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CHAPTER 1: THE PROBLEM AND ITS BACKGROUND
This chapter presents the background of the study, its conceptual framework, the
problem and its significance, and the scope and delimitation of the study.
1.1 Introduction
Weather has been important to man even from the beginning. Many
significant weather events have affected mankind over the years. This is because
weather affects a wide range of man’s activities, including agriculture,
transportation and even leisure time.
Scientists have worked to develop meteorological sensors since the 1950s.
Modern technology has allowed the combination of several sensors into one
integrated weather station. In order to gather this measured data, manual
observation and recording of data is still employed which is highly error prone.
Using an automated version of this weather station to measure the rain level,
wind speed and direction is paramount to minimize equipment servicing and costs.
It can not only increase the reliability of measuring and recording data but can also
improve the timely availability of data.
1
1.2 Conceptual Framework
This study aims to design and construct an Automated Weather Monitoring System
to make weather monitoring easier. Figure 1 shows the conceptual framework of the
study.
The microcontroller continuously measure weather data that is then stored to the data
logger. Measured weather data is also accessible in a database management system
installed in a computer connected to the microcontroller via serial connection.
1.3 Statement of the Problem
This study aimed to design and construct an Automated Weather Monitoring
System. In doing this, the study had the following specific objectives:
a) To design and construct a computer-based, sensor-operated rain gauge,
anemometer and wind vane that can measure weather data accurately.
2
DATA LOGGER
ARDUINO MEGA
Figure 1. Conceptual Framework of AWMS
b) To create a computer application capable of updating its weather database, and also
display the real time measured data.
c) To store the measured data in a data-logger so as to enable the user to fetch data
whenever a complete log is required.
1.4 Significance of the Study
The large utility of automated weather monitoring in varied areas ranging from
agricultural growth and development to industrial development takes much
significance of conducting this study.
The weather conditions of a field can be monitored from a distant place by farmers
not needing them to be physical present in the area for them to know its climatic
condition. To cite for an example, it would be of great use in the war affected regions as
it would be too risky for farmers to visit their farm regularly as it would enable them to
monitor their farm from their home. Another is for weather observers to easily assess
the weather.
1.5 Scope and Delimitation
This study is delimited to the design and construction of a computer based
weather station that can simultaneously receive and store data.
Furthermore, it would conclude with the testing of functional prototypes and
the determination of the conditions necessary for the device to be economically
feasible.
3
1.6 Definition of Terms
Terms here are conceptually and operationally defined for better understanding of
the readers.
Aerovane – It is used to measure both wind direction and speed. The tail orients the
instrument into the wind for direction while the propellers measure the wind speed.
An anemometer or windmeter is a device used for measuring wind speed, and is a
common weather station instrument. The term is derived from the Greek word
anemos, meaning wind, and is used to describe any air speed measurement
instrument used in meteorology or aerodynamics.
DBMS- Database management systems (DBMSs) are specially designed software
applications that interact with the user, other applications, and the database itself to
capture and analyze data.
Precipitation - In meteorology, precipitation is any product of the condensation
of atmospheric water vapor that falls under gravity.
Rain Gauge - A rain gauge (also known as an udometer, pluviometer, or
an ombrometer) is a type of instrument used by meteorologists and hydrologists to
gather and measure the amount of liquid precipitation over a set period of time
4
CHAPTER 2: REVIEW OF RELATED LITERATURE AND STUDIES
In this review of previous studies and related literature, information is presented in
support of and in anticipation of the methodology and analyses presented in this study.
2.1 Weather
Weather is the state of the atmosphere, to the degree that it is hot or cold, wet or dry, calm or stormy, clear or cloudy.1 Weather, seen from an anthropological perspective, is something all humans in the world constantly experience through their senses, at least while being outside. There are socially and scientifically constructed understandings of what weather is, what makes it change, what effects it has on humans in different situations etc.2
Therefore weather is something people often communicate about. Today, the winds
and other weather variables are of equal concern and can have an even greater impact on
our modern, high-tech life style. Weather affects a wide range of man’s activities, including
agriculture, transportation and leisure time. Often the affects involve the movement of
gases and particulates through the atmosphere.
