ABSTRACT
The main aim of this project is to utilize the application of the Arduino board to control the intensity of street light. As the traffic decreases slowly during latenight hours, the intensity gets reduced progressively till morning to save energy and so, the street lights switch on at the dusk and then switch off at the dawn, automatically. The process repeats every day. White Light Emitting Diodes (LED) replaces conventional HID lamps in street lighting system to include dimming feature. The intensity is not possible to be controlled by the high intensity discharge (HID) lamp which is generally used in urban street lights. LED lights are the future of lighting, because of their low energy consumption and long life. LED lights are fast replacing conventional lights because intensity control is possible by the pulse width modulation. This proposed system uses an Arduino board and a rectified power supply. String of LED are interfaced to the Arduino board with a MOSFET device. The intensity control of the LED light is possible by varying duty cycle from a DC source. A programmed Arduino board is engaged to provide different intensities at different times of the night using PWM technique. This project is also enhanced by integrating the LDR to follow the switching operation precisely.
CHAPTER 1 INTRODUCTION 1.1 OBJECTIVE OF THE PROJECT
The main consideration in the field of technologies are Automation, Power consumption and cost effectiveness. Automation is intended to reduce man power with the help of intelligent systems, Power saving is the main consideration forever as the source of the power (Thermal, Hydro etc.,) are getting diminished due to various reasons. The main objective of the project is to save s ave electrical energy automatically used in street light by the application of power saving elements such as LDR. We want to save power automatically instead of doing manual, so it’s easy to make cost effe ctiveness. This saved power can be
used in some other applications, such as in irrigation, villages, towns and many other fields. f ields. we can design intelligent systems by using Arduino to control intensity of street lights. The idea of designing a new system for the streetlight by using LED that do not consume huge amount of electricity and illuminate large areas with the highest intensity of light whenever required. Providing street lighting is one of the most important and expensive expenditure of electricity in a city. Lighting can account for f or 30-50% of the total energy bill in typical cities worldwide. Street lighting is a particularly critical concern for public authorities authorities in developing developing countries countries because of its strategic strategic importance for economic and social stability. Inefficient lighting wastes significant financial resources every year, and poor lighting can cause accidents. Use of Energy efficient technologies can reduce cost of the street lighting drastically and also provide excellent efficiency. 1.2 Techniques Used in Arduino
Manual control is prone to errors and leads to energy wastages and manually dimming during midnight is impractical. In this paper two kinds of sensors will be used which are light sensor like LDR and photoelectric sensor. The light sensed will detect darkness to activate the ON/OFF switch, so the streetlights will be ready to turn on and the photoelectric sensor will detect movement to activate the streetlights. LDR, which varies
according to the amount of light falling on its surface, this gives an induction for whether it is a day or night. The photoelectric sensor will be activated only in the night. If any object crosses the photoelectric beam, a particular light will be automatically ON. By using this as a basic principle, the intelligent system can be designed for the perfect usage of streetlights in any place. The lighting system consists of Arduino board, LDR, photoelectric sensor and other electrical equipment’s. By using the LDR we can operate
the lights, i.e. when the light is available then it will be in t he OFF state and when it is dark the light will be in ON state. It means LDR is inversely proportional to light, when the light falls on the LDR it sends the commands to the Arduino board that it should be in the OFF state then it switch OFF the light, the photoelectric sensor will be used to turn ON or OFF the light according to the presence or absence of the object. All these commands are sent to the controller then according to that the device operates. We use a MOSFET switch as a relay to act as an ON/OFF switch. 1.3 HID Lamp
High-intensity discharge lamps (HID lamps) are a type of electrical gas-discharge lamp which produces light by means of an electric arc between tungsten electrodes housed inside a translucent or transparent fused quartz or fused f used alumina arc tube. This tube is filled with noble gas and often also contains suitable metal or metal salts. The noble gas enables the arc's initial strike. Once the arc is started, it heats and evaporates the metallic admixture. Its presence in the arc plasma greatly increases the intensity of visible light produced by the arc for a given power input, as the metals have many emission spectral lines in the visible part of the spectrum. High-intensity discharge lamps are a type of arc lamp. Brand Br and new high-intensity discharge lamps make more visible light per unit of electric power consumed than fluorescent and incandescent lamps, since a greater proportion of their radiation is visible light in contrast to infrared. However, the lumen output of HID lighting can deteriorate by up to 70% over 10,000 burning hours. This lamp is significantly more fragile, and they are not solid state in the same way as LEDs. So we can use LED light.
1.4 Need of the System
The traditional implementation and organization of street lighting have no possibilities for improving improving and development development any more. more. The dynamic changes in economy, economy, energy supplies and ecology on national, Indian and world like scale require an automatic, adequate modernization of street lighting. However, this would be possible only with a quite new functional conception which in fact means flexibility, automation, adaptability of street lighting. Simultaneous ensuring of the conditions of safe traffic and decreasing the energy consumption and operational costs could be realized in conformity with the constantly changing parameters of the environment. In conformity with the 24 hours change of daylight, the highly changeable traffic, the variable meteorological conditions and some extreme situations on the roads, the intensity of street lighting should change in a dynamic manner. 1.5 Operation of LDR Sensor
The device consists of a pair of metal film contacts. Separated by a snakelike track of cadmium sulphide film, designed to provide the maximum possible contact area with the two metal films. The structure is housed in a clear plastic or resin case, to provide free access to external light. Practical LDRs are available in variety of sizes and packages styles, st yles, the most popular size having a face diameter of roughly 10mm. practical LDR is shown in below figure.
Fig 1.1 LDR Sensor Spectral response:
The resistors are only light dependent over a limited range of wavelengths. LDRs have their maximum response at about 680nm. Temperature dependency:
Electrons can be excited not only by photons but also by b y thermal agitation. The dark resistance is therefore not infinite at normal temperatures. It increases with the ambient temperature coefficient is, however, very small and can be neglected. Recovery rate:
When an LDR is brought from a certain illuminating level into total darkness, the resistance does not increase immediately to the dark value. The recovery rate is specified in k ohm/second and for current LDR types it is more than 200k ohm/second. The recovery rate is much greater in the reverse direction, e.g. going from darkness to illumination level of 300 lux, it takes less than 10ms to reach a resistance which corresponds with a light level of 400 lux. LDRs are sensitive, inexpensive, and readily available devices. They have good power and voltage handling capabilities, similar to those of a conventional resistor. Their only significant defect is that they are fairly low acting, taking tens or hundreds of LDR include light and dark-activated switches and alarms, light beam alarms and reflective smoke alarms etc. A LDR may be connected either way round and no special precautions are required when soldering.
Darkness: Maximum resistance, about 1Mohm
Very bright light: Minimum resistance, about 100 ohm.
1.6 Infrared LED
An IR LED, also known as IR transmitter, is a special purpose LED that transmits infrared rays in the range of 760 nm wavelength. Such LEDs are usually made of gallium arsenide or aluminum gallium arsenide. They, along with IR receivers, are commonly used as sensors. It appearance is same as a common LED. Since the human eye cannot see the
infrared radiations, it is not possible for a person to identify whether the IR LED is working or not, unlike a common LED. To overcome this problem, the camera on a cell phone can be used. The camera can show us the IR rays being emanated from the IR LED in a circuit.
Fig 1.2 LED An LED lamp is an electric light or light bulb for use in light fixtures that produces light using light-emitting diodes (LEDs). LED lamps have a lifespan and electrical efficiency which are several times greater than incandescent lamps, and are significantly more efficient than most fluorescent lamps, with some chips able to emit more than 300 lumens per watt (as claimed by Cree and some other LED manufacturers). The LED lamp market is projected to grow by more than twelve-fold over the next decade, from $2 billion in the beginning of 2014 to $25 billion in 2023, a compound annual growth rate (CAGR) of 25%. As of 2016, LEDs use only about 10% of the energy an incandescent lamp requires. Like incandescent lamps and unlike most fluorescent lamps (e.g. tubes and compact fluorescent lamps or CFLs), LEDs come to full brightness without need for a warm-up time; the life of fluorescent lighting is also reduced b y frequent switching on and off. The initial cost of LED is usually higher. Degradation of LED dye and packaging materials reduces light output to some extent over time. Some LED lamps are made to be a directly compatible drop-in replacement for incandescent or fluorescent lamps. An LED lamp packaging may show the lumen output, power consumption in watts, color temperature in kelvins or description (e.g. "warm
white"), operating temperature range, and sometimes the equivalent wattage of an incandescent lamp of similar luminous output.
