Final Presentation Glass Break Detection Team

Team Members Dennis Narcisse Pic 24 Programming Synapse Programming Matthew Marsh Signal Processing Hardware Implementation PCB Modifications Christian East Opamp Configuration Signal Processing Enclosure Design Mark Lynn Technical Documentation PCB Design Enclosure Design

Advisor Dr. Raymond Winton Advisor MOS Devices, RFIC, and ASIC

 Introduction  Problem Statement  Solution  Constraints  Technical  Practical  SD1 Prototype  SD2 Prototype Improvements  PCB Design  Enclosure Design  Final Product Testing Overview

 Glass Break Detection System (GBDS) is an alarm system that detects the frequency of breaking glass  Consist of a central unit and multiple detection units  System communicates wirelessly among all units Introduction

 Current glass break alarms operate:  as stand alone units  hardwired to a central unit  High cost for complicated designs Problem

 Use low power wireless technology  Central unit communicates to all detection units  Simplified design to lower overall cost Solution

NameDescription RangeThe detection unit must detect glass breaking up to 25 feet. AccuracyThe detection unit must detect the noise frequency emitted by the breaking of glass to prevent false alarms from normal household sounds. Supply VoltageThe detection units must be battery powered. The central unit must be wall powered. Transmission DistanceCentral and detection units must be able to wirelessly communicate within a 33 to 246-ft range. DisplayThe central unit must have a display screen that is easily read. Technical Constraints

Practical Constraints

 Manufacturability  The GBDS must be simple in its design Practical Constraints

Prototyping Design

 Added Pic24FJ64GA002  Added Gain Amplifier after low-pass and high-pass filters.  Added Voltage Comparator SD2 Improvements

 Added the Pic24FJ  Faster wake up time than Synapse  Low power microcontroller  Functions of the Pic24FJ  Interfaced with voltage comparator  Handles ADC conversions  Communicates with Synapse

 High and Low Pass Gain Amplifiers  43 times amplifier for greater accuracy  Amplified Vmax to be easily read by the microcontroller SD2 Improvements

 LM 339N Voltage Comparator  Low power  Compares AC voltage from low-pass filter to a DC reference voltage  Used to wake Pic24FJ

Central Unit

Detection Unit

Detection Unit Schematic

Central Unit Schematic

PCB Boards Central UnitDetection Unit

Central Unit PCB

Detection Unit PCB

 CANTEX Size: 4 x 4 x 2 Junction Box Cost: $4.30/box Size: 6 x 6 x 4 Junction Box Cost: $11.62/box Enclosure

 Central Unit  Precision cut for the LCD screen  Hole punches for buttons  Hole punch for LED Enclosure Modifications

 Detection Unit  Buzzer cuts  Microphone cut Enclosure Modifications

 Microphone Audible Range Final Product Testing Range (ft)Thud Level (V) Glass Level (mV)

 Low Pass Gain Amplifier Final Product Testing

 High Pass Filter Amplifier Final Product Testing

 Changes in Sensing Block Old VoltageNew VoltageOld ADCNew ADC High Pass650 mV340 mV Low Pass1.62 V1.3 V

 Synapse Wireless Transmission Distance  Well above our technical constraint of 250 ft. Final Product Testing

 Battery Life  Calculated 41 months  Current draw during normal operation is 365 uA Final Product Testing

Central UnitDetection Unit Parts$53.14$54.48 PCB$19.00$28.90 Assembly$0 Packaging$11.62$4.30 Final Cost$ Production Cost

Final Product Testing

References

Questions