Development of a Program for Control of a Home Alarm System - Term Paper Example

Faculty of Engineering and Environment BENG (HONS) ELECTRICAL AND ELECTRONIC ENGINEERING Module title: Digital and C Programming Module code: ------ Assignment: Home Alarm system Value: ------ Assignment Tutor: ------- Student Name: ----- ID: ------ Submission date: ------ Table of Contents Faculty of Engineering and Environment 1 BENG (HONS) ELECTRICAL AND ELECTRONIC ENGINEERING 1 Module title: Digital and C Programming 1 Value: ------ 1 Introduction 4 Schematic diagram of the Alarm system 4 C program for the PIC using the Source Boost IDE 7 Screen shots of your simulations with Source Boost IDE 9 Additional feature 10 Testing of program 12 Additional of LCD using 4 bit 13 Conclusion 15 References 16 Introduction The main aim of this project is to design an alarm system for homes which will use PIC18f2520 that has 3 ports which are used for LCD and the alarm system. The switches and PIC18f2520 will be interface and the switches. The home alarm system responds with a siren for 20seconds when there is an intruder in one of the rooms and the light remains flashing to show the user where the intruder until it is reset again. A home alarm system of this nature is critical to the users of home. This warning system was designed to turn on an LED light when an intruder enters the home or one uses an authorised predetermined entry, using the movement sensor as well as touch sensor. The software has been applied to produce the necessary system. Schematic diagram of the Alarm system A Schematic diagram of the Alarm system showing the sensor inputs, the LED outputs and the connections for the LCD. The following is the block diagram for the proposed alarm system. Alarm system The alarm system shown above has 5 sensors which are situated in the hallway, bathroom, sitting room, kitchen and bedroom. Once the baton or the start key on those poison are activated it takes 10 seconds for the system to raise the alarm. The magnetic sensors in this positions will act as input sensors which detects entry of an intruder and signals are send to shown indicator as well as sound is raised thus reading to the detection of entry point of the intrude. The alarm system also flashes once detection is noted. The system is reset using the operating key the alarm system designed is only able to stop flashing by resetting it. The main reason for this is ensuring that the user is able to know that there was an intruder in the home. Figure 1: State diagram that shows control of the traffic lights. State Bath LED Hall LED Kitchen LED Sitting LED Bed LED Bath LED Time OFF 1 0 0 0 0 1 INIFITY ALARM_ON 0 1 0 0 1 1 10s LIGHTS ON 0 0 1 1 0 0 30s Terminated 0 1 1 0 1 0 off portb Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0 output portb b7 b6 b5 b4 b3 b2 b1 b0 output Alarm Alarm ind Bath LED Hall LED Kitchen LED Sitting LED Bed LED Keys: (Alarm ind) that means alarm indicator. (Bath LED) that means Bathroom LED. (Hall LED) that means Hall way LED. (Kitchen LED) that means Kitchen LED. (Sitting LED) that means Sitting room LED. (Bed LED) that means Bed room LED. (Portb) = 0b00100001 // that mean bit (0) and bit(5) ON and the other bits OFF In this case, the LED is placed across the circuit when there is no intrusion then voltage = 0 in the reading then the alarm is off and there is no current. This means the emitter is zero; therefore, there will be no current that will flow when the LED is off when alarm is off. However when there is intrusion the LED is activated and v=12v, we expect the flow of current passing through the resistor and the voltage will be 12v, because the amount of current that passes through volts as the circuit. Then the flash becomes ready; the capacitor is discharged quickly through the flash which leads to the alarm to go on. When the flashing is off there are no output at Vin but when it is on there is an output. At this point it is noted that V0 increases as result of sensor resistance from the increase in V1. Some of the resistance 100k and 10k are connected to provide load resistance and help form voltage. The circuit provides a stable current through the divider and produces a voltage drop across the PIC18f2520. As a result, the output voltage VR is a function of current concentration. C program for the PIC using the Source Boost IDE The C program for the for the PIC using the Source Boost IDE is as shown below; At the start of the code shown, inputs are assigned to the Hall sensor, Bedroom sensor, Sitting room, Kitchen sensor and the bathroom sensor. The two LEDs plugged into output of the corresponding to each room sensors respectively are then coded to give a digital output of LED off when the corresponding input voltage is below a certain value and LED on when the corresponding input voltage is above a certain value. For the for any intrusion sensor, the associated LED light is made to stay on until there is reset. The output responses are five LED lights, one LED assigned to each input sensor. These are controlled by a digital output from the microcontroller as a result of the intrusion. Screen shots of your simulations with Source Boost IDE T Each sensor will require Intrusion detection system which will be located at the entrance to the room. The alarm system will use on and off circuit system thus relying on continuous flow of power which is also