User-Controlled Low Power Home Surveillance System

Transcription

1 User-Controlled Low Home Surveillance System Sherin Susan Varghese 1, M.S Godwin Premi 2 1,2 Department of ETCE, Sathyabama University, Chennai Abstract This paper develops a user-controlled low power home surveillance system with the help of low power sensor groups. The system helps to avoid unnecessary wastage of power and shortcomings of memory conditions. It consists of two sensor groups; alert sensor group which is placed outdoor near doors and windows and detection sensor group which is placed indoor. The alert sensor group senses when an intruder passes through and wakes up the MCU in sleep mode. This activated MCU provides power supply for detection sensor group. When the detection sensor group detects the presence of intruder, the signals will be given to the MCU. It will turn on the web camera to capture images and upload them by means of web server through Internet. Only user can control the entire surveillance system by establishing a call through GSM. In addition to it, this system helps to monitor the household activities in real time from anywhere. Keywords Home Embedded surveillance, Low-power states, Motion detection, PIR sensor, Ultrasonic sensor, Usercontrolled video surveillance. I. INTRODUCTION Today s world is suffering from the extreme presence of thieves and burglaries which affect the security and safety of various fields like home surveillance, industries, offices, banks etc. A home security and surveillance system has become an essential part of any modern automated home. The basic design of a security system begins with analyzing the needs of the inhabitants, surveying existing technology and hardware, reviewing system costs and power consumption, considering monitoring choices, and finally planning the installation. The existing surveillance systems are continuously monitoring and functioning so that they consume large amount of power. This leads to unnecessary wastage of power and also unwanted memory conditions. Standby electricity leads to the major contribution to the power consumption. According to the statistics, around 3 to 12% of residential electricity usage is due to standby power [11]. It varies with countries. Many governments have begun large programs, like Energy Star Program and 1- Watt Plan, to reduce standby power in order to save energy. In this paper, the power efficiency of the home surveillance system can be improved by the proper control and implementation of the system by both hardware and software. The alert sensor group consuming ultra low power consists of a group of Pyroelectric Infrared (PIR) sensors and pressure sensors [1]. 412 These sensors are always kept on to sense the presence of intruder. Whenever the intruder enters the sensing area, the alert sensor group gives signals to MCU and wakes up the sleeping MCU. MCU activates the detection sensor group which consists of a group of PIR sensors and ultrasonic sensors. According to the signals received from the detection sensor group, MCU turns on the web camera to capture images and upload them in the webpage. The user controls the entire surveillance system by establishing a call. Also, the system can be kept in a surveillance mode which provides the real time monitoring of the household activities. Since the conventional surveillance systems consume large amount of power, it is not feasible to use the existing system. The proposed system avoids unnecessary power consumption and unwanted image/video storage by using ultra low alert power sensor group. The system can also be used to monitor where any authorized persons are allowed to enter the house or where sick or elder people are staying inside the house. Also, the system can be used in banks, offices etc. The rest of this paper is organized as follows. System architecture is given in Section II. Sensor segments are explained in Section III and the software modules in Section IV. Section V contains the implementation results and the conclusion in Section VI. II. SYSTEM ARCHITECTURE This paper proposes the development and implementation of a low power home surveillance system with the help of low power sensors and that can be controlled by the user. By the appropriate implementation of indoor and outdoor sensor groups, a low power home surveillance system can be developed. Figure 1 shows the system architecture of user-controlled low power home surveillance system. It is divided into two sections; User and Home section. A. User Section The user section refers to the user or the house owner who holds a mobile phone or similar gadgets to control the home surveillance system from anywhere.only the user can control the entire surveillance system and he/she can see the recorded videos through Internet.

2 Figure 1: User-controlled low power home surveillance system B. Home Section This section refers to the home surveillance system. The various parts are as follows. Microcontroller Unit: The entire surveillance system is controlled by the PIC microcontroller. It is an 8-bit microcontroller which offers high performance and low power consumption. GSM modem: Global System for Mobile Communication (GSM) is the most popular standard for mobile phone in the world.gsm modem is just like a mobile phone. It receives the data which is sent by the user through GSM. It operates in the automatic answer mode. DTMF decoder: Dual tone multi frequency decoder is used to decode the data received by the modem and convert it to binary to be used as an input to the MCU. Alert sensor group: It is placed outdoor near doors and windows. This sensor group is always kept on to alert the presence of intruder. It consists of PIR sensors and pressure sensors, both consume only very less amount of power in terms of mw during standby condition. Detection sensor group: It is placed indoor and will turn on only when the alert sensor group senses the presence of intruder. It consists of PIR sensors and ultrasonic sensors to detect the presence of intruders inside the house. The detection sensor group is used along with the alert sensor group in order to confirm the presence of intruder in the alert state. Figure 2 shows the placement of sensors in the detection state [1]. Figure 2: Sensor placement in detection state Web camera: It is the surveillance camera that helps to capture the videos or images and upload them by means of web server through Internet. It will be turned on only when the detection sensor group detects the presence of intruder. The surveillance camera can also be used to monitor the household activities in real time from anywhere. PC: The user can see the captured and recorded videos or images through Internet using personal computer, mobile phone or similar type of gadgets. The webpage can be accessed by providing the corresponding IP address. 413

