GSM Based Lighting Control System Using Microcontroller
EE 199 Research Proposal
Rodelyn B. Cañizares B.S. Electrical Engineering
1.0 Introduction 1.1
Background of the Study
Lighting is a major source of electricity consumption.Commercial public sector buildings and residential houses account for 43% of the electricity used for lighting. There are common problems that home owners encountered in relation with lighting system. One of this is due to some negligence like leaving the lights ON results of having greater power consumption. This additional power consumption that wasted varies directly to our electrical bills. Another problem is for those busy home owners who will arrive home late at night; they want to have immediate access to turn on the lights to have preventive measures against robbery and crimes. On the other hand Global System for Mobile Communication (GSM) technology is most popular nowadays. Short Messages Services (SMS) using GSM is considered as the cheapest and reliable means of communication. The Philippines have the largest population of mobile subscribers who uses text messaging as a means of communication. An average of 20 text messages is being sent daily by a subscriber. Because of this, the Philippines have been considered as the text capital of the world. On 2007 alone, there are 42.70 million people who are subscribers of mobile phones. [1] Mobile devices, such as mobile phones, are becoming multipurpose devices. The researcher proposes a system that allows the user to control lighting systems remotely using mobile phones. It provides remote control via Short Messages Services (SMS) using Global System for Mobile Communication (GSM) technology. This system can be used when the user is away from the place. The user only needs to use his cell phone in order to monitor and control the lights in their house. This system is related on the past study which uses personal computer (PC) that contains the software components through which the lights and appliances are controlled and home security is monitored [2]. Regarding with this project, the researcher wants to develop a system that uses a microcontroller instead of PC. Using microcontroller will result to have a reduced size system and economical to digitally control even more lights [3].
1.2
Project Objectives 1. Build a control system that used to control lighting system using SMS feature of GSM technology. 2. To use microcontroller to control the operation of the lighting system and make the system economical compare with PC interfacing. 3. To develop software program to control the message received.
1.3
Overview Switch
Mobil e phone 1
Light
Relay
SMS Microcontroller Mobil e phone 2
Power supply SMS Reading and saving
Searching for control words
Compare with control
Reset
Figure1-1. The block diagram of the GSM based Switch control Figure 1-1 shows how the system operates. The system is based on GSM technology for transmission of SMS from sender to receiver. Mobile phone 2 received the SMS message sent by mobile phone 1. As the mobile phone 2 is recognized by the microcontroller, then the received message sends to the microcontroller. The microcontroller read the message and saves. Searching inside the SMS message for any control words available this is done by using the appropriate program. The program will manage the SMS data and compares with available control words. When the program find the control words inside the message, then, the program will prepare to send the desired signals to the lighting system through relays. The program automatically deletes the saved message, so as to prepare to receive new SMS message.
2.0 Review of Related Literature 2.1 Lighting System Residential houses and offices about 20 to 50 percent of total energy is consumed due to lighting load. Most importantly, for some buildings over 90 percent of lighting energy consumed can be an unnecessary expense through over-illumination. The cost of that lighting can be substantial. A single 100 W light bulb used just 6 hours a day can cost over $25 per year to use (.12/kWh). Thus lighting represents a critical component of energy use today, especially in large office buildings where there are many alternatives for energy utilization in lighting. There are several strategies available to minimize energy requirements in any building: • • • • • • • •
Specification of illumination requirements for each given use area. Analysis of lighting quality to ensure that adverse components of lighting (for example, glare or incorrect color spectrum) are not biasing the design. Integration of space planning and interior architecture (including choice of interior surfaces and room geometries) to lighting design. Design of time of day use that does not expend unnecessary energy. Selection of fixture and lamp types that reflect best available technology for energy conservation. Training of building occupants to utilize lighting equipment in most efficient manner. Maintenance of lighting systems to minimize energy wastage. Use of natural light - some big box stores are being built (ca 2006 on) with numerous plastic bubble skylights, in many cases completely obviating the need for interior artificial lighting for many hours of the day.
