Comprehensive Design Review Team Vibraid March 2014

Vibraid Michael Balanov (Mike) EE Spyridon Baltsavias (Spiros) EE Reona Otsuka (Leo) EE Andrew Woo (Andy) EE

Previous Block Diagram switch signal variable resistance

Revised Block Diagram switch signal 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 Requirements SpecificationValue 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 Requirements SpecificationValue Max detection radius for 50dB-120dB sound within frequency range 3m (10ft), 90% of times Frequency detection range100Hz 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: kHz

FPR Goal - Revised Requirements SpecificationValue Max detection radius for 50dB-120dB sound within frequency range 3m (10ft), 90% of times Frequency detection range100Hz to 10kHz Belt circumference75-105cm (small-large) Belt width<10cm Belt thickness<5cm Product weight<1kg Detection directionality4 directions Vibration response time<o.5sec Vibration directionalityVibration to alert user in one quadrant Vibration to corresponding detection99% of times Tunable sensitivityBlock-all till pass-all Tunable frequency detection4 modes: full range, 100Hz to 4kHz, 4kHz to 7kHz, 7kHz to 10kHz Tunable motor strengthNo 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: kHz 9i j0j1&sourceid=chrome&espv=210&es_sm=122&ie=UTF-8#q=frequency+range+of+alarms

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Gantt chart