3 III. SENSOR SEGMENTS In order to reduce the power consumption, the alert sensor group uses PIR sensors and pressure sensors.pir is basically made of pyroelectric sensors to develop an electric signal in response to a change in the incident thermal radiation. Every living body emits some low level radiations and the hotter the body, the more is emitted radiation [9]. Commercial PIR sensors typically include two IR-sensitive elements with opposite polarization. When the sensor is idle, both slots detect the same amount of IR, the ambient amount radiated from the room or walls or outdoors. When a warm body like a human or an animal passes by, it first intercepts one half of the PIR sensor which causes a positive differential change between the two halves. When the warm body leaves the sensing area, the reverse happens, whereby the sensor generates a negative differential change. These change pulses are what is detected. Figure 3 shows the output waveform the PIR sensor [3]. In order to shape the field of view of the sensor and to cover much larger area, Fresnel lens is used. Along with pyroelectric sensor, a PIR sensing IC has been used to produce the digital output. But the PIR sensor cannot sense a low speed or heat-insulated object. The ultrasonic sensor module generates square waveform with multiple frequencies. The ultrasonic transducer transforms the voltage waveform into an ultrasonic transmission and the transducer of the receiver transforms the ultrasonic transmission into the voltage waveform. Since the receiver may experience external interference at different frequencies, it is necessary to have proper design and implementation of the hardware components [1]. Table I shows the sensors used in two different sensor groups for the purpose of intruder detection. A single sensor group may have multiple number of each sensor say, three PIR and pressure sensors in a single alert sensor group. It is used for improving the sensing capability of the system. Sensor Groups TABLE I SENSORS USED IN THE SYSTEM Alert Sensor Group Detection Sensor Group PIR sensor Use Use Pressure Sensor Use Not in Use Ultrasonic Sensor Not in Use Use Figure 3: PIR sensor output waveform Thus pressure sensors are also used which are designed by linear potentiometers. The pressure sensors are very thin and placed on the ground [1]. When an intruder invades, the pressure on the linear potentiometer increases the resistance value, and the MCU determines according to the resistance value whether someone is passing through. The detection sensor group uses PIR sensors and ultrasonic sensors. An ultrasonic sensor consists of transmitter and receiver and it transmits ultrasonic waves into the air and detects reflected waves from an object. Ultrasonic waves are sounds which cannot be heard by humans and are normally, frequencies of above 20 KHz. Usually piezoelectric ceramics are utilized as ultrasonic sensors. 414 IV. SOFTWARE MODULE The entire surveillance system is implemented by using a microcontroller. The program required for the specific application should be executed and burned into the MCU. The code is written in ASSEMBLY language and is compiled using MPLAB. MPLAB generates a hex file and is burned into the IC using programmer device. Figure 4 demonstrates the flowchart of the software which helps to visualize the coding steps. At the beginning of the program, the microcontroller is initialized and the ports used are set. Then it waits for 20 seconds to warm up the system. The password known only by the user is given and is checked by the MCU. If the password is correct, keys for either entering into intrusion detection mode or surveillance mode is pressed. If the surveillance mode is opted, then the web camera is directly turned on and the real time monitoring is possible. When the reset key is pressed, the web camera is turned off and it will reset the entire system. If the intrusion detection mode is opted, the alert sensor group is turned on and is waited for the sensing. If the alert sensors detect the presence of intruder, then the detection sensor group is turned on. If the detection sensors also detect the intruder, the web camera is turned on and it will capture the videos or images of intrusion. The user can see the recorded videos or images from anywhere.

4 If the user provides the reset key, then the sensor groups and the web camera will be turned off and the entire surveillance system is reset. a web camera Reset key pressed? Start Initialize the microcontroller Password stored and checked Yes Yes Password correct? Key a or b pressed? No b alert sensor group Alert sensors detected? V. IMPLEMENTATION RESULTS The proposed system is implemented and tested for the desired functionalities. The function of GSM modem is done by using a mobile phone. The system is tested for all the mentioned criteria for optimal performance. Based on several experiments, it is verified that this system can resolve the presence of any warm body within the coverage area and execute subsequent actions. A PIR sensor cannot detect low speed or heat insulated objects. Similarly, if someone walks straight towards a PIR sensor, it will not detect them until they are very close by. In order for the system to work well most of the time, pressure sensor is used along with PIR sensor. Precaution is required if there are pets in the house. There are special lens available or a tape can be put on lower part of the existing lens, so as to avoid detection close to the ground. The placement and subsequent testing of all the sensor modules is a must for the proper functioning of the system. Before the detection of intruder, the alert sensor group is always kept open to sense the presence of intruder outside the house. After the detection of intruder, the detection sensor group and the web camera will also be turned on. Table II shows the power consumption of the sensors in a single sensor group in two different operating states [1]. System State TABLE II POWER CONSUMPTION OF SENSORS Alert State (mw) Detection State (mw) PIR sensor Pressure sensor Turn off the sensor groups and the web camera No detection sensor group Detection sensors detected? Ultrasonic sensor Not in Use Table III shows the comparison of the power consumption between the operation states. This measurement shows that the proposed home surveillance system with the alert state reduces the average power consumption. Figure 4: Software flowchart 415

