ENERGY AWARE SMART HOME AUTOMATION USING ARDUINO AND LABVIEW

Transcription

1 ENERGY AWARE SMART HOME AUTOMATION USING ARDUINO AND LABVIEW Bilal Shaheen, Hamza Khan, Kamil Abbas, Haroon Ur Rashid Abstract In smart homes, information technology is used to control electrical equipment and to converse with the surroundings. The technology is new and is still in the development phase. Smart home automation system is capable of replicating the domestic activities performed on daily basis such as light automation, security of the house, watering system and HVAC (heat, ventilation and air conditioning). The backbone of the system is LabVIEW which provides the complete control in the form of GUI to the end-user. This home automation system is made up of different subsystems, capable of controlling lights around the house, fire and burglar alarm to warn the user and automating different daily routines. By using an internet connection the system can be monitored from all over the world. The prototype of the system has been developed with hardware which is easily available. The prototype of the system not only monitors the power used in the house but also helps in conserving the energy by allowing the user to take full control of the system. Keywords Arduino, labview, smart home, wireless, xbee, zigbee. I. INTRODUCTION Home automation within the recent years has seen much awaited progress. Although the technology is present for quite some time but the recent advancements in the field of signal acquisition and computer manipulations has really helped the process automation industry. Home automation is actually a branch of automation. Automation systems use different kinds of instrument to sense a change or anomaly in the behavior of a plant and then take the necessary action against the detected change. [1] Home automation systems can detect and identify a change and then adjust the light intensity, room temperature or control opening or closing of drapes based on the logic set by the user. These type of features make the home automation smart, because it is making decisions on its own. A user can set manually the number of changes to detect and then take the required action according to the detected change. All these type of features of a home automation system can make the life easier of elderly or those who are physically challenged. The main controller of the home automation system is LabVIEW. The input data from different type of sensors is acquired by Arduino UNO wirelessly with the help of XBee and manipulated in LabVIEW. These connect directly with Arduino UNO which feeds the data to LabVIEW. Different programs are made in LabVIEW which after processing the signal, takes the necessary action by generating a signal at the output. This signal is wirelessly transmitted with the help of an XBee. Another XBee is connected at the load end acting as a router. It receives the signal and triggers the relay circuit to change the state of the load. Fig. 1. Overview of the automation system 20

2 The user gets a graphical interface to interact with different energy loads around the house. This gives complete control over the appliances and the user can turn them on or off or can even schedule time to dim the lights when needed. II. DATA ACQUISITION CARDS Data Acquisition cards acts as a bridge between the real physical world and the digital world. It digitizes the incoming data so that the computer can interpret them. Data Acquisition cards are used to process the physical quantities after they have been transformed into electrical signals by sensing instrument. As newer technology has arrived, Data Acquisition (DAQ) cards with more resolution and input/output ports are available in the market. We can then exploit the displaying and processing capabilities of a PC to further analyze the acquired data. Even though the technology advances has brought in new techniques, the basic structure of every DAQ card is almost the same. Every DAQ contains a signal conditioning circuitry which is comprised of an amplifier and analog to digital converter, input/output ports and microcontroller or microprocessor. Data Acquisition Devices are available in different types, mainly characterized by IO (input/output) ports, sampling rate, resolution and cost. DAQ devices are interfaced with computer in a number of different ways. Most of the DAQ devices are PCI (Peripheral Component Interconnect) and some are designed for mounting in board slots on a computer motherboard. Data Acquisition device interfaces with computer and exploits the processing power and display capabilities of the PC. Usually a software package like NI LABVIEW, NI Measurement Studio, Microsoft Visual C/C++, Visual Basic etc. is used to communicate and manipulate the acquired data. Thus it offers powerful, flexible and economical measurement solution. [2] A. Arduino UNO as DAQ card Arduino UNO is a USB 2.0 and 3.0 compatible device. It is used in multitude of projects. The Arduino UNO is mainly sold as microcontroller board based on ATmega 328 chip. Although the UNO can be used as DAQ card, but its sampling rate is much lower than the NI DAQ cards. The maximum sampling rate that the UNO can achieve is about 5kSamples/sec. The Arduino UNO has an ADC with 10-bit resolution. It communicates through serial port by using its 0 (RX) and 1 (TX) pins. RX pin is used to receive and TX pins is used to transmit the data. Although the number of analog channels is less than that of a NI DAQ card, but it is inexpensive and is easily available. The only downside is the slow sampling rate (30 Samples/sec) and the difficulty in interfacing the Arduino UNO with LabVIEW. [3] III. COMMUNICATION The XBee series 2 chip can be used to implement different types of ZigBee standardized mesh networking The ZigBee mesh network is unsurpassed in low power scenarios. The Xbees are further divided in XBees and Xbees-Pro versions. The only difference between them is that in Pro versions power transmission capacity is higher. The XBee has the ability of routing as it can be used transmit data to a series of other radios to its destination point. So one XBee connected with Arduino UNO and LabVIEW can communicate with the rest of the XBees in the network, each connected with load. It also has the ability to repair the mesh if it finds a missing or broken link. The XBee module connects to a host device through a logic level asynchronous port. Using its serial port XBee can connect to any logic and voltage compatible UART (Universal Asynchronous Receiver Transmitter). Fig. 2. A typical ZigBee network A. API Frame Types In a frame type arrangements there are subarrangements which tell about different types of data that can be send or received from XBee. After looking at first four bytes we can conclude about frame type, starting of a frame and how long that frame is going to be. There are many API frame types designed for XBee but only Remote AT Command Request is discussed, as it fulfills the need of the automation system. B. Remote AT Command Request This mode is used to send commands to the receiving XBee from the coordinator wirelessly. The coordinator should be in API mode and Router in AT mode. One application of this mode is to toggle output of receiving 21