Fig 1.3 LED Light Bulb Most LEDs do not emit light in all directions, and their directional characteristics affect the design of lamps, although omnidirectional lamps which radiate light over a 360° angle are becoming more common. The light output of single LED is less than that of incandescent and compact fluorescent lamps; in most applications multiple LEDs are used to form a lamp, although high-power versions (see below) are becoming available. LEDs, as their name suggests operate as diodes, and run on DC, whereas mains current is AC and usually at much higher voltage than the LED can accept. Although low voltage LED lamps are available LED lamps can contain a circuit for converting the mains AC into DC at the correct voltage. These circuits contain rectifiers, capacitors and may have other active electronic components, which may or may not permit the lamp to be dimmed. 1.6.1 LED drivers
LED chips require controlled direct current (DC) electrical power and an appropriate circuit as an LED driver is required to convert the alternating current from the power supply to the regulated voltage direct current used by the LEDs. LED drivers are the essential components of LED lamps or luminaries. A good LED driver can guarantee a long life for an LED system and provide additional features such as dimming and control. The LED drivers can be put inside lamp or luminaire, which is called a built-in type, or be
put outside, which is called an independent type. According to different applications, different types of LED drivers need to be applied, for example an outdoor driver for street light, an indoor point driver for a down light, and an indoor linear driver for a panel light. 1.6.2 Thermal management
Compared to other lighting systems LEDs must be kept cool as high temperatures can cause premature failure and reduced light output. Thermal management of high-power LEDs is required to keep the junction temperature close to ambient temperature. LED lamps typically include heat dissipation elements such as heat sinks and cooling fins and very high power lamps for industrial uses are frequently equipped with cooling fans. 1.6.3 Efficiency droop
The term "efficiency droop" refers to the decrease in luminous efficacy of LEDs as the electric current increases above tens of milliamps (mA). Instead of increasing current levels, luminance is usually increased by combining multiple LEDs in one lamp. Solving the problem of efficiency droop would mean that household LED lamps would require fewer LEDs, which would significantly reduce costs. In addition to being less efficient, operating LEDs at higher electric currents creates higher heat levels which compromise the lifetime of the LED. Because of this increased heating at higher currents, high-brightness LEDs have an industry standard of operating at only 350 mA. 350 mA is a good compromise between light output, efficiency, and longevity. Early suspicions were that the LED droop was caused by elevated temperatures. Scientists proved the opposite to be true — that, although the life of the LED would be shortened, elevated temperatures actually
improved the efficiency of the LED. The mechanism causing efficiency droop was identified in 2007 as Auger recombination, which was taken with mixed reaction. In 2013, a study conclusively identified Auger recombination as the cause of efficiency droop. 1.7 PWM Technique
The main objective of the PWM is to control the inverter output voltage and to reduce the harmonic content in the output voltage. The pulse width modulation (PWM) techniques
are mainly used for voltage control. These techniques are most efficient and they control the drives of the switching devices. Pulse-width modulation (PWM), or pulse-duration modulation (PDM), is a modulation technique used to encode a message into a pulsing signal. Although this modulation technique can be used to encode information for transmission, its main use is to allow the control of the power supplied to electrical devices, especially to inertial loads such as motors. In addition, PWM is one of the two principal algorithms used in photovoltaic solar battery chargers, the other being maximum power point tracking. The average value of voltage (and current) fed to the load is controlled by turning the switch between supply and load on and off at a fast rate. The longer the switch is on compared to the off periods, the higher the total power supplied to the load. The PWM switching frequency has to be much higher than what would affect the load (the device that uses the power), which is to say that the resultant waveform perceived by the load must be as smooth as possible. The rate (or frequency) at which the power supply must switch can vary greatly depending on load and application, for example Switching has to be done several times a minute in an electric stove; 120 Hz in a lamp dimmer; between a few kilohertz (kHz) and tens of kHz for a motor drive; and well into the tens or hundreds of kHz in audio amplifiers and computer power supplies. The term duty cycle describes the proportion of 'on' time to the regular interval or 'period' of time; a low duty cycle corresponds to low power, because the power is off for most of the time. Duty cycle is expressed in percent, 100% being fully on. The main advantage of PWM is that power loss in the switching devices is very low. When a switch is off there is practically no current, and when it is on and power is being transferred to the load, there is almost no voltage drop across the switch. Power loss, being the product of voltage and current, is thus in both cases close to zero. PWM also works well with digital controls, which, because of their on/off nature, can easily set the needed duty cycle.
Pulse Width Modulation, or PWM, is a technique for getting analog results with digital means. Digital control is used to create a square wave, a signal switched between on and off. This on-off pattern can simulate voltages in between full on (5 Volts) and off (0 Volts) by changing the portion of the time the signal spends on versus the time that the signal spends off. The duration of "on time" is called the pulse width. To get varying analog values, you change, or modulate, that pulse width. If you repeat this on-off pattern fast enough with an LED for example, the result is as if the signal is a steady voltage between 0 and 5v controlling the brightness of the LED. In the graphic below, the green lines represent a regular time period. This duration or period is the inverse of the PWM frequency. In other words, with Arduino's PWM frequency at about 500Hz, the green lines would measure 2 milliseconds each. A call to analog Write () is on a scale of 0 - 255, such that analog Write (255) requests a 100% duty cycle (always on), and analog Write (127) is a 50% duty cycle (on half the time) for example.
Fig 1.4 Pulse Width Modulation Once you get this example running, grab your Arduino and shake it back and forth. What you are doing here is essentially mapping time across the space. To our eyes, the movement blurs each LED blink into a line. As the LED fades in and out, those little lines will grow and shrink in length. Now you are seeing the pulse width.
CHAPTER 2 LITERATURE SURVEY 2.1 M Popa, C Cepisca. Energy consumption saving solutions based on intelligent street lighting control system. U P B Sci Bull, 73:297-308, 2011.
Energy consumption in the public lighting system represents the largest part of the energy usage of a community, while the maintenance and operation of the system is a considerable expense for every city. The paper focuses on products and innovative components for street lighting, proposing a consumption reducing solution based on an intelligent system for remote measurements and control with dimming technologies for HID lamps. The results indicate that considerable energy savings are achieved and the service life of the lamps is extended. Public lighting systems are a major source of electricity consumption, in present 3.19% of global electricity generation is used for lighting. This amount is greater than production of all hydro or nuclear plants and equals with the production from natural gas. The carbon dioxide produced to generate this electrical energy represents about 70% of global emissions from passenger cars and three times the emissions from aviation. This is the reason why reducing power consumption for street lighting brings benefits on a global scale, not only for individual cities. Street lighting can be defined as the artificial illumination of streets when available natural light drops below a pre-determined level. This public service provides a safer environment to its users, including: facilitation of traffic flow and reduction of night accidents, enhanced sense of The majority of existing public lighting systems still uses obsolete technology - some as old as the 1960’s high pressure mercury lamp systems. By switching to modern and more
efficient systems like the ones utilizing dimming technology, the energy bills can be drastically reduced and carbon emissions minimized. 2.2 Schwab R N, Walton N E, Mounce J M and Rosenbaum M J. Energy efficiency in lighting-considerations and possibilities Volume 2, Chapter 12, Highway Lighting. Report No. FHWA-TS-82233. Federal Highway Administration, 1982.
Energy efficiency is a prime consideration for all lighting professionals with reasons ranging from the threat of climate change through burning fossil fuels to the sustainability and availability of energy supplies as well as rapidly increasing costs. But it must be balanced against the need for well-lit environments to ensure the productivity, well-being, safety and health of the people it serves. A well-lit environment must provide both visual function and visual amenity for the particular application and for the architecture, together with an efficient use of energy. This means considering all the elements that contribute to the design and operation in an all-embracing manner. The challenge now is to address more critically the design, operation and specification of electric lighting in combination with available daylight. This will require new thinking and research to achieve satisfactory, efficient environments that will need investment for optimum results. But the outcome could be a long-term benefit to society with the benefit being greater than the sum of the parts. 2.3 Donald A Cleland. Street light monitoring and control. United States of America Patent US 8,290,710 B2, 16 October 2012.