2.2 Weather Monitoring
To keep a continuous track of the various atmospheric factors which constitute weather at a
place is called weather monitoring.
2.2.1 History
Sensing the winds and weather has been important to man over the centuries.
Athenians built the eight sided Tower of the Winds in the first century B.C. in honour of the
1 Merriam-Webster Dictionary2 Crate, Susan A and Mark Nuttall (eds.) (2009). Anthropology and Climate Change: From Encounters to Actions. Walnut Creek , CA: Left Coast Press. pp. 70–86
5
eight gods of the winds. The Tower of the Winds stands to this day in the ancient agora, or
market, in Athens.3
Many significant weather events have affected mankind over the years. We know of
these because their effects have become part of history. Since much of history is a
recollection of a series of wars and battles,it is interesting to note that a well-known early
reference to the importance of the weather is from the Chinese philosopher Sun Tsu, who
said, “Know yourself and know your enemy, and victory is guaranteed. Know the terrain
and know the weather, and you will have total victory.” Much later in history, we know that
Napoleon’s invasion of Russia in 1812 was stymied when snow and cold weather came
earlier in the season than he and his generals had planned. This, combined with Russian
militia attacks, helped defeat the French, who invaded with 50,000 troops, and left with
only 20,000 survivors. One hundred thirty years later, this was repeated when Hitler’s
invasion of the Soviet Union was again foiled in part by brutally cold winter weather.
In the 20th century, large population migrations were brought about by adverse
weather conditions, including those of the Dust Bowl in the United States during the 1930s,
multiple Asian droughts throughout the century, and three significant periods of drought in
the sahel region of Africa. Individual events that killed and affected many people include
the great smog event in London in 1952, which killed 4,000 people in five days in
December, hurricane impacts on the coasts of the United States, from Galveston in 1900 to
Katrina, Rita and Wilma last year, and several notable blizzards.4
3 Encyclopedia Of Ancient Greece (ed. by Nigel Guy Wilson). Routledge (UK), 2006. ISBN 0-415-97334-1. Pages 214, 2154 Knutson, Thomas R. and Robert E. Tuleya (2004). Journal of Climate 17 (18): 3477–94
6
Man’s effect upon the environment has also been seen in the weather, in more
recent events, when the release of radioactive particles from the reactor accident at
Chernobyl, Ukraine, was detected by sensors outside of the Soviet Union, and traced back
to Chernobyl using sophisticated weather sensors and meteorological models. In a similar
fashion, local weather instruments were used to help estimate the impact of smoke and
soot from oil well fires set during the 1991 Gulf War.5
2.2.2 Present Day Monitoring Techniques
Modern weather monitoring systems and networks are designed to make the
measurements necessary to track these movements in a cost effective manner. This
requires that the total life-cycle cost of a monitoring system is minimized, and one way to
do this is to minimize or eliminate the maintenance of the weather monitoring system.
Using a solid-state system to measure the weather, including the wind speed and direction,
is paramount to minimize equipment servicing and costs.
The conventional weather monitoring system consisted of individual sensors to
measure one meteorological variable, each connected to a data collection device or
recorder. Modern technology has allowed the combination of several sensors into one
integrated weather station that can be permanently located at one site, or transported to a
site where localized weather is needed.
Scientists have worked to develop solidstate meteorological sensors since the
1950s. The first of these were sonic anemometers, which measure the time required for a
sound wave to travel from point A to point B. This time is affected by the speed of the wind
in a predictable and repeatable way. The earliest sonic anemometers were used to measure
5 Ibid p. 6
7
the small scale fluctuations of the winds caused by atmospheric turbulence. The earliest
sensors were not very stable and needed a great deal of maintenance to keep them
operating. Thus, since the turbulence is measured by subtracting a running mean value
from the data to determine the fluctuations, and since the means were unreliable, this was
a perfect use of this instrument. It is only in the past 10 to 15 years that the electronics
have become suitable for use in an instrument that is used for long term measurements of
the winds.
