KitKit Description

By comparing a mechanical communication device to an electrical one, students will see how there are multiple solutions to the same problem.

They will also get a basic understanding of electromagnetics by building and testing their own speaker and microphone.

Communications KitDesign Variables

Amplifier gain Number of turns in the speaker coil Shape and/or mass of the speaker

At the end of this activity, students will be able to…

Explain what sound is and how sound waves travel

See how a mechanical speaker/microphone system differs from an electrical one

Explain what an electromagnet is and how it can be used to make a speaker

Understand what an amplifier is and why it is used in an electrical system

Understand why a change in resistance creates a change in sound

Communications KitConcept Drawings/Schematics

INPUT outputAmplifier

Image Sources:http://www.clarkzapper.net/breadboard.jpghttp://www.zs6buj.com/MyPics/SDRZero/SDRZero_PCB.jpgClip Art

Communications KitTesting Methods

Human hearing (i.e. is it “loud” enough)

Use a DB meter to measure the difference in volume

Use oscilloscope to view output waveforms

Communications KitRisks

Not enough activity time Speaker output not high enough A homemade speaker may be insufficient

as a microphone The students place the electronic

components in the wrong breadboard locations

Loose wires that cannot be detected

Questions, Concerns, Ideas

Electric Guitar Kit

Electric Guitar KitKit Description

This kit offers the opportunity to design and build one of the most popular instruments in American society. The Electric Guitar is a complex device that integrates several systems demonstrating a great deal of team work. Each kit will focus on the tone contribution of a single string.

Electric Guitar KitDesign Variables

String Diameter and Tension Volume Control

Amplifier Gain Number of windings in pick-up

Tone Control Low Pass Filter “Tone Knob” “Pick Up” placement

Optional inclusion of effects

Basic Electric Guitar

E-Guitar Pickup Effects Amplifier Speaker

Under the strings mounted on the body of the guitar converts mechanical vibration into electric signal

Changes the signal that is coming from the guitar

Signal needs to be amplified to audible volume

Reproduces the signal

Simple Guitar Amplifier

BB

AmpIN

Speaker Box that has an input for the guitar (clear top panel to see the amplifier)

Contains the preamp/amplifier, mounted on it are the speaker, a breadboard, ON-OFF switch, various knobs for adjusting volume, gain, high and low frequencies. Must be battery powered for classroom use.

Push-Pull amplifier to reduce power consumption. (use Class AB output stage)

Electric Guitar KitTesting Methods

Human hearing dB Meter Digital Multi Meter Oscilloscope Electronic Tuner

At the end of this activity, students will be able to…

Visualize and understand the propagation of sound waves and their properties

Understand the goal and necessity of Amplification

Understand how filtering and frequency content affects tone

Electric Guitar KitAssociated Risks

Guitar string fails under tension Activity time too long Output volume too loud Power requirements are too large Mechanical failure of “guitar body”

Questions, Concerns, Ideas

Concept Selection

Selection CriteriaWeight Rating Wtd Rating Wtd Rating Wtd Rating Wtd Rating Wtd Rating Wtd

Functionality

Meets size/weight constraints (portability) 13% 4 0.52 5 0.65 2 0.26 3.00 0.39 4.00 0.52 5 0.65

Can the activity be decomposed into meaningful tasks 10% 4 0.40 3 0.30 3 0.30 4.00 0.40 3.00 0.30 4 0.40

Ease of implementation in any available classroom 13% 5 0.65 5 0.65 4 0.52 5.00 0.65 5.00 0.65 5 0.65

Engineering Points Stressed

Make design decisions 18% 5 0.90 3 0.54 2 0.36 5.00 0.90 2.00 0.36 2 0.36

Observable Differences 13% 5 0.65 4 0.52 3 0.39 4.00 0.52 3.00 0.39 3 0.39

Testing Opportunities 8% 4 0.32 3 0.24 3 0.24 4.00 0.32 2.00 0.16 3 0.24

Solve a problem and draw conclusions 8% 4 0.32 3 0.24 4 0.32 3.00 0.24 3.00 0.24 3 0.24

Demonstrates teamwork 8% 5 0.40 3 0.24 3.5 0.28 4.00 0.32 2.00 0.16 3 0.24

Other

30 minutes of activity time 6% 3 0.18 3 0.18 3 0.18 3.00 0.18 2.00 0.12 3 0.18

Team has skills to create kits 3% 4 0.12 4 0.12 4 0.12 4.00 0.12 4.00 0.12 3.5 0.11

Total Score 4.46 3.68 2.97 4.04 3.02 3.46

Rank 1 3 6 2 5 4

Continue? Yes Yes No Yes Reserve Yes

CONCEPTS

Electric Guitar Push Button Keyboard Sound Booth Xylophone Thumb PianoSpeaker, Mic, Cup

Telephone

Project Risks

Scheduling Allocation of budget Ensuring all kits are engineering oriented

rather than just music oriented Provide adequate engineering analysis to

support proof of concept Ensure selected kit activity is not too

complicated Ensure kits are portable

Work Breakdown Structure

Plan Forward

Product Feasibility Assessment Finalize Engineering Analysis Finalize Technical Drawings and

Schematics Finalize BOM Risk Assessment Prototyping

Questions, Concerns, Ideas