The project "street light monitoring and control system" is developed for automatic street lights maintenance and to reduce power consumption. The application is designed in such a way that we place light sensors in all street light circuits, which is responsible to switch on and off automatically. once the lights are switched on current sensors placed at every street light circuits are responsible to report problem status to the centralized system with help of GSM module attached with the circuit. The status is available in the centralized system, the work man now can easily locate the particular light to take care which minimizes the time to search it and repair. The system also maintains database to store useful information from each street light like power consumption, total number of burning hours, total number of interruptions, tally the actual power consumption with the power supplied and details of fault detection. Hence maintaining the system with optimal power consumption giving commercial benefits to business and the prosperity of the city as a whole. A well-designed, street lighting system should permit users to travel at night with
good visibility, in safety and comfort, while reducing many malfunctions occurs during night and enhancing the appearance of the neighborhood. Conversely, poorly designed lighting systems can lead to poor visibility which may not be helpful for any pedestrian and who are passing by that street. Quite often, street lighting is poorly designed and inadequately maintained (e.g., there are large numbers of burned-out lamps), and uses obsolete lighting technology, thus consuming large amounts of energy and financial resources. Providing street lighting is one of the most important and expensive responsibilities of a city. Street lighting is a particularly critical concern for public authorities in developing countries because of its strategic importance for economic and social stability. Our proposed plan for street light monitoring and control system can provide street lighting maintenance. This maintenance can also enable municipalities to expand street lighting to additional areas, increasing access of providing street light for all the streets and also other underserved areas. In addition, improvements in lighting quality and expansion in services can improve safety conditions for both vehicle traffic and pedestrians. 2.4 D A Devi and A Kumar. Design and implementation of CPLD based solar power saving system for street lights and automatic traffic controller. International Journal of Scientific and Research Publications, 2(11):1-4, 2012.
Solar energy is one of the major renewable sources and is non polluted. Hence, the utilization of this energy is essential everywhere where the maximum possibility of utilization of solar energy is there. One of such possibility is solar power to street lights and traffic systems. Hence, an attempt is made to implement the solar power saver system for street lights and automatic traffic control unit. The proposed system is implemented with MAX3032 Altera CPLD with 32 macro cells. An infrared sensor array is installed on the streets to know the presence of traffic. As there is a requirement of light only at night times, light detectors are used in the system to work it only in the absence of sun light when there is a presence of traffic. In this way the maximum power can be saved. Proposed cost effective system not only saves the power rather it reduces the usage of conventional
energy. The proposed system logic is implemented using VHDL. The main objective of the present study is to reduce the power consumption and efficient utilization of renewable sources for the application of street lightening and traffic signaling. Hence, this paper is aimed at design and implementation of an automatic system to control the traffic and reduce energy consumption of a town’s public lighting system up to the maximum possible
extent. The density of traffic is sensed by using an array of Passive Infrared Sensors (PIR), which senses the traffic movement. LDR is used to detect the presence of day light. The proposed system is able to control the traffic during the day as well as night. In this system, the streetlights are switched ON/OFF automatically during the presence of the traffic only during the nights. Street lighting provides a safe nighttime environment for all road users including pedestrians. Providing street lighting is one of the most important and expensive responsibilities of a city. Lighting can account for 10 – 38% of the total energy bill in typical cities worldwide. Street lighting is a particularly critical concern for public authorities in developing countries because of its strategic importance for economic and social stability. Inefficient lighting wastes significant financial resources every year, and poor lighting creates unsafe conditions. Energy efficient technologies and design mechanism can reduce cost of the street lighting drastically. 2.5 Divya Guddeti. Design and implement of wireless sensor street light control and monitoring strategy along with GUI. IJITR, 78-81, 2016.
As of late improving the lattice unwavering quality amid the top moment is picked up a great deal of considerations. Also, utilizing renewable vitality frameworks to nourish remote regions which are not wanted to be encouraged from the utility since they are a long way from it is an another objective of numerous scientists. One out of these heaps is the road lighting particularly. In this manner, this paper proposes a standalone sunlight based vitality free framework for road lighting as there is no force requested from the matrix. The proposed framework comprises of a PV board, stockpiling framework, LED light, control molding framework (PCS) and the controller which can deal with the force bearing and framework operation. Utilizing LED as a part of lighting applications has numerous focal
points contrasted with other light. It is extremely proficient (high productivity lighting source) and financially savvy (the life time is long contrast with different lights). In augmentations to, it needs low dc voltage source to be worked. The capacity framework will be charged amid the day time utilizing the accessible daylight. Then again, amid the evening time the controller will give a sign to the framework to associate the LED light to be prepared for use. Subsequent to the LED needs a low dc voltage to be worked, so a basic dc-dc converter will be sufficient for this framework bringing about diminishing the expense of the general framework. Chosen of recreation results have been given to approve the proposed framework. 2.6 V. Dogaru, H. Andrei, C. Cepisca, E. Dogaru, M. Popa, T. Ivanovici, Luminance monitoring and optimization of luminance metering in intelligent road lighting control systems, , ISEE 2002, Proceedings, International Symposium on Electrical Engineering, June 2002, Targovişte, pp.225-231
For energy saving reasons, intelligent road lighting control systems are increasingly used and road surface luminance is one possible input parameter. In this paper the current status of luminance monitoring is reviewed giving emphasis on road surface luminance monitoring. In practice many factors may affect road surface luminance monitoring, e.g., different road surface properties under varying weather conditions, orientation of luminance meters, different measuring heights and distances, disturbances of road profile and vehicles on the road. A series of road surface luminance measurements were conducted and the measuring results were analyzed in order to find out the optimal placement of luminance meters. The paper ends up with recommendations on luminance metering for intelligent road lighting control systems. 2.7 Ahmed Sharique Anees, Anupriya, Ayushy Chowdhary, Shalini Dubey, Shweta Verma. Solar powered led streetlight with automatic intensity control. International Journal of Innovative Research in Electrical, Electronics, Instrumentation and Control Engineering, 3(6):32-36, 2013.
As we all know that energy consumption has increased a lot and sources of energy are limited so in order to meet the increasing demand of energy use of renewable sources of energy is a must. Keeping this in mind in this paper we are discussing about solar led street light with auto intensity control. This street light is driven by solar energy and apart from this it also controls its intensity from dusk to dawn depending upon the brightness. A case study is also done to show advantages of solar led street light compare to that of traditional street light. This street light can save a large amount of electricity compared to the tradition one which are alight to their maximum intensity at all times after they are switched on. The main function of the streetlight is to illuminate the street at dark hours. Earlier, the street lighting was very simple and also accounted for less investment as the number of streets were less. But, with rapid urbanization the number of streets increased rapidly and this led to increase in number of street lights and investment associated with them. For designing a proper street light various factors are to be considered which includes its efficiency to provide proper lighting on the street, its harmful environmental effect, installation and running cost etc. So before designing a street light all these factors should be considered properly and efforts should be made to incorporate technologies which are mosrecost effective like the one we have discussed here “ solar led street light with automatic intensity control”. There are various types of street lights according to the lamp
used such as incandescent light, mercury vapour light, metal halide light, high pressure sodium light, low pressure sodium light, fluorescent light, compact fluorescent light, induction light and LED light. For the past several years high and low pressure sodium lamps have been used for street and security lighting but improved LED technology and their lower prices have the potential to replace them in future. 2.8 Arduino Based Auto Street Light Intensity Controller (PDF Download Available). Availablehttps://www.researchgate.net/publication/316889619_Arduino_Based_Aut o_Street_Light_Intensity_Controller [accessed Mar 13 2018].
This paper demonstrates an easy, tough and energy efficient street light intensity control system which does not need much maintenance. The concept is sensing the
brightness in the surrounding environment and controlling the intensity of street lights accordingly. LDR Sensor is affixed to sense the luminosity in the environment. The system uses Arduino, a MOSFET is used for controlling the intensity of LEDs. A cluster of LEDs acts as a streetlight. The system is more dependable than systems with time slots and requires less perpetuation as compared to other available systems. The 21st century is striving hard to save electrical energy. Street lights are essential, but expensive, therefore there is need to optimize the system in a way that it is affordable and efficiently conserves energy. Manually controlling the street lights is a time taking and tedious process. Working in such manner could sometimes result in large disasters and destructions. The main problem that manual controls on the street lights face is that there would be a lot time taking during evening times when they are to be switched ON and a significant waste of energy is done at morning at all could not be turned OFF together at once. Another way in which the wastage is done is that at midnights lights glow at full intensity although there is not much traffic. Therefore, there is a need to come up with a system which overcomes the problems of existing systems. A system which reduces manual control and would efficiently save energy. This could be done by using low power, robust and efficient components. 2.9 Sharath Patil G S, Rudresh S M, Kallendrachari K, Vani H V. Design and implementation of automatic street light control using sensors and solar panel. International Journal of Engineeing Research and Applications, 5(6):97-100, 2015.
