The title of this project is "Home Security System". This project is designed to low to medium income families which usually live in flat or apartment and develop a combination system that able to detect motion which is illegal intruder and heat or temperature that might be fire accident could be happened in anytime Then the systems will activate the output devices like buzzer, emergency light and so on to alert the user in order to allow the user to take the further action. All the systems are interfacing with each other by using wireless system concept. The function control the zone on or off individually and the checking status of the zone also available to allow the user know the condition of zone whether it got any failure or not by using remote control. Furthermore if the alarm has been activated, the user can turn off the alarm by using remote control. The technique of detecting the motion and the heat has been discussed. The system able to detect the motion in the range of 6 meter by using Pyroelectric Infrared sensor (PIR) and he heat detector sensor able to detect the heat which temperature limit is setting to 40 degree Celsius by using Thermistor. Then the systems able to interface one of each other by using of radio frequency in the range of 30 meters after testing. As the conclusion, the project able to achieve the objective that targeting and designing the system for low to medium income families.
1. Introduction
From before until now, fire accident and burglary case very often happened in anytime and anywhere. It is very commonly seen in newspaper, internet and other media resource. But this few years, the amounts of fire accident and burglary case are increasing rapidly from year to year and it becomes one of the major causes of death or injuries after road accident. Thus installed home security system in almost every home becomes very basic requirement to protect life and property.
Even though home security system has been installed in almost every home, the fire accident or burglary case still can be happened. This will happened because of certain reason like firstly most of home security system in the market only has limited function only. Most of them either only detect fire or only detect motion; combination of two functions will cause whole system more expensive and make the user not affordable to buy it. Secondly, most of home security system in the market are wired system and very easy causing malfunction because wire. Wire very easily affected by other factor like ageing, rat and so on will cause disconnection from sensors and unable to alert the user when incident happened. And lastly, sensors inside the home security system are malfunctioning because of aging or power failure. The most of electrical product will affect by aging problem including sensor. The sensors will not become sensitive to detect or sense after few year period and it will easily failure when incident happened.
So idea of "Home security system" has been developed for home user especially low to medium income family which able to detect motion, heat in wireless system. The additional features like LCD display, buzzer and emergency light to alert and protect the user from incident. The system basically separate to 3 sub-systems which is remote control, sensors unit and alarm unit. These 3 sub-systems will be interfacing each other by using RF transmitter and receiver. The user need to key in the default password in remote control to login the system then can select the zones individually either on or off then armed or disarmed the system and check the status of the zone whether it has any failure or not. Besides that, the user also can turn off the alarm that triggered by heat or motion detector sensor in sensors unit by using remote control. If the system detects any failure of the zone, the system will also trigger the alarm then indicate which zone in failure mode by LED in alarm unit to alert the user.
2. Literature review
Home automation is a system that uses to help the resident to do the household activity or housework. These housework or household activity can be from pet feeding, plant watering, home entertainment system and so on. It can be operate either automatically or sometime control remotely which all depend to the home resident [1]. The entire system can be controlled by using from remove control, computer, internet until telephone. The home automation covered very wide of hoe system and it is also including home security system. The home security system basically can be separate to five categories [2], there are:
Detection of intrusion
Simulation of presence
Detection of fire, gas and water
Medical alert and precise
Safe closing of blind
For this project, only 2 categories have been discussed. There are detection of intrusion and detection of fire. And there are 4 types of intrusion which are [2]:
i) Detection of movement ii) Magnetic contact of door or window iii) Glass breaking and pressure change iv) Pressure change
For another category which is detection of fire, there also have several techniques to detect it. These techniques are sensing in temperature, humidity and smoke [2] and sensing in temperature will be discussed in this project.
2.1 Motion Detector Technology
Generally, 3 type of motion detector technology is available. They are:
2.1.1 Infrared motion detector
The concept of infrared motion sensor is using the infrared light spectrum to measure the heat of objects that pass in front of it. The infrared motion sensor can be separated to active or passive where:
Active: Generate multiple beam of modulated infrared energy and receive any interrupt or change of received energy [3].
Figure 1: Operation of active infrared sensor [4]
Passive: detect electromagnetic radiated energy that generate by external sources like thermal energy [3].
