Senior Design II - Fall 2007 ECE 392 Advisor Dr. Kurt Kosbar ECE 392 Instructor Norman Cox Human Detection and Tracking Using a Wireless Sensor Network ECE 392 Students Joe Bishop Emilio Nanni James Jolly Supporting CS 397 Students Scott Lively, Evan Shaw, Eddie Kotowski

Presentation Flow OverviewRefresher Hardware Objectives Software Objectives Design Sensing Challenges Hardware Design Software Development Summary The Present Budget The Future

Overview: Tracking Scenario

Overview: Applications Intruder Detection Smart Indoor Environments Monitoring Hazardous Environments Covert Surveillance Border Security

Crossbow MICA2 Mote Crossbow MIB600 Ethernet Programming Board Sensor Network Gateway Overview: Available Hardware

Overview: Hardware Objectives Design Sensor Circuit Layout Data Acquistion Board Build Wireless Sensor Unit Enclosure

Berkeley Mote 900 MHz Radio ATmega128L µC PIR Sensor Data Acquisition Board TinyOS Overview: Sensor Unit PIR1 PIR2 PIR3 PIR4PIR5 PIR6 PIR7 PIR8

Overview: Software Objectives Relay PIR Data from Sensor Units to PC Capture Data in Database Track Heading to Human Moving Past Sensor Unit Triangulate Position of a Human Visualize Tracking Task

XServe Middleware PostgreSQL Database Qt Visualization TinyOS Overview: Data Flow

Black Body Radiation Plank’s Law T = 310K = 98.6ºF Humans Emit Infrared Radiation Design: Human Emission Spectra

Balanced Differential (Series Opposed) Dual Element PIR Sensor Sensitive 7-14 μm Viewing Angle 138º - Too Large Focus the Viewing Angle with a Fresnel Lens New Viewing Angle 15º Design: Passive Infrared Sensor

8 PIR Sensor’s in a Circular Pattern with 18º of Separation Two Concentric Rings with PIR Sensor at the Focal Point of the Lens Design: Wireless Sensor Unit Enclosure 4 in 2.9 in 8 in 1.25 in

Sensor Unit Housing

Wireless Sensor Unit

Range of Sensor m Speed of Target m/s Frequency Range Hz Design: PIR Characteristics 15º

Design: Motion-detecting Circuit Appropriate Filtering Appropriate Gain Output in Acceptable Voltage Range Output Needs Symmetric Swing Air Currents –Fresnel Lenses Help

Design: Active Bandpass Filter

f = 3 Hz A = 800 Design: Frequency Response Frequency Gain

Design: Frequency Response Frequency Gain f = 3 Hz A = 30 dB

Design: SDAB Considerations Signal to Noise Ratio (SNR) Power Consumption Interfaces –PIR Sensors –Mote 51-pin Board-to-board Connector Dimensions Layout Cost

Design: SDAB Layout

separate sensor and mote power supplies –mitigates sampling problems caused by battery voltage fluctuations metal enclosure –holds sensors in place, blinds them as necessary –mitigates radio interference problem –mitigates capacitive coupling between boards Design: Hunting Noise Sources

Design: Example PIRSDAB Output samples (approx. 16 per s) ADC output

Design: Interpreting Each Output

Design: Data Capture used PostgreSQL database supports software testing easy to extend stored data

Design: Qt Visualization

Design: Position Estimator

Summary: The Present Hardware Complete Mote Software Complete Qt Visualization Complete Tracking Software Needs Work Demo Next Week!

Summary: Budget Part DescriptionUnit PriceQuantityTotal Price RE200B PIR Sensor PicoBlade 1.25 mm Straight Headers PicoBlade 1.25 mm Receptacles Crimp Terminal AWG Crimp Terminal AWG Hirose Connector Lenses0320 PCB Fabrication Miscallaneous100 Total466.83

Hardware: Gain Adjustments Improved Construction Single Power Supply Software: Custom Middleware Use Baeysian Inference to Interpret PIR Signal Improve Position Estimator Summary: The Future

What a long, strange trip it has been!