Solar Photovoltaic panel based street lighting systems are becoming more common these days. But the limitation with these ordinary street light systems is that it lacks intelligent performance. It is very essential to automate the system so that we can conserve energy as well as to maximize the efficiency of the system. In this paper a new method is suggested so as to maximize the efficiency of the street lighting system and to conserve the energy usage the LED lights sensors. Here automation of street lights is done by LDR sensor. Intensity of led street lights can be controlled by IR sensor and pulse width modulation. It is very common these days to see solar PV based street lights. People
became aware about the importance of moving from conventional resources based energy production to renewable energy based power production. We all know that fossil fuel resources are going to fed us for only 50-60 years from now. So it is high time for us to shift to renewable energy based power production and usage as it is the only alternative available. It is sure that we can’t leave in a soci ety without power. So we need to maximize
the usage of renewable energy so that we can preserve conventional resources. Normal solar PV based street lighting system lacks automation. The problem is that it will be in on state even though there is no need of light and hence it causes loss of power. Yet another problem is power is wasted during late night when there. In this paper a new technique is suggested to automate the entire system. Here when there is no necessity of light the system will go into a pow er down mode and the lamps won’t glow. Sensors sense the intensity of light and presence sensor is used to detect the presence of humans or cars and then it gets turned on automatically. 2.10 Elvik R. Meta-analysis of evaluations of public lighting as accident. https://trid.trb.org/view.aspx?id=451827.
A meta-analysis of 37 studies evaluating the safety effects of public lighting is reported. The 37 studies contain a total of 142 results. The studies included were reported from 1948 to 1989 in 11 different countries. The presence of publication bias was tested by the funnel graph method. It was concluded that there is no evidence of publication bias and that it makes sense to estimate a weighted mean safety effect of public lighting on the basis of the 142 individual results. This is done by the log-odds method of meta-analysis. The validity of the combined results was tested against a number of rival hypotheses. It was concluded that the results are unlikely to have been caused by regression-to-the-mean and secular accident trends. The results were robust with respect to research design, decade of study, country of study, and type of traffic environment studied. The safety effects of public lighting were, however, sensitive to accident severity and type of accident. It was concluded that the best current estimates of the safety effects of public lighting are, in rounded values, a 65% reduction in nighttime fatal accidents, a 30% reduction in nighttime
injury accidents, and a 15% reduction in nighttime property-damage-only accidents. This paper appears in Transportation Research Record No. 1485, Human Performance and Safety in Highway, Traffic, and ITS Systems. Distribution, posting, or copying of this PDF is strictly prohibited without written permission of the Transportation Research Board of the National Academy of Sciences. Unless otherwise indicated, all materials in this PDF are copyrighted by the National Academy of Sciences.
CHAPTER 3 EXISTING SYSTEM
The existing systems consist of manual controls which need constant monitoring and maintenance. Considering the wastage of energy due to manual control many systems have been introduced. These systems are designed in such a manner that they could reduce their intensity and save as much energy as possible. Systems like these use LEDs (Light Emitting Diode) instead of HID (High Intensity Discharge) lamps due to dimming feature. There is a time slot allotted during which the intensity of the system keeps reducing and turns the lights OFF at morning. The time slot starts when it is specified. Reduction of intensity starts gradually at midnight when it is not much dark and there is not much traffic and is switched OFF at 6 in the morning. Some use IR (Infrared Ray) sensors to detect vehicles. Existing systems do overcome the drawbacks of HID based systems, but do not save enough energy as they are time based also in seasons like monsoon the environment remains dark compared to regular days. Winters bring the fog and if the lights are dim it could result into a great accident or disaster. Therefore, still some improvements in s ystems like these are needed. Time slot based systems consider the time slot as an advantage, but it actually is a drawback as it could not work in all conditions. As mentioned above it created problems during seasonal changes, it needs to be customized if it is to be implemented in foreign countries due to time differences. Also, if any, hardware failure or error occurs, it could be expensive to solve it. Thus, another system is needed which overcomes these drawbacks. 3.1 Disadvantages of Existing System
HID lamps consume more power.
The life time of the HID lamps is very less.
CHAPTER 4 PROPOSED SYSTEM
Street lights are controlled manually in olden days. These days’ autom ation of street
lights has emerged. But one can observe that there is no need of high intensity in peak hours i.e. when there is no traffic and even in early mornings. By reducing the intensity in these times, energy can be saved to some extent. Technical devices and methods that are enhanced by technical progress will be necessary for the realization of adaptive lighting. The tender documentation states the goals of the E-street Project and the smart ways of their future implementation. It describes the system structure and the technical requirements towards its subsystems: roadside equipment, power system, local control system, central supervisory system and communication network. The main devices and elements required to implement an automatic street light system to control the intensity of street light with better quality assurance. 4.1 Working
White Light Emitting Diode (LED) replaces HID lamps in street lighting system to include dimming feature. A microcontroller of 8051 families is used to control the intensity by developing pulse width modulated signals that drives a MOSFET to switch the LEDs accordingly to achieve desired operation. In the present system, mostly the lighting up of highways is done through High Intensity Discharge lamps (HID), whose energy consumption is high. Its intensity cannot be controlled according to the requirement so there is a need to switch on to an alternative method of lighting system i.e., by using LEDs. This system is build to overcome the present day drawbacks of HID lamps. This system demonstrates the usage of the LEDs (light emitting diodes) as the light source and its variable intensity control, according to the requirement. LED consumes less power and its life time is more, as compared to the conventional HID lamps. The more important and interesting feature is its intensity can be
controlled according to the requirement during non peak hours which is not feasible in HID lamps. A cluster of LEDs are used to form a street light. The microcontroller contains programmable instructions which controls the intensity of lights based on the PWM (Pulse width modulation) signals generated. The intensity of lights are kept high during the peak hours, as the traffic on the roads tend to decrease slowly in the late nights, the intensity also decreases progressively till morning. Finally it completely shuts down at morning 6, and again resumes at 6pm in the evening. The process is repeated. This concept in future can be enhanced by integrating it with the solar panel, which converts the solar intensity into corresponding voltage, and this energy is used to feed the highway lights. This project automatically turns on the streetlight at evening and turns off in the morning. It also controls the intensity of light. Light intensity is automatically adjusted according to the time and traffic. The number of vehicles is very low after 12AM. For example, the intensity of light is low in the evening and it starts increasing until 8PM After 8PM the light glows at full intensity and this intensity will not change. It glows on full intensity until 12AM and intensity starts decreasing after 12AM, and the lights are fully turned off after 6AM. This approach saves about 30 percentage energy. In the circuit two LEDs are also used, one is Green and other is Red. The Red LED indicates the evening and the Green Led indicates midnight time 12AM. The Arduino is not programmed for the real time, because we cannot observe the changes in live. Therefore, time delay is very low (1hr is equal to 3 second). You can change the time delay according to your use. You can make many modifications in the project according to your use, you can also use RTC (Real Time Clock) in this project. In the circuit a LDR (Light Dependent Resistor) is used, which detect the intensity of the lights, when the intensity of light comes under a fixed values the LED Light is turn
ON. But at the starting intensity of the light is low because the time is 5PM. Now the intensity is increasing with the time and light glows on full intensity at 8 PM. Intensity of the light is controlled by using PWM (pulse width modulation). The Arduino and other digital devices cannot give analog output; they can only give the digital output (High or Low). Means they can only turn OFF and turn ON the device, but sometimes we need the voltage between Vcc and GND. PWM can fulfill this requirement. PWM simply Turn On and Turn Off the output device at the high frequency. In this way the output voltage becomes under Vcc. The Arduino Nano have six PWM pins, they all are 8 bit. In other words, we can change the output value from 0 to 255 where 0 is low and 255 is High. Two LEDs are also used on Circuit, they indicates the time, RED LED turns on when LDR cross the threshold value, in my case I suppose time is 5 PM, at this time our street light (power LED) also switched on but the intensity is low. The intensity is gradually increasing and it will work on full intensity at 8 PM. Now the intensity is not changed until 12 am. After 12 AM, the Green LED is turned on and the power LED’s intensity become
low this intensity is not changed until 4 AM. After 4AM, the intensity of the light starts gradually decreasing. In addition, it becomes fully turn off at 6 AM. 4.2 Circuit Diagram of Arduino Interfacing with LED
Fig 4.1 Circuit Diagram
CHAPTER 5 BLOCK DIAGRAM
Power Supply
LDR Arduino LED’s
LCD
Atmega328 IR Sensor
Fig 5.1 Block Diagram
CHAPTER 6 HARDWARE REQUIREMENTS 6.1 ARDUINO UNO 6.1.1 OVERVIEW
