Comprehensive Design Review
Team Vibraid
March 2014
Michael Balanov
(Mike) EE
Reona Otsuka
(Leo) EE
Vibraid
Spyridon Baltsavias
(Spiros) EE
Andrew Woo
(Andy) EE
Previous Block Diagram
4
4
4
4
8
4
variable
resistance
switch signal
variable
resistance
Revised Block Diagram
4
4
4
4
4
4
variable
resistance
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
Specification
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 Requirements
•
•
Specification
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 Requirements
Specification
Value
Max detection radius for 50dB-120dB sound within frequency
range
3m (10ft) , 90% of times
Frequency detection range
100Hz to 10kHz
Belt circumference
75-105cm (small-large)
Belt width
<10cm
Belt thickness
<5cm
Product weight
<1kg
Detection directionality
4 directions
Vibration response time
<o.5sec
Vibration directionality
Vibration to alert user in one quadrant
Vibration to corresponding detection
99% of times
Tunable sensitivity
Block-all till pass-all
Tunable frequency detection
4 modes: full range, 100Hz to 4kHz, 4kHz to 7kHz, 7kHz to
10kHz
Tunable 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..6
9i57.5644j0j1&sourceid=chrome&espv=210&es_sm=122&ie=UTF-8#q=frequency+range+of+alarms
http://en.wikipedia.org/wiki/Vehicle_horn
http://www.livescience.com/38298-cry-analyzer-could-indicate-babies-health.html
D
d
Gantt chart