There have been other types of instruments developed to measure the winds
without moving parts. One of these is a thermal anemometer – an instrument that
measures the temperature of a small element in the sensor, and calculates the wind by
measuring the amount of energy carried away from the anemometer. These are often called
hot wire or hot film anemometers. Significant drawbacks of these sensors are that they are
very prone to contamination by dirt, and it is difficult to distinguish energy carried away by
the wind from cooling caused by the impact of raindrops and snowflakes. Another
technique used to measure the winds is to measure the vortices caused by a fixed shape
that is projected into the wind. These vortex shedding anemometers operate on the
principle that when a fluid flows around an obstruction in the flow stream, vortices are
shed from alternating sides of the obstruction in a repeating and continuous fashion. The
frequency at which the shedding alternates is proportional to the velocity of the flowing
fluid. Sensors downstream of the obstruction sense the presence of the Sensors
downstream of the obstruction sense the presence of the vortices and derive the wind
speed from them. These work well in pipes and ducts, but have not been successfully
implemented in the ambient environment.
8
2.2.3 Review of Weather Monitoring Techniques
A. Weather Monitoring by Satellite
The weather satellite is a type of satellite that is primarily used to monitor the
weather and climate of the earth. Satellites can be polar orbiting, covering the entire Earth
asynchronously, or geostationary, covering over the same spot on the equator.
The first weather satellite, Vanguard 2, was launched on February 17, 1959. It was
designed to measure cloud cover and resistance, but a poor axis of rotation kept it from
collecting a notable amount of useful data.
Meteorological satellites see more than clouds and cloud systems. City lights, fires, effects
of pollution, auroras, sand and dust storms, snow cover, ice mapping, boundaries of ocean
currents, energy flows, etc., and other types of environmental information are collected
using weather satellites. Weather satellite images helped in monitoring the volcanic ash
cloud from Mount St. Helens and activity from other volcanoes such as Mount Etna. Smoke
from fires in the western United States such as Colorado and Utah have also been
monitored.
Other environmental satellites can detect changes in the Earth's vegetation, sea
state, ocean color, and ice fields. For example, the 2002 Prestige oil spill off the northwest
coast of Spain was watched carefully by the European ENVISAT, which, though not a
weather satellite, flies an instrument (ASAR) which can see changes in the sea surface.
9
The first weather satellite to be considered a success was TIROS-1, launched by NASA on
April 1, 1960. TIROS operated for 78 days and proved to be much more successful than
Vanguard 2. TIROS paved the way for the Nimbus program, whose technology and findings
are the heritage of most of the Earth-observing satellites NASA and NOAA have launched
since then.
B. Weather Monitoring by Radar
Radar is used to take large scale weather imagery. Radar images allow
meteorologists to see up-to-the-minute weather observations of weather formations like
cloud systems, storm cells and hurricanes. Radar imagery is particularly useful in times of
emergency weather conditions as it provides live coverage of the weather, enabling more
accurate warning systems to be put in place.
Meteorologists use radar to monitor precipitation. It has become the primary tool
for short-term weather forecasting and watching for severe weather such as
thunderstorms, tornadoes, winter storms, precipitation types, etc. Geologists use
specialized ground-penetrating radars to map the composition of Earth's crust.
C. Weather monitoring by microcontroller
Computers play an integral role in modern weather monitoring, enabling more
accurate readings and record keeping.
Computers are usually used in conjunction with weather software and externally
introduced weather readings from satellites, radar readings or from computerized weather
instruments like modern anemometers and thermometers. Computers are used to display,
analyze, record and also predict weather patterns.
10
Computers using weather monitoring software and devices are also often linked to
control mechanisms, so that, for instance, when the temperature reaches a minimum level,
the computer switches on the heating in a house. (Windmill, 2004)
D. Weather Monitoring by Using Simple instruments
For centuries simple technology has been used to monitor weather changes. Basic
instruments like a weather vane or anemometer are used to measure wind speed and
direction---they are stillsome of the most widely used weather monitoring technologies
today. Thermometers, hygrometers, barometers and rain gauges are the basic tools of
monitoring weather, without which the more advanced technologies involved in weather
monitoring and prediction would be useless.