The Arduino Uno is a microcontroller board based on the ATmega328 . It has 14 digital input/output pins (of which 6 can be used as PWM outputs), 6 analog inputs, a 16 MHz ceramic resonator, a USB connection, a power jack, an ICSP header, and a reset button. It contains everything needed to support the microcontroller; simply connect it to a computer with a USB cable or power it with a AC-to-DC adapter or battery to get started. The Uno differs from all preceding boards in that it does not use the FTDI USB-to-serial driver chip. Instead, it features the Atmega16U2 (Atmega8U2 up to version R2) programmed as a USB-to-serial converter. Board has the following new features: pinout : added SDA and SCL pins that are near to the AREF pin and two other new pins placed near to the RESET pin, the IOREF that allow the shields to adapt to the voltage provided from the board. In future, shields will be compatible both with the board that use the AVR, which operate with 5V and with the Arduino Due that operate with 3.3V. The second one is a not connected pin, that is reserved for future purposes. Atmega 16U2 replace the 8U2. "Uno" means one in Italian and is named to mark the upcoming release of Arduino 1.0. The Uno and version 1.0 will be the reference versions of Arduino, moving forward. The Uno is the latest in a series of USB Arduino boards, and the reference model for the Arduino platform; for a comparison with previous version 2.2 Schematic & Reference Design The Arduino reference design can use an Atmega8, 168, or 328, Current models use an ATmega328, but an Atmega8 is shown in the schematic for reference. The pin configuration is identical on all three processors. 2.3 Summary Microcontroller - ATmega328 Operating Voltage - 5V Input Voltage - 7-12V
(Recommended) Input Voltage (limits) - 6-20V Digital I/O Pins - 14 (of which 6 provide PWM output) Analog Input Pins - 6 DC Current per I/O Pin - 40 mA DC Current for 3.3V Pin - 50 mA Flash Memory - 32 KB (ATmega328) of which 0.5 KB used by bootloader SRAM - 2 KB (ATmega328) EEPROM - 1 KB (ATmega328) Clock Speed - 16 MHz 2.4 Power The Arduino Uno can be powered via the USB connection or with an external power supply. The power source is selected automatically. External (non-USB) power can come either from an AC-to-DC adapter (wall-wart) or battery. The adapter can be connected by plugging a 2.1mm center-positive plug into the board's power jack. Leads from a battery can be inserted in the Gnd and Vin pin headers of the POWER connector. The board can operate on an external supply of 6 to 20 volts. If supplied with less than 7V, however, the 5V pin may supply less than five volts and the board may be unstable. If using more than 12V, the voltage regulator may overheat and damage the board. The recommended range is 7 to 12 volts. The power pins are as follows: VIN -The input voltage to the Arduino board when it's using an external power source (as opposed to 5 volts from the USB connection or other regulated power source). You can supply voltage through this pin, or, if supplying voltage via the power jack, access it through this pin. 5V - This pin outputs a regulated 5V from the regulator on the board. The board can be supplied with power either from the DC power jack (7 -12V), the USB connector (5V), or the VIN pin of the board (7-12V). Supplying voltage via the 5V or 3.3V pins bypasses the regulator, and can damage your board. We don't advise it. 3V3- A 3.3 volt supply generated by the on-board regulator. Maximum current draw is 50 mA. GND - Ground pins. IOREF - This pin on the Arduino board provides the voltage reference with which the microcontroller operates. A properly configured shield can read the IOREF pin voltage and select the appropriate power source or enable voltage translators on the outputs for working with the 5V or 3.3V. 2.5 Memory The ATmega328 has 32 KB (with 0.5 KB used for the bootloader). It also has 2 KB of SRAM and 1 KB of EEPROM (which can be read and written with the EEPROM library).
Input and Output Each of the 14 digital pins on the Uno can be used as an input or output, using pinMode(), digitalWrite(), and digitalRead()functions. They operate at 5 volts. Each pin can provide or receive a maximum of 40 mA and has an internal pull-up resistor (disconnected by default) of 20-50 kOhms. In addition, some pins have specialized functions:
Serial: 0 (RX) and 1 (TX). Used to receive (RX) and transmit (TX) TTL
serial data. These pins are connected to the corresponding pins of the ATmega8U2 USBto-TTL Serial chip. External Interrupts: 2 and 3. These pins can be configured to trigger an interrupt on a low value, a rising or falling edge, or a change in value. See the attach Interrupt() function for details. PWM: 3, 5, 6, 9, 10, and 11. Provide 8-bit PWM output with the analog Write() function. SPI: 10 (SS), 11 (MOSI), 12 (MISO), 13 (SCK). These pins support SPI communication using the SPI library. LED: 13. There is a built-in LED connected to digital pin 13. When the pin is HIGH value, the LED is on, when the pin is LOW, it's off. The Uno has 6 analog inputs, labeled A0 through A5, each of which provide 10 bits of resolution (i.e. 1024 different values). By default they measure from ground to 5 volts, though is it possible to change the upper end of their range using the AREF pin and the analog Reference() function. Additionally, some pins have specialized functionality: TWI: A4 or SDA pin and A5 or SCL pin. Support TWI communication using the Wire library.
There are a couple of other pins on the board: AREF. Reference voltage for
the analog inputs. Used with analog Reference(). Reset. Bring this line LOW to reset the microcontroller. Typically used to add a reset button to shields which block the one on the board 2.7 Communication The Arduino Uno has a number of facilities for communicating with a computer, another Arduino or other microcontrollers. The ATmega328 provides UART TTL (5V) serial Communication, which is available on digital pins 0 (RX) and 1 (TX). An ATmega16U2 on the board channels this serial communication over USB and appears as a virtual com port to software on the computer. The '16U2 firmware uses the standard USB COM drivers, and no external driver is needed. However, on Windows, a .inf file is required. The Arduino software includes a serial monitor which allows simple textual data to be sent to and from the Arduino board. The RX and TX LEDs on the board will flash when data is being transmitted via the USB-to-serial chip and USB connection
to the computer (but not for serial communication on pins 0 and 1). A Software Serial library allows for serial communication on any of the Uno's digital pins. The ATmega328 also supports I2C (TWI) and SPI communication. The Arduino software includes a Wire library to simplify use of the I2C bus; see the documentation for details. For SPI communication, use the SPI library. The Arduino Uno can be programmed with the Arduino software. The ATmega328 on the Arduino Uno comes preburned with a bootloader that allows you to upload new code to i without the use of an external hardware programmer. It communicates using the original STK500 protocol (reference, C headerfiles). You can also bypass the bootloader an program the microcontroller through the ICSP (In-Circuit Serial Programming) header; see these instructions for details. The ATmega16U2 (or 8U2 in the rev1 and rev2 boards) firmware source code is available . The ATmega16U2/8U2 is loaded with a DFU bootloader, which can be activated by: On Rev1 boards: connecting the solder jumper on the back of the board (near the map of Italy) and then resetting the 8U2. On Rev2 or later boards: there is a resistor that pulling the 8U2/16U2 HWB line to ground, making it easier to put into DFU mode. You can then use Atmel's FLIP software (Windows) or the DFU programmer (Mac OS X and Linux) to load a new firmware. Or you can use the ISP header with an external programmer (overwriting the DFU bootloader). See this user-contributed tutorial for more information. 2.9 Automatic (Software) Reset Rather than requiring a physical press of the reset button before an upload, the Arduino Uno is designed in a way that allows it to be reset by software running on a connected computer. One of the hardware flow control lines (DTR) of theATmega8U2/16U2 is connected to the reset line of the ATmega328 via a 100 nanofarad capacitor. When this line is asserted (taken low), the reset line drops long enough to reset the chip. The Arduino software uses this capability to allow you to upload code by simply pressing the upload button in the Arduino environment. This means that the bootloader can have a shorter timeout, as the lowering of DTR can be wellcoordinated with the start of the upload. This setup has other implications. When the Uno is connected to either a computer running Mac OS X or Linux, it resets each time a
connection is made to it from software (via USB). For the Following half-second or so, the bootloader is running on the Uno. While it is programmed to ignore malformed data (i.e. anything besides an upload of new code), it will intercept the first few bytes of data sent to the board after a connection is opened. If a sketch running on the board receives one-time configuration or other data when it first starts, make sure that the software with which it communicates waits a second after opening the connection and before sending this data. The Uno contains a trace that can be cut to disable the auto-reset. The pads on either side of the trace can be soldered together to re-enable it. It's labeled "RESET-EN". You may also be able to disable the auto-reset by connecting a 110 ohm resistor from 5V to the reset line. USB Over current Protection The Arduino Uno has a resettable polyfuse that protects your computer's USB ports from shorts and over current. Although most computers provide their own internal protection, the fuse provides an extra layer of protection. If more than 500 mA is applied to the USB port, the fuse will automatically break the connection until the short or overload is removed. Physical Characteristics The maximum length and width of the Uno PCB are 2.7 and 2.1 inches respectively, with the USB connector and power jack extending beyond the former dimension. Four screw holes allow the board to be attached to a surface or case. Note that the distance between digital pins 7 and 8 is 160 mil (0.16"), not an even multiple of the 100 mil spacing of the other pins. The Arduino Uno is a microcontroller board based on the ATmega328 (datasheet). It has 14 digital input/output pins (of which 6 can be used as PWM outputs), 6 analog inputs, a 16 MHz ceramic resonator, a USB connection, a power jack, an ICSP header, and a reset button. It contains everything needed to support the microcontroller; simply connect it to a computer with a USB cable or power it with a AC-to-DC adapter or battery to get started.
