Mathew R. Duguid April 26, 2007 ECET 491 Senior Design Professor Paul Lin Purdue University Fort Wayne, Indiana Project Advisor: Gary Steffen Automated

Mathew R. Duguid

April 26, 2007

ECET 491 Senior Design Professor Paul Lin

Purdue University Fort Wayne, IndianaProject Advisor: Gary Steffen

Automated Piezometer System

Project OverviewProject Overview


Automated monitoring system for piezometers

Marchland Levee in Louisiana Folsom Dam in California

AgendaAgenda


Technical Background

System Design

Testing Procedures and Results

Demonstration

Project BackgroundProject Background


Army Corps of Engineers

● Original Proposal Rejected

Technical Background – PiezometersTechnical Background – Piezometers


What is a piezometer?

A hydrological Instrument used to measure statistics

about groundwater, such as:

Temperature

Pressure (Hydraulic head)

Groundwater flow



Where are piezometers used?

Dams

Levees

Water treatment

Mining Operations

and many more…



Piezometer Installation



Where are piezometers used?

Underground view of piezometer



Methods of monitoring piezometers:

Manual Automated – Wired or Wireless



Current Automated monitoring system problems:

Expensive

High power requirements

Proprietary technologies

Automated Monitoring System DesignAutomated Monitoring System Design


Project goals:

Inexpensive

Low-power and wireless

Easy to install and maintain



Design overview:

Automated Piezometer System high-level overview



Piezometer Sub-system:

Key Technologies

• Tmote Sky MOTE

• PS9800 Pressure Transducer

• HIH-4000



Tmote Sky MOTE:

CNN – “ one of eight technologies that will save the world”



Tmote Sky MOTE:

Sensor Network MOTE

• TI MSP430 Microcontroller• Flash Memory• IEEE 802.15.4(WPAN) Radio



Tmote Sky MOTE:

Uses the TinyOS Operating System

-Delta Application provides:

○ Multihop mesh network○ Sleeping○ Software GIO○ Time synchronization



Tmote Sky MOTE:

12-bit Analog-to-Digital Converter

Water Level Battery Capacity Relative Humidity



PS9800 Submersible Pressure Transducer:

Pressure Transducer

Versus

Vibrating Wire Transducer



PS9800 Water Level Measurement Process:

Current Output

Converted to a Voltage

Converted to an ADC Count

Converted to a Voltage

Converted to a Current

Converted to a pressure

Converted to a Height of Water

18V



Battery Capacity Sensors:

MSP430 internal voltage Sensor



HIH-4000 Humidity Sensor:

Tmote Sky Integrated SHT11

The HIH-4000 was chosen because: • 64 % less power • 1 % more accurate • Not Integrated



Base Station Components:



Delta (base station version)



Delta

Dlisten -C- captures packets from serial- verifies and escapes, strip frame- displays measurements to the screen- submits measurements to database



Delta

PostgreSQL Database

dlisten PostgreSQL



Delta

HTTP Server

dlisten PostgreSQL HTTP Server



Theoretical Resolution:

ADC Water Height Resolution = .1268 inches



Theoretical Accuracy:

Water Level Accuracy = 99.815 %

Battery and Humidity = 0 – 5 %

System TestingSystem Testing


PS9800 Accuracy Test

Complete System Test

Tmote Sky MOTE Power Consumption Analysis



Setup

Protek B845 DMM



PS9800 Accuracy Test 1

Amount of Water Added

(inches)

Sensor Output (milliamps)

Derived Amount of Water(inches)

% Error

1 .0396 1.02 2.798 %

1 1/8 .0443 1.15 2.634 %

1 .0396 1.02 2.798 %

6 3/32 .2413 6.27 2.949 %

6 .2373 6.17 2.799 %

6 .2358 6.13 2.113 %



PS9800 Accuracy Test 2

Test Range

Actual Water Amount (in)

Measured Water Amount (in)

Average Error (in)

ABS Average Error (in)

Average Error (%)

ABS Average Error (%)

1"

1 1.010025549

-0.004 0.016 -0.425% 1.591%1.0625 1.080492448

1 0.9630476171 0.986536583

1.03125 1.033514516

6"

6.03125 6.060153297

-0.005 0.021 -0.089% 0.352%6.09375 6.0601532976.03125 6.036664336.03125 6.036664336.09375 6.060153297

12"

12.15625 12.19077349

-0.027 0.040 -0.218% 0.332%12.1875 12.09681763

12.21875 12.2142624612.03125 11.979372812.28125 12.26124039

TotalAverages -0.0120 0.0259 -0.244% 0.758%



Complete System TestActual9V (V)

Meas.9V (V)

Actual3V (V)

Meas.3V (V)

ActualWL (ft)

Meas.WL (ft)

ActualRH (%)

Meas.RH (%)

14.89 15.02 3.120 2.981 2.675 2.694 47 49

14.89 15.03 3.128 2.982 1.433 1.426 48 51

14.88 15.02 3.129 2.980 1.100 1.109 47 46

14.88 15.02 3.127 2.984 .783 .7821 48 46

14.88 15.03 3.127 2.980 .250 .2519 48 48

9V Error

3V Error

WLError

RHError

Expected 0 – 5% 0 - 5% 0 - 0.5% 1 – 4 %

Actual .87% 4.66% .330 % 2.13%



Tmote Power Consumption Testing



Old Computers!



Tmote Power Consumption Testing

Time (seconds)

Cur

rent

(m

A) DataSheet

RX – 21.8 mATX – 19.5 mA

MCU – 1.8 mASleep – 5.1 uA


Questions?

Documents

Mathew R. Duguid April 26, 2007 ECET 491 Senior Design Professor Paul Lin Purdue University Fort Wayne, Indiana Project Advisor: Gary Steffen Automated