3 XBee from High to Low. It means that we are able to utilize relay circuitry to switch our load end devices over the air. TABLE I. XBEE COMMANDS Byte Example Description 0 0x7E Start byte - Indicate beginning of data time 1 0x00 Length Number of bytes 2 0x10 3 0x17 Frame type 0x17 means this is a AT command request 4 0x52 Frame ID Command sequence number 5 0x00 6 0x13 64-bit Destination Address (Serial 7 0xA2 Number) 8 0x00 MSB is byte 5, LSB is byte x40 0x = Coordinator 10 0x77 0x FFFF = Broadcast 11 0x9C 12 0x xFF Destination Network Address 14 0xFE (Set to 0xFFFE to send a broadcast) 15 0x02 Remote command options (set to 0x02 to apply changes immediately) 16 0x44(D) AT Command Name (Two ASCII 17 0x02(02) characters) 18 0x04 Command Parameter 19 0xF5 Checksum Byte 0 indicates the start of the byte which is 7E and byte 1 and 2 informs about start of byte which is 0 and length of frame which is 16 bytes long respectively. All the numbers written here are in hexadecimal as XBee is programmed to recognize numbers in hexadecimal. Byte 3 gives information about frame type and 17 is an AT command request. Byte 4 is Frame ID which acknowledges whether the other side has received the information or not. The next 8 bytes are to write the serial address of the destination radio. It can be set FFFF to set it as broadcast meaning it will connect to nearest available XBee. The next two bytes are recipient s network address and setting it too FFFE will make it a broadcast. The next byte is about remote command options and setting it to 02 will allow the XBee to make changes immediately. The byte 16 and 17 are going to be the commands send to the remote XBee. The byte 18 contains any parameters to be set. The last 19th byte is checksum which is needed to be accurate otherwise XBee won t perform any function it was assigned to do. It is the sum of bytes after the byte length. [4] IV. LABVIEW The smart home control system has been divided into five parts or subsystems. Each subsystem can be taken out from the network without affecting other subsystems functionality. All these subsystems can be accessed over the internet and desired variation can be achieved. The first subsystem is the external lighting system. It controls all the external lighting around the house. The second subsystem is the internal lighting system which basically controls the ceiling lighting. The third subsystem is the fire alarm system. It detects the presence of fire and warns the user in pre-programmed way. The fourth subsystem is the security unit of the house. It is basically a burglar alarm system. The fifth subsystem is the temperature control of the system and can be adjusted according to user s desire. [5] Fig. 3. Block Diagram of LabVIEW controlled applications A. External Lighting system The external lighting control system developed in LabVIEW uses a light dependent resistor (LDR) to sense the light. The system automatically turns on or off the lights depending upon the readings taken by sensor. On pressing the automatic switch the system automates the light control. A potential divider is set up at the sensors end and a voltage change occurs at the sensors end with the change in intensity of light because LDR s resistance increases with a decrease in light and it decreases as light intensity increases. Thus as potential drop across LDR varies goes below than 3.5v the system turns on the light and when it goes above the particular threshold 22