Fig 6.1 Arduino Uno 6.1.1 PIN DESCRIPTION
Each of the 14 digital pins on the Uno can be used as an input or output, using pinMode(), digitalWrite(), and digitalRead() functions. They operate at 5 volts. Each pin can provide or receive a maximum of 40 mA and has an internal pull-up resistor (disconnected by default) of 20-50 kOhms. In addition, some pins have specialized functions: Input and Output
Each of the 14 digital pins on the Arduino Uno can be used as an input or output, using pinMode(), digitalWrite(), and digitalRead() functions. They operate at 5 volts. Each pin can provide or receive a maximum of 40 mA and has an internal pull-up resistor (disconnected by default) of 20-50 kOhms. In addition, some pins have specialized functions:
Serial: pins 0 (RX) and 1 (TX). Used to receive (RX) and transmit (TX) TTL serial data.
These pins are connected to the corresponding pins of the ATmega8U2 USB-to-TTL Serial chip. External interrupt: pins 2 and 3. These pins can be configured to trigger an interrupt on
a low value, a rising or falling edge, or a change in value. See the attach Interrupt() function for details. PWM: 3 , 5, 6, 9, 10, and 11. Provide 8-bit PWM output with the analogWrite() function. SPI: 10 (SS), 11 (MOSI), 12 (MISO), 13 (SCK). These pins support SPI communication
using the SPI library. LED: 13. There is a built-in LED connected to digital pin 13. When the pin is HIGH value,
the LED is on, when the pin is LOW, it’s off. The Uno has 6 analog inputs, labelled A0 through A5, each of which provide 10 bits of resolutio n (i.e. 1024 different values). By default they measure from ground to 5 volts, though is it possible to change the upper end of their range using the AREF pin and the analogReference() functio n. Additionally, some pins have specialized functionality: TWI: A4 or SDA pin and A5 or SCL pin. Support TWI communication using the Wire
library. There are a couple of other pins on the board: AREF. Reference voltage for the analog inputs. Used with analogReference(). Reset. Bring this line LOW to reset the microcontroller. Typically used to add a reset
button to shields which block the one on the board.
6.2 IR Sensor
A passive infrared sensor (PIR sensor) is an electronic sensor that measures infrared (IR) light radiating from objects in its field of view. They are most often used in PIR-based motion detectors. All objects with a temperature above absolute zero emit heat energy in the form of radiation. Usually this radiation isn't visible to the human eye because it radiates at infrared wavelengths, but it can be detected by electronic devices designed for such a purpose. The term passive in this instance refers to the fact that PIR devices do not generate or radiate energy for detection purposes. They work entirely by detecting infrared radiation emitted by or reflected from objects. They do not detect or measure "heat". Infrared radiation enters through the front of the sensor, known as the 'sensor face'. At the core of a PIR sensor is a solid state sensor or set of sensors, made from pyroelectric materials — materials which generate energy when exposed to heat. Typically, the sensors are approximately 1/4 inch square (40 mm2), and take the form of a thin film. Materials commonly used in PIR sensors include gallium nitride (GaN), caesium nitrate (CsNO3), polyvinyl fluorides, derivatives of phenylpyridine, and cobalt phthalocyanine. The s ensor is often manufactured as part of an integrated circuit. A PIR-based motion detector is used to sense movement of people, animals, or other objects. They are commonly used in burglar alarms and automatically-activated lighting systems. They are commonly called simply "PIR", or sometimes "PID", for "passive infrared detector". An individual PIR sensor detects changes in the amount of infrared radiation impinging upon it, which varies depending on the temperature and surface characteristics of the objects in front of the sensor.[2] When an object, such as a human, passes in front of the background, such as a wall, the temperature at that point in the sensor's field of view will rise from room temperature to body temperature, and then back again. The sensor converts the resulting change in the incoming infrared radiation into a change in the output
voltage, and this triggers the detection. Objects of similar temperature but different surface characteristics may also have a different infrared emission pattern, and thus moving them with respect to the background may trigger the detector as well. PIRs come in many configurations for a wide variety of applications. The most common models have numerous Fresnel lenses or mirror segments, an effective range of about ten meters (thirty feet), and a field of view less than 180 degrees. Models with wider fields of view, including 360 degrees, are available — typically designed to mount on a ceiling. Some larger PIRs are made with single segment mirrors and can sense changes in infrared energy over thirty meters (one hundred feet) away from the PIR. There are also PIRs designed with reversible orientation mirrors which allow either broad coverage (110° wide) or very narrow "curtain" coverage, or with individually selectable segments to "shape" the coverage.
Fig 6.2 IR Sensor Pairs of sensor elements may be wired as opposite inputs to a differential amplifier. In such a configuration, the PIR measurements cancel each other so that the average temperature of the field of view is removed from the electrical signal; an increase of IR energy across the entire sensor is self-cancelling and will not trigger the device. This allows the device to resist false indications of change in the event of being exposed to brief flashes of light or field-wide illumination. (Continuous high energy exposure may still be able to saturate the sensor materials and render the sensor unable to register further information.)
At the same time, this differential arrangement minimizes common-mode interference, allowing the device to resist triggering due to nearby electric fields. However, a differential pair of sensors cannot measure temperature in this configuration, and therefore is only useful for motion detection.
Fig 6.3 Pin Description The PIR sensor is typically mounted on a printed circuit board containing the necessary electronics required to interpret the signals from the sensor itself. The complete assembly is usually contained within a housing, mounted in a location where the sensor can cover area to be monitor. The housing will usually have a plastic "window" through which the infrared energy can enter. Despite often being only translucent to visible light, infrared energy is able to reach the sensor through the window because the plastic used is transparent to infrared radiation. The plastic window reduces the chance of foreign objects (dust, insects, etc.) from obscuring the sensor's field of view, damaging the mechanism, and/or causing false alarms. The window may be used as a filter, to limit the wavelengths to 8-14 micrometres, which is closest to the infrared radiation emitted by humans. 6.3 LED
A light-emitting diode (LED) is a two-lead semiconductor light source. It is a p – n junction diode that emits light when activated. When a suitable current is applied to the leads, electrons are able to recombine with electron holes within the device, releasing energy in the form of photons. This effect is called electroluminescence, and the color of the light (corresponding to the energy of the photon) is determined by the energy band gap of the semiconductor. LEDs are typically small (less than 1 mm2) and integrated optical components may be used to shape the radiation pattern. Appearing as practical electronic components in 1962, the earliest LEDs emitted low-intensity infrared light. Infrared LEDs are still frequently used as transmitting elements in remote-control circuits, such as those in remote controls for a wide variety of consumer electronics. The first visible-light LEDs were of low intensity and limited to red. Modern LEDs are available across the visible, ultraviolet, and infrared wavelengths, with very high brightness. Early LEDs were often used as indicator lamps for electronic devices, replacing small incandescent bulbs. They were soon packaged into numeric readouts in the form of seven-segment displays and were commonly seen in digital clocks. Recent developments have produced LEDs suitable for environmental and task lighting. LEDs have led to new displays and sensors, while their high switching rates are useful in advanced communications technology. LEDs have many advantages over incandescent light sources, including lower energy consumption, longer lifetime, improved physical robustness, smaller size, and faster switching. Light-emitting diodes are used in applications as diverse as aviation lighting, automotive headlamps, advertising, general lighting, traffic signals, camera flashes, lighted wallpaper and medical devices. They are also significantly more energy efficient and, arguably, have fewer environmental concerns linked to their disposal. Unlike a laser, the color of light emitted from an LED is neither coherent nor monochromatic, but the spectrum is narrow with respect to human vision, and for most purposes the light from a simple diode element can be regarded as functionally monochromatic.