E. Wireless Zigbee Based Weather Monitoring system
In an industry during certain hazards is will be very difficult to monitor the parameter
through wires and analog devices such as transducers. To overcome this problem we use
wireless device to monitor the parameters so that we can take certain steps even in worst
case. Few years back the use of wireless device was very less, but due the rapid
development in technology, now-a-days, we use maximum of our data transfer through
wireless like Wi-Fi, Bluetooth, Wi-Max, etc. A wireless weather monitoring system which
enables to monitor the weather parameter in an industry or anywhere, can also be
designed by using Zigbee technology. The parameters can be displayed on the PC’s screen.
The system contains two parts. One is transmitter node and another one is receiver part
and both can be any number. The transmitter part consists of whether sensors,
microcontroller and Zigbee and the receiver part consist of a PC interfaced with Zigbee
11
through PC serial port. The system monitors temperature, wind speed, wind direction and
humidity with the help of respective sensors. The data from the sensors are collected by
the micro controller and transmitted to the receiver section through wireless medium.
2.3 The Aerovane
An aerovane is used to measure both wind direction and speed. The tail orients the
instrument into the wind for direction while the propellers measure the wind speed. An
aerovane indicates both the wind direction and wind speed or simply the wind velocity. It
is shaped like an airplane. The nose of the plane points to the direction from which the
wind blows and the rotation of the propeller measures the wind speed. The propeller shaft
is coupled to a small dynamo which generates current. The amount of current generated
depends on the rate of rotation of the propeller which depends on the speed of the wind.
The generated current activates a dial which gives a reading equivalent to the wind seed. 6
2.3.1 Estimation of wind
In the absence of equipment for measuring wind, the observations must be made by
estimation. The errors in observations made in this way maybe large, but, provided that the
observations are used with caution, the method may be justified as providing data that
would otherwise not be available in any way. If either temporarily or permanently the wind
data of some stations are obtained by estimation instead of measurement, this fact should
be documented in station records made accessible to data users.
2.3.2 Wind Speed and Direction
6 Common Weather Terms. National Weather Service- National Oceanic and Atmospheric Administration.
12
Wind speed describes how fast the air is moving past a certain point. This may be an
averaged over a given unit of time, such as miles per hour, or an instantaneous speed,
which is reported as a peak wind speed, wind gust or squall. Wind direction describes the
direction on a compass from which the wind emanates, for instance, from the North or
from the West.
Wind speed and direction are important for monitoring and predicting weather
patterns and global climate. Wind speed and direction have numerous impacts on surface
water. These parameters affect rates of evaporation, mixing of surface waters, and the
development of seiches and storm surges. Each of these processes has dramatic effects on
water quality and water level.
Wind speed is typically reported in miles per hour, knots, or meters per second. One
mile per hour is equal to 0.45 meters per second, and 0.87 knots.
Wind direction is typically reported in degrees, and describes the direction from
which the wind emanates. A direction of 0 degrees is due North on a compass, and 180
degrees is due South. A direction of 270 degrees would indicate a wind blowing in from the
west.
The measurement of wind speed is usually done using a cup or propeller
anemometer, which is an instrument with three cups or propellers on a vertical axis. The
force of the wind causes the cups or propellers to spin. The spinning rate is proportional to
the wind speed Wind direction is measured by a wind vane that aligns itself with the
direction of the wind.
2.4 The Rain Gauge
A rain gauge is an instrument used by meteorologists and hydrologists to
measure precipitation in a certain amount of time. It usually measures in millimeters. Rain
gauge is a meteorological instrument for determining the depth of precipitation (usually in
mm) that occurs over a unit area (usually one meter squared) and thus measuring rainfall
13
amount. One millimeter of measured precipitation is the equivalent of one liter of rainfall
per meter squared.
2.4.1 Principles of Measurement
Most rain gauges generally measure the precipitation in millimeters equivalent to
liters per square meter. The level of rainfall is sometimes reported as inches or
centimeters.
Rain gauge amounts are read either manually or by automated weather
station(AWS). The frequency of readings will depend on the requirements of the collection
agency. Some countries will supplement the paid weather observer with a network of
volunteers to obtain precipitation data (and other types of weather) for sparsely populated
areas.