Figure 2: Operation of passive infrared sensor [5]
2.1.2 Microwave motion detector
Figure 3: Operation of microwave motion sensor [6]
The operation of microwave motion detector is covering area with electronic field and receive any disturb or movement of electronic field. It can separate to bistatic and monostatic [7]. The bistatic type contains emitter and receiver which operate separately to configure the beam to fit particular situation. , the monostatic type can define detection area based on microwave beam that it emits.
2.1.3 Ultrasonic motion detector
The operation of ultrasonic motion detector is detecting the movement by generating the sound wave in the ultrasonic frequency range around 30 kHz to 50 kHz within the limited area [8].
Figure 3: Operation of ultrasonic motion detector [9]
2.2 Heat Detector Technology
Generally, only 3 type of motion detector technology is mention. They are:
2.2.1 Thermocouple
It consist junction of 2 types of metal that joined together will produce voltage which varies with temperature change [10].
Advantages
i) Can be used in wide temperature ii) Fast response
Disadvantages
i) Low accuracy ii) short life time
2.2.2 Resistance thermometer (RTD)
It is an electrical resistance of pure metal will increase with rise of temperature [11].
Advantages
i) High accuracy ii) Good stability
Disadvantages
i) Slow response ii) High cost
2.2.3Thermistor
It is a type of ceramic resistor that resistance will change with temperature changing [12].
Advantages
i) Accuracy in small scale of temperature range ii) Good vibration
Disadvantages
i) Limit in small temperature range
3. System overview
3.1 System block diagram
Figure 4: Block diagram of entire system
Figure 5: Block diagram of remote control
Figure 6:Block diagram of sensors unit
Figure 7: Block diagram of alarm unit
3.2 Behavior of Home security system
System
Function
Remote control
- Arm and disarmed the system
-Turn off the alarm that have been trigger
-Control the zone either on or off individually
-Control the zone either active or deactivate for zone checking
-Password setting
-Return the start up point
Sensors unit
-Sent the signal to alarm unit when any of sensor have being triggered
- Sent the signal to alarm unit for status checking purpose when no sensors have being triggered
Alarm unit
-indicate system that either armed or disarmed and zone either on or off which set by remote control
-process the status checking and show a faulty zone by using LED
-activate the alarm when any of the sensors have been triggered or any failure of zone detected
Table 1: Function of entire system
3.3 Motion Detector Circuit
Passive infrared motion detector technology is being used in the circuit. It normally made by crystalline material that will generate a surface electric charge when exposed to heat in form of infrared radiation. The output signal waveform from sensor will show that for motion in one direction, first a positive, then zero and finally a negative transition results like figure above. Meanwhile, if motion is detected from another direction will create the waveform that first a negative, then zero and finally a positive transition. Table 2 below is the average output voltage of passive infrared motion sensor in the range of 6 meters:
Distance
Voltage
Meter (m)
VAVG
0
2.968V
0.5
3.093V
1.0
3.134V
1.5
3.231V
2.0
3.350V
2.5
3.457V
3.0
3.344V
3.5
3.193V
4.0
3.021V
4.5
2.744V
5.0
2.627V
5.5
2.427V
6.0
2.173V
Table 2: Average output voltage of PIR motion sensor
3.4 Heat detector circuit
Thermistor heat detector technology is being use in the circuit. The function of thermistor is detecting the heat where it very sensitive to the temperature. As temperature increasing, the resistance will decrease then the voltage will increase. Table 3 below is the average output voltage of thermistor heat detector sensor from 28 degree Celsius to 80 degree Celsius:
Temperature
Voltage
Celsius(°C)
VAVG
28
0.505V
30
0.550V
32
0.609V
38
0.678V
40
0.700V
42
0.726V
50
1.051V
60
1.357V
70
1.675V
80
1.886V
Table 3: Average output voltage of thermistor heat sensor
4.0 Conclusion
Home security system is a combination of hardware and software element that can alert the use when fire accident or crime happened. In this project, 2 sensors have being use to detect the motion and heat. After done the experiment and testing, the 2 sensors able to detect the motion in the range of 3 meters and detect the heat which temperature limit set to 40 Celsius and then it will trigger on to sent the signal to PIC microcontroller in order to allow the user take the next actions. This project only allow to operate by log in the correct default password in remote control and function of reset password in remote control also allow in order to secured the system from other people. All the information that entered by keypad able to display in LCD display and LED as indicator to let the user which alarm or zone is activated.