An LED is a small light (it stands for "light emitting diode") that works with relatively little power. The Arduino board has one built-in on digital pin 13. 6.3.1 Connecting an LED
LEDs have polarity, which means they will only light up if you orient the legs properly. The long leg is typically positive, and should connect to a digital pin on the Arduino board. The short leg goes to GND; the bulb of the LED will also typically have a flat edge on this side.
Fig 6.4 LED In order to protect the LED, you will also need use a resistor "in series" with the LED. If the LED doesn't light up, trying reversing the legs (you won't hurt the LED if you plug it in backwards for a short period of time). 6.4 LDR
LDR ‘s or Light Dependent Resistors are very useful especially in light/dark sensor
circuits. These help in automatically switching ON /OFF the street lights and etc., normally the resistance of an LDR is very high, sometimes as very high as 1000000 ohms, but when they are illuminated with light, resistance drop dramatically. Electronic opto sensors are the devices that alter their electrical characteristics, in the presence of visible or invisible light. The best-known devices of these types are the light dependent resistor (LDR), the
photo diode and the phototransistors. LDRs or Light Dependent Resistors are very useful especially in light/dark sensor circuits. Normally the resistance of an LDR is very high, sometimes as high as 1000 000 ohms, but when they are illuminated with light resistance drops dramatically. Electronic opto sensors are the devices that alter their electrical characteristics, in the presences of visible or invisible light. The best-known devices of this type are the light dependent resistor (LDR), the photo diode and the phototransistors. Light dependent resistor as the name suggests depends on light for the variation of resistance. LDR are made by depositing a film of cadmium sulphide or cadmium selenide on a substrate of ceramic containing no or very few free electrons when not illuminated. The film is deposited in a zig zag fashion in the form of a strip. The longer the strip the more the value of resistance. When light falls on the strip, the resistance decreases. In the absence of light the resistance can be in the order of 10K ohm to 15K ohm and is called the dark resistance. Depending on the exposure of light the resistance can fall down to value of 500 oh ms. The power ratings are usually smaller and are in the range 50mw to .5w. Though very sensitive to light, the switching time is very high and hence cannot be used for high frequency applications. They are used in chopper amplifiers. Light dependent resistors are available as discs 0.5cm to 2.5cm. The resistance rises to several Mega ohms under dark conditions. The below figure shoes that when the torch is turned on, the resistance of the LDR falls, allowing current to pass through it is shown in figure.
Fig 6.5 LDR Sensor The basic construction and symbol for LDR are shown in above figures respectively. The LDR is a variable resistor whose resistance decreases with the increase in light intensity. Two cadmium sulphide (cds) photoconductive cells with spectral response similar to that of the human eye. The cell resistance falls with increasing light intensity.
Fig 6.6 LDR Circuit Features:
High reliability
Light weight
Wide spectral response
Wide ambient temperature range
Applications:
Smoke detection
Automatic lighting control
Burglar alarm systems
Camera (electronic shutter)
Strobe (color temperature reading)
6.5 Liquid Crystal Display (LCD)
LCD is a type of display used in digital watches and many portable computers. LCD displays utilize to sheets of polarizing material with a liquid crystal solution between them. An electric current passed through the liquid causes the crystals to align so that light cannot pass through them. LCD technology has advanced very rapidly since its initial inception over a decade ago for use in lap top computers. Technical achievements has resulted in brighter displace, higher resolutions, reduce response times and cheaper manufacturing process. The liquid crystals can be manipulated through an applied electric voltage so that light is allowed to pass or is blocked. By carefully controlling where and what wavelength (color) of light is allowed to pass, the LCD monitor is able to display images. A backlight provides LCD monitor‘s brightness.
Over the years many improvements have been made to LCD to help enhance resolution, image, sharpness and response times. One of the latest such advancement is applied to glass during acts as switch allowing control of light at the pixel level, greatly improving LCD ‘s ability to display small -sized
fonts and image clearly. Other advances have a llowed LCD‘s to greatly reduce liquid crystal cell response times. Response time is basically the amount of time it takes for a pixel to ―change colors‖,
in reality response time is the amount of time it takes a liquid crystal cell to go from being active to inactive. This is due to following reasons:
The declining prices of LCDs.
The ability to display numbers, characters and graphics. This is in contrast to LEDs, which are limited to numbers and a few characters.
An intelligent LCD display of two lines, 20 characters per line that is interfaced to the pic16f72 microcontroller. Incorporation of a refreshing controller into the LCD, thereby relieving the CPU to keep displaying the data. Ease of programming for characters and graphics. Most of the LCD modules conform to a standard interface specification. A 14-pin access is provided having eight data lines, three control lines and three power lines. The connections are laid out in one of the two common configurations, either two rows of seven pins, or a single row of 14 pins. One of these pins is numbered on the LCD‘s printed circuit board (PCB), but if
not, it is quite easy to locate pin1. Since this pin is connected to ground, it often has a thicker PCB track, connected to it, and it is generally connected to metal work at same point. 6.5.1 Pin Diagram of LCD
Fig 6.7 Pin Diagram
PIN DESCRIPTIONS: -
Vcc, Vss and Vee: While Vcc and Vss provide +5V and ground respectively, Vee is used for controlling LCD contrast. RS Register Select: - There are two very important registers inside the LCD. The RS pin is used for their selection as follows. If RS=0, the instruction command code register is selected, allowing the user to send a command such as clear display, cursor at home, etc. If RS=1, the data register is selected, allowing the user to send data to be displayed on the LCD. R/W, read/write: R/W input allows the user to write information to the LCD or read information from it. R/W = 1 for reading. R/W= 0 for writing. EN, enable: - The LCD to latch information presented to its data pins uses the enable pin. When data is supplied to data pins, a high – to-low pulse must be applied to this pin in order for the LCD to latch in the data present at the data pins. This pulse must be a minimum of 450 ns wide. D0 – D7: - The 8 – bit data pins, DO – D7, are used to send information to the LCD or read the contents of the LCD‘s internal registers. To display letters and numbers, we send ASCII codes for the letters A – Z, a-z numbers 0-9 to these pins while making RS=1. There are also instruction command codes that can be sent to the LCD to clear the display or force the cursor to home position or blink the instruction command codes.
We also use RS = 0 to check the busy flag bit to see if the LCD is ready to receive information. The busy flag is D7 and can be read when R/W=1 and RS=0, as follows: if R/W = 1, RS = 0. When D7= 1 (busy flag = 1), the LCD is busy taking care of internal operations and will not accept any information. Prototype circuit: For a LCD module to be used effectively in any piece of equipment, a Microprocessor or Micro controller is usually, required to drive it. However, before attempting a series of switches to the pins of the module. This can be a quite benefical step, if even you are thoroughly conversant with the workings of microprocessors. 6.6 Power Supply
Power supply block consists of following units: Step down transformer.
Bridge rectifier circuit.
Input filter.
Voltage regulators.
Output filter.
Indicator unit.
Step down transformer: The step-down transformer is used to step down the supply
voltage of 230v ac from mains to lower values, as the various IC‘s used in this project
require reduced voltages. The transformer consists of primary and secondary coils. To reduce or step down the voltage, the transformer is designed to contain less number of turns in its secondary core. The outputs from the secondary coil which is center tapped are the ac values of 0v, 15v and 15v. The conversion of these ac values to dc values to dc values is done using the full wave rectifier unit.
Rectifier Unit: A diode bridge is an arrangement of four diodes connected in a bridge
circuit. That provides the polarity of output voltage of any polarity of the input voltage. When used in its most common application, for conversion of alternating current (A.C) input into direct current (D.C) output, it is known as a bridge rectifier. The diagram describes a diode-bridge design known as a full wave rectifier. This design can be u sed to rectify single phase A.C. when no transformer center tap is available. A bridge rectifier makes use of four diodes in a bridge arrangement to achieve full wave rectification. This is a Widely used configuration, both with individual diodes wired as shown and with single component bridges where the diode bridge is wired internally. For both positive and negative swings of the transformer, there is a forward path through the diode bridge. Both conduction paths cause current to flow in the same direction through the load resister, accomplishing full-wave rectification. While one set of diodes is forward biased, the other set is reverse biased and effectively eliminated from the circuit. Input Filter: - Capacitors are used as filters. The ripples from the dc voltages are removed
and pure dc voltage is obtained. The primary action performed by capacitor is charging and discharging. It charges in positive half cycle of the ac voltage and it will discharge in negative half cycle. So it allows only ac voltage and does not allow the dc voltage. This filter is fixed before the regulator. Capacitors used here are of the value 1000uF Regulator unit: - Regulator regulates the output voltage to a specific value. The output
voltage is maintained irrespective of the fluctuations in the input dc voltage. Whenever there are any ac voltage fluctuations, the dc voltage also changes, and to avoid this regulator are used. 6.6.1 Power Supply Circuit Diagram
Fig 6.8 Power Supply Circuit Diagram
6.7 Load
In this intelligent energy saving system we are using two loads, lamp and Fan. According to the light intensity of the particular room or cabin the LDR will senses, depending on the LDR output the lamp will be ON/OFF. This system is only applicable for lamps and not applicable for tube lights, because the starting voltage of the tube lights is high compared to lamps. By using Relay we can adjust the speed of the Fan according to the changes of the room temperature.