In most cases the precipitation is not retained, however some stations do submit
rainfall (and snowfall) for testing, which is done to obtain levels of pollutants. Rain gauges
have their limitations. Attempting to collect rain data in a hurricane can be nearly
impossible and unreliable (even if the equipment survives) due to wind extremes. Also,
rain gauges only indicate rainfall in a localized area. For virtually any gauge, drops will stick
to the sides or funnel of the collecting device, such that amounts are very slightly
underestimated, and those of .01 inches or .25 mm may be recorded as a trace.
14
Another problem encountered is when the temperature is close to or below
freezing. Rain may fall on the funnel and ice or snow may collect in the gauge and not
permit any subsequent rain to pass through.
Rain gauges should be placed in an open area where there are no obstacles, such as
buildings or trees, to block the rain. This is also to prevent the water collected on the roofs
of buildings or the leaves of trees from dripping into the rain gauge after a rain, resulting in
inaccurate readings.
2.4.2 Types of Rain Gauge
Types of rain gauges include graduated cylinders, weighing gauges, tipping bucket
gauges, and simple buried pit collectors. Each type has its advantages and disadvantages
for collecting rain data.
A. Standard Rain Gauge
The standard NWS rain gauge, developed at the start of the 20th century,
consists of a funnel emptying into a graduated cylinder, 2 cm in diameter, which fits
inside a larger container which is 20 cm in diameter and 50 cm tall. If the rainwater
overflows the graduated inner cylinder, the larger outer container will catch it.
When measurements are taken, the height of the water in the small graduated
cylinder is measured, and the excess overflow in the large container is carefully
poured into another graduated cylinder and measured to give the total rainfall. In
locations using the metric system, the cylinder is usually marked in mm and will
measure up to 250 millimetres (9.8 in) of rainfall. Each horizontal line on the
cylinder is 0.5 millimetres (0.02 in). In areas using Imperial units each horizontal
line represents 0.01 inch.
15
B. Weighing Precipitation Gauge
A weighing-type precipitation gauge consists of a storage bin, which is
weighed to record the mass. Certain models measure the mass using a pen on a
rotating drum, or by using a vibrating wire attached to a data logger. The
advantages of this type of gauge over tipping buckets are that it does not
underestimate intense rain, and it can measure other forms of precipitation,
including rain, hail and snow. These gauges are, however, more expensive and
require more maintenance than tipping bucket gauges.
The weighing-type recording gauge may also contain a device to measure the
quantity of chemicals contained in the location's atmosphere. This is extremely
helpful for scientists studying the effects of greenhouse gases released into the
atmosphere and their effects on the levels of the acid rain. Some Automated Surface
Observing System (ASOS) units use an automated weighing gauge called the AWPAG
(All Weather Precipitation Accumulation Gauge).
C. Tipping Bucket Rain Gauge
The tipping bucket rain gauge consists of a funnel that collects and channels
the precipitation into a small seesaw-like container. After a pre-set amount of
precipitation falls, the lever tips, dumping the collected water and sending an
electrical signal. An old-style recording device may consist of a pen mounted on an
arm attached to a geared wheel that moves once with each signal sent from the
collector. In this design, the wheel turns the pen arm moves either up or down
leaving a trace on the graph and at the same time making a loud click. Each jump of
the arm is sometimes referred to as a 'click' in reference to the noise. The chart is
measured in 10 minute periods (vertical lines) and 0.4 mm (0.015 in) (horizontal
lines) and rotates once every 24 hours and is powered by a clockwork motor that
must be manually wound.
The tipping bucket rain gauge is not as accurate as the standard rain gauge
because the rainfall may stop before the lever has tipped. When the next period of
rain begins it may take no more than one or two drops to tip the lever. This would
16
then indicate that pre-set amount has fallen when in fact only a fraction of that
amount has actually fallen. Tipping buckets also tend to underestimate the amount
of rainfall, particularly in snowfall and heavy rainfall events. The advantage of the
tipping bucket rain gauge is that the character of the rain (light, medium, or heavy)
may be easily obtained. Rainfall character is decided by the total amount of rain that
has fallen in a set period (usually 1 hour) and by counting the number of 'clicks' in a
10 minute period the observer can decide the character of the rain. Correction
algorithms can be applied to the data as an accepted method of correcting the data
for high level rainfall intensity amounts.