5 TABLE IIII COMPARISON OF POWER CONSUMPTION BETWEEN THE OPERATION STATES Proposed System Existing System in Alert State in Detection State Average by staying 90% in Alert State and 10% in Detection State 14.8mW 20.19W 2.032W 18W 18W 18W Because of continuing intrusion detection the existing systems consume more power, which is around 18W. In the proposed design, the power consumption has been reduced to W from 18W by staying 90% in the alert state and 10% in the detection state. VI. CONCLUSION In this design, the system operates in two modes; intruder detection mode and surveillance mode. It can be used to detect the presence of intruder by avoiding unnecessary wastage of power and shortcomings of memory conditions and also for real time monitoring. Two sensor groups are used in order to improve the detection reliability. In intruder detection mode, the alert sensor group is always kept open to sense the presence of intruder and send signals to MCU which is usually in sleep mode. According to the signal received, MCU turns on the detection sensor group to detect the presence of intruder inside the house and the detection sensor group gives the feedback signal to the MCU. According to this, the web camera will be turned on and the user can see the captured videos/images from anywhere through Internet. In surveillance mode, the user can monitor the whole household activities in real time. In this security system PIR sensor has been used which is low power, and low cost, have a wide lens range, and are easy to interface with. In order to enhance the sensing reliability of the system, use of more advanced techniques such as probabilistic theories and soft computing is left open for the future. Also in this system, there is no mechanism to alert the house owner. Thus the system can be developed to make an alert call to the user in case of any intruders. REFERENCES [1] Ying-Wen Bai, Zi-Li Xie and Zong-Han Li, Design And Implementation Of a Home Embedded Surveillance System with Ultra Low Alert, IEEE Transactions on Consumer Electronics, February 2011, Vol.57. No.1, pp [2] Ying-Wen Bai, Zong-Han Li and Zi-Li Xie, Enhancement of the Complement of an Embedded Surveillance System with PIR Sensors and Ultrasonic Sensors, The 14th IEEE International Symposium on Consumer Electronics, Braunschweig, Germany, June 07-10, 2010, pp. 1-6 [3] Zamshed, Masudul, Muhammad and Rumana Aktar, Design and Implementation of Pyroelectric Infrared Sensor Based Security System Using Microcontroller, IEEE Students Technology Symposium, IIT Kharagpur, January 2011,pp.1-5 [4] Yu-Kang Lo, Shang-Chin Yen, and Chung-Yi Lin, A High- Efficiency AC-to-DC Adaptor with a Low Standby, IEEE Transactions on Industrial Electronics, Feb. 2008, pp [5] Cheng-Hung Tsai, Ying-Wen Bai, Wang Hao-Yuan and Ming-Bo Lin, Design and Implementation of a Socket with Low Standby, IEEE Transactions on Consumer Electronics, August 2009, Vol. 55, No.3, pp [6] Ying-Wen Bai, Jui-Po Hsu, Hen Teng and Hsing-Eng Lin, Design and implementation of an embedded surveillance system with video streaming recording triggered by an infrared sensor circuit, International Symposium on Communications and Information Technologies, Oct. 2007, pp [7] Jun Hou, Chengdong Wu, Zhongjia Yuan, Jiyuan Tan, Qiaoqiao Wang, Yun Zhou, Research of Intelligent Home Security Surveillance System Based on ZigBee, International Symposium on Intelligent Information Technology Application Workshops, Dec. 2008, pp [8] Ying-Wen Bai and Jung-Lu Chen, The Enhancement of Speech Recognition Probability by Homogeneous Majority Voting Mechanism, The International Association of Science and Technology for Development, Signals, and System, Nov. 2004, pp [9] Sneha Nahatkar, Avinash Gaur, Tareek M. Pattewar, Design of a Home Embedded Surveillance System with Pyroelectric Infrared Sensor and Ultra-Low Alert, International Journal Of Advanced Research in Electronics and Communication Engineering, September 2012, Vol.1. No.3, pp [10] Ying-Wen Bai, and Yi-Te Ku, Automatic room light intensity detection and control using a microprocessor and light sensors, IEEE Transactions on Consumer Electronics, Aug. 2008, pp [11] Alan K. Meier, A worldwide review of standby power use in homes," Lawrence Berkeley National Laboratory, Dec. 2001, pp.1-5 [12] A. Meier and W. Huber, Results from the investigations on leaking electricity in the USA, Lawrence Berkeley National Laboratory, California, 1998, pp