Comprehensive Design Review

Team VibraidMarch 2014

VibraidMichael Balanov(Mike) EE

Spyridon Baltsavias(Spiros) EE

Reona Otsuka(Leo) EE

Andrew Woo(Andy) EE

Previous Block Diagram

44

4 4 4 8

switch signal

variable resistance

variable resistance

Revised Block Diagram

44

4 4 4 4

switch signal

variable resistance

variable resistance

Demo Outline

• 4 way directionality amplitude comparison• Microphone inputs, processing and output functioning

correctly.• Filter not yet integrated but functional

FPR Goal - Revised RequirementsSpecification Value

Max detection radius for 50dB-120dB sound within frequency range

3m (10ft) , 90% of times

• How to meet spec?• Amplitude comparison algorithm modifications• Time delay estimation between input sound signals

Determining Time delay

• Use cross-correlation of pair of signals

• Find argmax, corresponding to delay (in samples) between signals

FPR Goal - Revised RequirementsSpecification Value

Max detection radius for 50dB-120dB sound within frequency range

3m (10ft) , 90% of times

Frequency detection range 100Hz to 10kHz

• Sampling frequency?• 10kHz ADC on Arduino• 4 inputs -> 10k/4 = 2.5kHz each• 1.25kHz maximum signal

• Important sound frequencies• Baby cry: 300 – 440 Hz• Car Horn: 400 – 500 Hz• Alarms and sirens: 1 - 3 kHz

FPR Goal - Revised RequirementsSpecification Value

Max detection radius for 50dB-120dB sound within frequency range

3m (10ft) , 90% of times

Frequency detection range 100Hz to 10kHzBelt circumference 75-105cm (small-large)Belt width <10cmBelt thickness <5cmProduct weight <1kgDetection directionality 4 directionsVibration response time <o.5secVibration directionality Vibration to alert user in one quadrantVibration to corresponding detection 99% of timesTunable sensitivity Block-all till pass-allTunable frequency detection 4 modes: full range, 100Hz to 4kHz, 4kHz to 7kHz,

7kHz to 10kHzTunable motor strength No vibration (0V) to Max supply (5V)

Q&A

CDR Deliverables• Goal: Demonstrate 4-way detection and vibration directionality• Correct quadrant determination• Meet range, frequency specs• Implement working user interface• Prototype filter• Implement levels of motor activation • Portable power supply

Pros and Cons of Design

• Pros• Intuitive polar representation• Horizontal orientation• Adjustable

• Cons• User may need to tuck in their shirt• Hand/clothing obstruction

Sprectrum of potential sound sources

• Baby cry: 300 – 440 Hz• Car Horn: 400 – 500 Hz• Alarms and sirens: 1 - 3 kHz

https://www.google.com/search?q=frequency+range+of+alarams&oq=frequency+range+of+alarams&aqs=chrome..69i57.5644j0j1&sourceid=chrome&espv=210&es_sm=122&ie=UTF-8#q=frequency+range+of+alarmshttp://en.wikipedia.org/wiki/Vehicle_hornhttp://www.livescience.com/38298-cry-analyzer-could-indicate-babies-health.html

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Gantt chart