Modern tipping rain gauges consist of a plastic collector balanced over a pivot.
When it tips, it actuates a switch (such as a reed switch) which is then electronically
recorded or transmitted to a remote collection station.
Tipping gauges can also incorporate weighing gauges. In these gauges, a
strain gauge is fixed to the collection bucket so that the exact rainfall can be read at
any moment. Each time the collector tips, the strain gauge (weight sensor) is re-
zeroed to null out any drift.
To measure the water equivalent of frozen precipitation, a tipping bucket
may be heated to melt any ice and snow that is caught in its funnel. Without a
heating mechanism, the funnel often becomes clogged during a frozen precipitation
event, and thus no precipitation can be measured. Many Automated Surface
Observing System (ASOS) units use heated tipping buckets to measure precipitation.
D. Optical Rain Gauge
These have a row of collection funnels. In an enclosed space below each is a laser
diode and a photo transistor detector. When enough water is collected to make a
single drop, it drops from the bottom, falling into the laser beam path. The sensor is
set at right angles to the laser so that enough light is scattered to be detected as a
sudden flash of light. The flashes from these photo detectors are then read and
transmitted or recorded.
17
E. Acoustic Rain Gauge
The acoustic disdrometer developed by Stijn de Jong is an acoustic rain
gauge. Also referred to as a hydrophone, it is able to sense the sound signatures for
each drop size as rain strikes a water surface within the gauge. Since each sound
signature is unique, it is possible to invert the underwater sound field to estimate
the drop-size distribution within the rain. Selected moments of the drop-size
distribution yield rainfall rate, rainfall accumulation, and other rainfall properties.
CHAPTER 3: PROJECT METHODOLOGY
3.1 Overview
This chapter outlines and reinforces the procedures necessary to fulfill the
objectives of this study.
The following are to be established in this chapter:
1) Describe the research methodology of the study.
2) Explain sufficiently each method to be employed (i.e., the schematic diagram,
materials used etc.)
3) Demonstrate the procedure used in the design, construction and collection of
data(i.e., testing and calibrating the output/prototype)
3.2 Project Management
Project Management describes the activities involved in organizing and managing
the overall project, and especially the stage of the implementation that the project is
currently in.
18
An illustration of the primary tasks that comprise this chapter follows. These tasks
are the steps that the proponents have used to ensure a timely and cost effective
implementation.
3.3 Strategy and Planning
This stage is concerned with organizing and structuring a ‘road-map’ for
implementation and developing a step-by-step approach to guide the team through the
completion of the project.
3.3.1 Problem Definition
In order to complete this stage of planning, one must first consider all the specific
objectives and scope of the project. Specifically, the objectives of the study are as follows:
a) To design and construct a computer-based, sensor-operated rain gauge,
anemometer and wind vane that can measure weather data accurately.
b) To create a computer application capable of updating its weather database, and also
display the real time measured data.
c) To store the measured data in a data-logger so as to enable the user to fetch data
whenever a complete log is required.
19
Figure 3.1
This project would conclude with the testing of functional prototypes and the
determination of the conditions necessary for the device to be economically feasible.
3.4 Project Design
The Analysis and Design stage is a process of diagraming the hardware and software
requirements of the project according to the desired features. The objective of this stage is
to develop and test a methodology that best suits all the requirements.
Aside from the reliability of the system design, the availability of materials and its
cost efficiency should also be considered.
For the prototypes, the proponents have made use of reed switches for
measurement of weather data. As for the microcontroller, they have used a gizDuino X
(Arduino Mega clone) which is capable to process the measurement and storing of data.
The data logging shield used in this project is an Adafruit pre-assembled data logging shield
with real time clock.
3.4.1 Automated Rain Gauge (ARG)
One of the most essential components of a weather station is the rain gauge. The
proponents have employed a Tipping Bucket Rain Gauge.
Hardware and Software Requirements
1. Precipitation Measurement
By using a tipping bucket rain gauge, rainwater level measurement would be
more convenient but not less reliable. The rain water will fall on the tilted tipping
buckets through a Teflon-coated funnel. The water will fill the bucket facing the
20
funnel opening. The bucket is calibrated to hold up to 0.1 inch of rainwater and will
tilt over as it reaches its limit. The water will be tilted over, while the other bucket
will be positioned facing the funnel opening. This will collect the new rain water.