REQUIRED LIGHTING OUTLETS (a) At least one wall switch-controlled lighting outlet shall be installed in every habitable room: in bathrooms, hallways, stairways, attached garages, detached garages with electric power, and at outdoor entrances or exits. The lighting outlet for interior stairways shall have a wall switch at each floor level where the difference between floor levels is six steps or more. (b) At least one wall switch controlled lighting outlet shall be installed in an attic, under-floor space, utility room, and basement, where these spaces are used for storage or contain equipment requiring servicing. The switch shall be located at the point of entry to these areas, and the lighting outlet located at or near the equipment requiring servicing. HOMEOWNERS GUIDE FOR RESIDENTIAL WIRING Based on the 2002 National electrical Code
2.1.1 Lighting Switch Control Once you have formulated a lighting design, it is important to decide how to regulate the system or control the lighting design to achieve the desired effect. There are many options, from simple switches to preset multiple-zone/ multiple-scene controllers. Every room is capable of being viewed and used in numerous ways. A multiple-scene controller allows the same lights to be illuminated at various levels by a single control unit. Multiple scene controllers can do this at the push of a button. 2.1.1.1 Momentary Contact Switches Momentary contact switches (door jam switches) are devices that turn on the light when the door is opened. It’s the same way the light in your refrigerator operates. When the door is shut, the light automatically goes out. This works only if the household members remember to shut the door completely. Bi-fold doors don’t work well with momentary contact switches because the need to be fully closed to make a good connection. 2.1.1.2 Motion Sensors Motion sensors turn on the lights as someone enters the room or closet and keeps them on as long as there movement or for a certain length of time, as preset in the sensor. Some companies make motion sensors with manual override for clients who plan to spend a great deal of time in a particular room without moving around. For instance, if there is a safe in the master-bedroom closet and home owners occasionally review important papers or sort of jewelry there, an override on the motion sensor in this location would be advisable. 2.1.1.3 Panic Switches Panic Switches are switches normally located in the master bedroom that turn on exterior perimeter lights. No home owners want to run to the front door when there is suspicious noise outside at night- most people don’t even want to get out of bed. This will also allow the occupants to turn off the outside or entry lights if they are left unintentionally. 2.1.1.4 Sound Actuated Switches A sound-actuated switches including a microphone coupled via an audio amplifier to a reset circuit. These devices turn on the lights when a noise is made. When a sound of sufficient intensity is received by the microphone a reset signal is supplied to the counter portion of an oscillator and counter circuit. The counter then begins counting oscillations and produces an "on" control signal until a predetermined count is reached, at which time an "off" control signal is produced.[5]
2.2 Global system for mobile communication (GSM) Global system for mobile communication (GSM) is a globally accepted standard for digital cellular communication. GSM is the name of a standardization group established in 1982 to create a common European mobile telephone standard that would formulate specifications for a pan-European mobile cellular radio system operating at 900 MHz. It is estimated that many countries outside of Europe will join the GSM partnership.
2.2.1 The Switching System The switching system (SS) is responsible for performing call processing and subscriberrelated functions. The switching system includes the following functional units: 2.2.1.1 Home location register (HLR) The HLR is a database used for storage and management of subscriptions. The HLR is considered the most important database, as it stores permanent data about subscribers, including a subscriber's service profile, location information, and activity status. When an individual buys a subscription from one of the PCS operators, he or she is registered in the HLR of that operator. 2.2.1.2Mobile services switching center (MSC) The MSC performs the telephony switching functions of the system. It controls calls to and from other telephone and data systems. It also performs such functions as toll ticketing, network interfacing, common channel signaling, and others. 2.2.1.3 Visitor location register (VLR) The VLR is a database that contains temporary information about subscribers that is needed by the MSC in order to service visiting subscribers. The VLR is always integrated with the MSC. When a mobile station roams into a new MSC area, the VLR connected to that MSC will request data about the mobile station from the HLR. Later, if the mobile station makes a call, the VLR will have the information needed for call setup without having to interrogate the HLR each time. • authentication center (AUC)—A unit called the AUC provides authentication and encryption parameters that verify the user's identity and ensure the confidentiality of each call. The AUC protects network operators from different types of fraud found in today's cellular world. • equipment identity register (EIR)—The EIR is a database that contains information about the identity of mobile equipment that prevents calls from stolen, unauthorized, or defective mobile stations. The AUC and EIR are implemented as stand-alone nodes or as a combined AUC/EIR node.
2.3 Microcontroller
Microcontrollers are hidden inside a surprising number of products these days. If your microwave oven has an LED or LCD screen and a keypad, it contains a microcontroller. All modern automobiles contain at least one microcontroller, and can have as many as six or seven: The engine is controlled by a microcontroller, as are the anti-lock brakes, the cruise control and so on. Any device that has a remote control almost certainly contains a microcontroller: TVs, VCRs and high-end stereo systems all fall into this category. Nice SLR and digital cameras, cell phones, camcorders, answering machines, laser printers, telephones (the ones with caller ID, 20-number memory, etc.), pagers, and feature-laden refrigerators, dishwashers, washers and dryers (the ones with displays and keypads)... You get the idea. Basically, any product or device that interacts with its user has a microcontroller buried inside. What is a Microcontroller? A microcontroller is a computer. All computers -- whether we are talking about a personal desktop computer or a large mainframe computer or a microcontroller -- have several things in common: •
• • •
All computers have a CPU (central processing unit) that executes programs. If you are sitting at a desktop computer right now reading this article, the CPU in that machine is executing a program that implements the Web browser that is displaying this page. The CPU loads the program from somewhere. On your desktop machine, the browser program is loaded from the hard disk. The computer has some RAM (random-access memory) where it can store "variables." And the computer has some input and output devices so it can talk to people. On your desktop machine, the keyboard and mouse are input devices and the monitor and printer are output devices. A hard disk is an I/O device -- it handles both input and output.