activates the flash intrusion occurs. Meaning the alarm will go off whenever an intruder comes in. In a closed system, the sensor is used to block off the electrical current, meaning the alarm will go off whenever the current is able to flow through the circuit. But it will also have speakers has got a control box with its own power source which is connected to all circuit connections as well as the alarm. Once the alarm sound is on, it can only be turned off by making a correctional measure is made or the user leaves the vicinity of the motion detectors. This means that there are number of offset sources which include, amplifier, and sensor, this also acts as voltage follower. At times in circuits, currents periodically change direction. An ac power supply periodically reverses the polarity of its flow. Additional feature The additional feature is the key pad as shown in the figure below; When there are changes in variables a signal is transmitted to a computer through a number of wires. This is to ensure that the signal is received by the computer. A triplex channel, for instance, includes three such channels. After the computer receives the signal, it performs a number of calculations chief of which involves adding signal voltages, before dividing them by the number of channels received. This gives he average signal voltage. Another channel is then added to the three signals, and the four signals then sent to the digital control on the control surface. This moves the surface. A series of potentiometers within the actuator then returns a signal to the computer to report the current position of the digital controller. This signal is usually a negative signal. When the desired position of the actuator is attained, the outgoing and incoming signals cancel out each other thereby stationing the digital control at its present position. One end of these cables is connected to the computer and the other to a connector. The whole process majorly involves chain reactions. That is, one computer generates and transmits a signal of its desired action. This signal is transmitted through the cables, to the connector, back to the cables, then through the connector again, then to the cables again and eventually to their intended receiving computer. Connectors are grouped into various forms. The feedback signal to the computer ensures that there is information regarding the digital control that is being relayed. This signal is usually appositive signal and it is relayed when the desired results as been attained. These sensors are capable of sensing any changes in variables. With these, any movements of the fan causing signals to be sent to the computer. These signals cause automatic movements in control digital controls thereby stabilizing the fan. The flexibility of the fan control system is improved tremendously because the computers are capacitated to receive signals from a myriad of sensors. The digital system also increases electronic stability since the control system depends less on the input values of critical electrical components as it happens in the digital systems. Testing of program The alarm was then tested in the laboratory and the results is as shown below; Alarm testing From the screenshots above it can be noted that once an intruder enters the room the current increases due to magnetic sensor leading to sending of signals to the LCD which raises an alarm. It was connected using 3-pin header and the result was run and the output for the simulation of the program is shown below; Additional of LCD using 4 bit In adding a LCD in 4-bit mode a number of pins are required in this case last four pins are used to interface. This is shown in the diagram below; The connection is done by following the following steps This is incorporated into the system as shown below; We have designed a home based system which will be used in alerting the user of a home when there was an authorized intrusion. The system was designed in a such manner that it sends sound for 20 seconds when an intruder enters a room and it stops making sound but will continue flashing until it is reseat, the system have been tested and the result indicated in the paper above. The system is ideal for homes which are in insecurity prone areas. It should be noted that access to the place will require use of a code. Conclusion A basic home alarm system was successfully constructed in this project. Along the way we encountered many problems, learning that programming code must be perfect to run properly. We also found that our laboratory sensors don’t have the ranges necessary to be implemented in a real life home alarm system, as the operating ranges of our sensors generally didn’t lie within the values that should set an alarm off. References Nilsson, J. & Riedel, S., 2010. Electric Circuits. New York: Prentice Hall Rahman, M., Karim, Z., Nyeem, S., Khan, F., Matin, G., 2015. Microcontroller Based Home Security and Load Controlling Using Gsm Technology. I. J. Computer Network and Information Security, 2015, 4, 29-36 Shah, LS & MacGregor, FJ., 2005.Dynamics and Control of Process Systems. Oxford: Elsevier Smith, KC & Sedra AS. 2009. Microelectronic Circuits. Oxford: Oxford University Press. Zungeru, A..M., Edu, U., & Garba, A. 2012. Design and Implementation of a Short Message Service Based Remote Controller. Computer Engineering and Intelligent systems, 3(4), 106–119. Read More