Each time the bucket is tilted around the magnetic relay it will generate a
pulse. These pulses are counted in a microcontroller-based circuit to measure the
rainfall.
2. External Structure
The external structure of the device is highly critical to
provide accurate measurements. If the methods
previously stated are to be employed, the casing or the
exterior of the device should be compatible with the
electronic devices to be installed so that the total
functionality of the device is not compromised.
The proponents have used a 20 cm-diameter rain gauge.
Each tilt of the rain gauge is calibrated to 0.5 mm or 0.02
inches of water. Each bucket is positioned to collect 0.9739 cubic inches or 15.96 mL
of rainwater.
3.4.2 Automated Windmeter (AWM)
The measurement of wind speed is one of the most important factors in
weather prediction. Wind is the movement of air caused by uneven heating of the
earth’s surface. It occurs in light breezes that are locally generated due to heating of
21
Figure 3.1 Parts of the rain gauge.
an immediate landmass, to winds on a grand scale spanning continents caused by
solar heating.
Besides being used as part of a weather monitoring station there are many
other situations where measurement and knowledge of the wind condition helps in
decision-making such as pollution control, safety of tall structures, control of wind
turbines, studies on the effects of wind on crops, maneuvering of ships and aircraft
landing systems.
The AWM consists of an automated wind vane and an automated
anemometer.
Hardware and Software Requirements
1. The Wind Vane
The wind vane, wind direction dial (magnetic compass), the composition,
wind direction and show value to determine the location of the pointer by the
wind in the wind direction dial.
For the prototype, eight (8) reed switches are positioned as the directions
North (N), Northeast (NE), East (E), Southeast (SE), South, Southwest (SW), West
(W), and Northwest (NW). There is a magnet moving with the wind around these
switches as to close the loop at the corresponding direction. This is processed by
the microcontroller and is stored in the datalogger and is then sent to the
computer via serial communication.
2. The Anemometer
22
Using the traditional tricyclic rotating frame and a reed switch, the
microcontroller in the instrument sample to calculate the wind speed by
counting the number of revolutions over time. This number of revolution can be
translated to distance by computing for the circumference or angular distance
covered.
The specifications of the Automated Windmeter are as follows:
Anemometer Measuring range 0.00 to 20 m/s
Starting speed 0.56 m/s
Wind Vane Measuring Range 0 to 360 degrees, 16 position
Wind Direction given North Automatic
3.4.3 Microcontroller
The proponents have used an Arduino compatible controller, the gizDuino X
It is based on an ATMEGA1281 MCU, a family member of the ATMEGA1280 used in
Arduino Mega board. It offers 54 I/Os, 1 hardware SPI, 2- hardware UART with memory
capacities of 128K FLASH, 8K SRAM, and 4K EEPROM. Other hardware peripherals
additions inherited from ATMEGA1281 chip includes 3 additional timers, 10 additional
PWMs.
3.5 Materials
23
After defining the problem, considering the project objectives, sketching the
project design, the proponents are down to getting the materials needed for the
implementation of the design and hence the completion of the project.
Demonstrated in Table 1 is the list of materials used for the construction of the
device with their specifications.
Table 1
Materials Used for the Construction of the AWMS
Quantity Unit Specification
1 Piece gizDuino X
1 Piece Adafruit Assembled Data Logging Shield
10 Pieces Reed Switch
20 Pieces 6” Male-Male Jumper Wires
20 Pieces 6” Male-Female Jumper Wires
20 Pieces 6” Male-Female Jumper Wires
1 Piece Ogawa Seiki (OSK) Tipping Bucket Type Rain Gauge
1 Piece Anemometer
1 Piece Wind Vane
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Figure 3.4 Reed switch: The reed switch is an electrical switch operated by an applied magnetic field
Pictures of Wind Vane, Anemometer and Rain Gauge
CHAPTER 4: PRESENTATION AND INTERPRETATION OF DATA
CHAPTER 5: SUMMARY OF FINDINGS, CONCLUSION AND RECOMMENDATION
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