CHAPTER 7 SOFTWARE REQUIREMENTS
In this system, following software’s are used, 1.ARDUINO IDE 2.LIBRARIES 3.EMBEDDED C 4.HOSTING WEBSITE – Ubidot.com 7.1 ARDUINO IDE
Arduino is a prototype platform (open-source) based on an easy-to-use hardware and software. It consists of a circuit board, which can be programed (referred to as a microcontroller) and a ready-made software called Arduino IDE (Integrated Development Environment), which is used to write and upload the computer code to the physical board. Arduino provides a standard form factor that breaks the functions of the micro-controller into a more accessible package. Arduino is a prototype platform (open-source) based on an easy-to-use hardware and software. It consists of a circuit board, which can be programed (referred to as a microcontroller) and a ready-made software called Arduino IDE (Integrated Development Environment), which is used to write and upload the computer code to the physical board. The key features are: Arduino boards are able to read analog or digital input signals from different
sensors and turn it into an output such as activating a motor, turning LED on/off, connect to the cloud and many other actions. You can control your board functions by sending a set of instructions to the
microcontroller on the board via Arduino IDE (referred to as uploading software).
Unlike most previous programmable circuit boards, Arduino does not need an
extra piece of hardware (called a programmer) in order to load a new code onto the board. You can simply use a USB cable. Additionally, the Arduino IDE uses a simplified version of C++, making it easier
to learn to program. Finally, Arduino provides a standard form factor that breaks the functions of the
micro-controller into a more accessible package. Various kinds of Arduino boards are available depending on different microcontrollers used. However, all Arduino boards have one thing in common: they are programed through the Arduino IDE. The differences are based on the number of inputs and outputs (the number of sensors, LEDs, and buttons you can use on a single board), speed, operating voltage, form factor etc. Some boards are designed to be embedded and have no programming interface (hardware), which you would need to buy separately. Some can run directly from a 3.7V battery, others need at least 5V.
Arduino consists of both a physical programmable circuit board (often referred to as a microcontroller) and a piece of software, or IDE (Integrated Development Environment) that runs on your computer, used to write and upload computer code to the physical board. Arduino is an open source computer hardware and software company, project, and user community
that
designs
and
manufactures
single-board
microcontrollers
and
microcontroller kits for building digital devices and interactive objects that can sense and
control objects in the physical world. The project's products are distributed as open-source hardware and software, which are licensed under the GNU Lesser General Public License (LGPL) or the GNU General Public License (GPL) permitting the manufacture of Arduino boards and software distribution by anyone. Arduino boards are available commercially in preassembled form, or as do-it-yourself (DIY) kits. Arduino board designs use a variety of microprocessors and controllers. The boards are equipped with sets of digital and analog input/output (I/O) pins that may be interfaced to various expansion boards (shields) and other circuits. The boards feature serial communications interfaces, includ ing Universal Serial Bus (USB) on some models, which are also used for loading programs from personal computers. The microcontrollers are typically programmed using a dialect of features from the programming languages C and C++. In addition to using traditional compiler toolcha ins, the Arduino project provides an integrated development environment (IDE) based on the Processing language project. 7.2 LIBRARIES
The Arduino environment can be extended through the use of libraries, just like most programming platforms. Libraries provide extra functionality for use in sketches, e.g. working with hardware or manipulating data. To use a library in a sketch, select it from Sketch > Import Library. A number of libraries come installed with the IDE, but you can also download or create your own. See these instructions for details on installing libraries. Standard Libraries Used
Ethernet-for connecting to the internet using the Arduino Ethernet Shield, Arduino
Ethernet Shield 2 and Arduino Leonardo ETH.
PCD8544 - for controlling or to communicate with Nokia 5110 lcd.
Wi-Fi - for connecting to the internet using the Arduino Wi-Fi shield.
Ubidot Library- to connect with ubidot.com.
7.3 EMBEDDED C
Embedded C is a set of language extensions for the C programming language by the C Standards Committee to address commonality issues that exist between C extensions for different embedded systems. Historically, embedded C programming requires nonstandard extensions to the C language in order to support exotic features such as fixed-point arithmetic, multiple distinct memory banks, and basic I/O operations. Embedded Programming
Embedded refers to the combination of hardware and software. Embedded systems programming is the programming of an embedded system in some device using the permitted programming interfaces provided by that system. EmbeddedJava is an example of a development environme nt for programming embedded systems that will execute Java programs. Arduino is a very minute part of embedded systems, in fact we can call it as an application product of embedded system. Arduino is just any other microcontroller board, with a specifically designed API and software which makes programming it very easy. Arduino is just a drop of water in Embedded System Ocean. 3.4 UBIDOTS.COM (HOSTING WEBSITE)
Ubidots was first born as an engineering services firm, specializing in hardware and software development for IoT projects in Latin America. Between 2012 and 2014, we accomplished hundreds of Internet of Things projects across industries like Healthcare, Oil & Gas, Energy, Manufacturing, Transportation and Retail, learning the nuts and bolts of IOT. After going through the Boston Mass Challenge Accelerator -with a purpose of turning ourselves into a global product-based startup- the idea of an IOT cloud was born; specially one that understood the real needs of hardware engineer. Since its launch in 2014, the ubidots Cloud has grown into one of the top IoT Platforms in the market, supporting thousands of IOT initiatives in more than 40 countries.
CHAPTER 8 CONCLUSION
This paper elaborates the design and construction of Arduino based LED street light auto intensity control system circuit. Circuit works properly to turn street light LED ON/OFF. After designing the circuit which controls the intensity of street light as illustrated in the previous sections LDR sensor and the photoelectric sensors are the two main components working in the circuit. If the two conditions have been satisfied the circuit will do the desired work according to specific program. Each sensor controls the turning ON or OFF the lighting column of street light. The intensity of Street lights has been successfully controlled by Arduino board. Street-lights are a large consumer of energy for cities using up to 30-50% of energy budget. If every city installs the proposed system, then a lot of power can be saved. Proposed system is power saving mechanism for LED Street lights by using Arduino Board. It turns out most reliable and time efficient way to switch ON/OFF street-lights. It provides an effective measure to save energy by preventing unnecessary wastage of electricity, caused due to manual switching or lighting of streetlights when it is not required. It adopts a dynamic control methodology for traffic flow. The proposed system is especially appropriate for street lighting in remote urban and rural areas where the traffic is low at times. The system is versatile, extendable and totally adjustable to user needs.
CHAPTER 9 REFERENCES
[1] M Popa, C Cepisca. Energy consumption saving solutions based on intelligent street lighting control system. U P B Sci Bull, 73:297-308, 2011. [2] Schwab R N, Walton N E, Mounce J M and Rosenbaum M J. Synthesis of safety research related to traffic control and roadway elements. Volume 2, Chapter 12, Highway Lighting. Report No. FHWA-TS-82233. Federal Highway Administration, 1982. [3] Donald A Cleland. Street light monitoring and control. United States of America Patent US 8,290,710 B2, 16 October 2012. [4] D A Devi and A Kumar. Design and implementation of CPLD based solar power saving system for street lights and automatic traffic controller. International Journal of Scientific and Research Publications, 2(11):1-4, 2012. [5] Divya Guddeti. Design and implement of wireless sensor street light control and monitoring strategy along with GUI. IJITR, 78-81, 2016. [6] S Srivastava. Automatic street lights. Advance in Electronic and Electric Engineering, 3(5):539- 342, 2013. [7] Ahmed Sharique Anees, Anupriya, Ayushy Chowdhary, Shalini Dubey, Shweta Verma. Solar powered led streetlight with automatic intensity control. International Journal of Innovative Research in Electrical, Electronics, Instrumentation and Control Engineering, 3(6):32-36, 2013. [8] Arduino Based Auto Street Light Intensity Controller (PDF Download Available). Availablehttps://www.researchgate.net/publication/316889619_Arduino_Based_Auto_St reet_Light_Intensity_Controller [accessed Mar 13 2018].