The desktop computer you are using is a "general purpose computer" that can run any of thousands of programs. Microcontrollers are "special purpose computers." Microcontrollers do one thing well. There are a number of other common characteristics that define microcontrollers. If a computer matches a majority of these characteristics, then you can call it a "microcontroller": •
• •
Microcontrollers are "embedded" inside some other device (often a consumer product) so that they can control the features or actions of the product. Another name for a microcontroller, therefore, is "embedded controller." Microcontrollers are dedicated to one task and run one specific program. The program is stored in ROM (read-only memory) and generally does not change. Microcontrollers are often low-power devices. A desktop computer is almost always plugged into a wall socket and might consume 50 watts of electricity. A batteryoperated microcontroller might consume 50 milliwatts.
•
A microcontroller has a dedicated input device and often (but not always) has a small LED or LCD display for output. A microcontroller also takes input from the device it is controlling and controls the device by sending signals to different components in the device. For example, the microcontroller inside a TV takes input from the remote control and displays output on the TV screen. The controller controls the channel selector, the speaker system and certain adjustments on the picture tube electronics such as tint and brightness. The engine controller in a car takes input from sensors such as the oxygen and knock sensors and controls things like fuel mix and spark plug timing. A microwave oven controller takes input from a keypad, displays output on an LCD display and controls a relay that turns the microwave generator on and off.
• •
A microcontroller is often small and low cost. The components are chosen to minimize size and to be as inexpensive as possible. A microcontroller is often, but not always, ruggedized in some way. The microcontroller controlling a car's engine, for example, has to work in temperature extremes that a normal computer generally cannot handle. A car's microcontroller in Alaska has to work fine in -30 degree F (-34 C) weather, while the same microcontroller in Nevada might be operating at 120 degrees F (49 C). When you add the heat naturally generated by the engine, the temperature can go as high as 150 or 180 degrees F (65-80 C) in the engine compartment. On the other hand, a microcontroller embedded inside a VCR hasn't been ruggedized at all.
The actual processor used to implement a microcontroller can vary widely. For example, the cell phone shown on Inside a Digital Cell Phone contains a Z-80 processor. The Z-80 is an 8bit microprocessor developed in the 1970s and originally used in home computers of the time. The Garmin GPS shown in How GPS Receivers Work contains a low-power version of the Intel 80386, I am told. The 80386 was originally used in desktop computers. In many products, such as microwave ovens, the demand on the CPU is fairly low and price is an important consideration. In these cases, manufacturers turn to dedicated microcontroller chips -- chips that were originally designed to be low-cost, small, lowpower, embedded CPUs. The Motorola 6811 and Intel 8051 are both good examples of such chips. There is also a line of popular controllers called "PIC microcontrollers" created by a company called Microchip. By today's standards, these CPUs are incredibly minimalistic; but they are extremely inexpensive when purchased in large quantities and can often meet the needs of a device's designer with just one chip. A typical low-end microcontroller chip might have 1,000 bytes of ROM and 20 bytes of RAM on the chip, along with eight I/0 pins. In large quantities, the cost of these chips can sometimes be just pennies. You certainly are never going to run Microsoft Word on such a chip -- Microsoft Word requires perhaps 30 megabytes of RAM and a processor that can run
millions of instructions per second. But then, you don't need Microsoft Word to control a microwave oven, either. With a microcontroller, you have one specific task you are trying to accomplish, and low-cost, low-power performance is what is important.
“How Microcontrollers Work” http://electronics.howstuffworks.com/microcontroller.htm
References: 1. The History of Text Messaging.August 31, 2009 by DavidH. http://www.vxcl.org.htm 2. Khiyal, Malik Sikandar Hayat Khiyal.SMS Based Wireless Home Appliance Control System
for
Automating
Appliances
and
Security.http://iisit.org/Vol6/IISITv6p887-
894Khiyal592.pdf (2009). 3. Microcontroller. http://en.wikipedia.org/wiki/Microcontroller. (August 2009). 4. SMS Control Systems.(2006-2008). http://www.smscs.co.za/overview.htm http://www.emo.org.tr/ekler/8808cfb5939be38_ek.pdf 5.Whitehead,Randall, Residential Lighting: A Practical Guide. Wiley and Sons Inc., 2004.