4 then the lights are turned off. The graphical interface shows a LED which shows the current status of lights that whether they are turned on or off. Moreover the user is also provided with a manual switch to change the status of lights at his or her own will. The system also shows a waveform chart continuously detecting the change in potential drop across the LDR. Moreover a stop switch is present to turn off the system in case of a malfunctioning. waveform chart continuously plots the data being received from the PIR sensor. An emergency stop switch is provided to turn off the system in case of a problem. Fig. 5. Front panel of internal lighting system Fig. 4. Front panel of external lighting system In the back panel the programming for this system is done. Initially the settings for the communication port are done. The Baud rate is kept at Then after initializing the communication port LabVIEW takes input from Arduino UNO card and upon receiving this input compares it with a threshold i.e. if the input is less than 0.3v then a Boolean true occurs but if input is greater than 0.3v then a Boolean false occurs. On receiving a Boolean true serial write is performed. A string is serially written into Arduino and then Arduino acts accordingly. On receiving a Boolean false another string is written which tells Arduino to turn off the system for the particular time being. After this the session is closed. B. Internal Lighting system The internal lighting system uses PIR sensor to detect motion and switch on or off the lights in the room. PIR motion sensor generates a pulse of 3.3v whenever motion is detected. On detection of this pulse the system turns on the lights. Moreover the user is provided with a scheduler to control the time of the day for which the lights should be automatically controlled. Apart from this time the user can manually change the state of lights with the switch provided in the graphical interface. A light indicator is also present which indicates the current state of lights so that the user will be aware that whether the lights are on or off in the particular room. A In the back panel firstly the communication port is initialized. LabVIEW then receives the analog input and then uses a greater than or equal to block to compare the input with a threshold of 3.3v. If input is greater than or equals to 3.3v a Boolean true occurs. When Boolean true is present the output is turned on for a particular time being (as selected by the user) regardless of the input state during that time instance. After that time instance the input is sampled again. Upon receiving a Boolean false again a string is written which tells Arduino to turn off the system for the particular time being. The whole system is placed in a while loop so that the whole system keeps repeating unless the emergency stop is pressed. C. Fire Alarm System The fire alarm system consists of a smoke detector. The smoke detector will send a signal on detection of smoke and then LabVIEW will turn on the alarm to indicate that there is an emergency. Moreover this system will send an or SMS to the user warning him about the situation. Furthermore solenoid valves will be installed in the house and they will turn on to help extinguish the fire. A LED is present on the interface which will start blinking in case of emergency alarming the user visually. In the back panel input is received by LabVIEW and then the input is compared through a greater than or equal to block with a value of 2v. The serial write is placed in a case structure. In case of a Boolean true the system maintains this true state for a particular time instant. During this time instant the alarm will stay on. LabVIEW will send a particular string to Arduino in case of a true and a different string in case of a false. Upon receiving this string Arduino will send corresponding signal to transceivers. 23

5 D. Burglar Alarm This system uses a PIR sensor which will detect motion in case of a forced entry in the house. In detection of entry the sensor will send a pulse of 3.3v. The burglar alarm system in LabVIEW will detect this pulse and turn on the alarm to make the owner aware of the condition. A LED will also start blinking on the main screen indicating the presence of a burglar in the house. This system can also be capable of sending a short message to the user warning him of the condition. E. Temperature Control System LM35 is used as a temperature sensor in the temperature control system. As temperature changes LM35 produces a change in the voltage level which is then used by the LabVIEW to decide whether temperature is increasing or decreasing. Then by comparing the voltage output of sensor to a particular threshold LabVIEW decides whether to turn on the heaters or the air-conditioners. The front panel consists of a thermometer indicating the temperature changes occurring. There are two LEDs one indicating the state of heaters and the other indicating the state of airconditioners. A shutdown switch is present to turn off the system in case of emergency. In the back panel after initialization of communication port input is received. This input is then furthermore compared with a particular threshold as recommended by the user i.e. whether air conditioners should be working at 35C or 4 C and then after comparing, Boolean true or false is created. Upon receiving a true LabVIEW writes a particular string serially to Arduino telling the card to perform a particular function. On receiving a false LabVIEW writes a different string which tells Arduino to turn off the particular output. F. Graphical User Interface The final interface provided to the user will consist of a monitoring screen through which the user will be able to look at the current situation of the system and then will be able to perform the desired tasks. This interface will also provide the monitoring of the entire smart home system. The individual systems mentioned previously are embedded in the final interface. Fig. 6. Final GUI: Monitoring & Control G. Data Logging Fig. 7. Final GUI: Settings Panel LabVIEW also provides the facility of data logging. There will be a excel file associated with every system which will keep a complete log of the working. The data log will consist of the power consumption including the current and voltage consumed by a particular load. At the end of the day the user will be able to see the daily consumption of electricity and then plan the changes accordingly. Moreover this data logging can also indicate the excessive use of a particular item, enabling the user to take necessary action needed. H. Control across the Globe The user will be able to control this system sitting from anywhere in the world through the World Wide Web. The user will be provided with a particular URL. By using this address the user would be able to see the front panel of the system on his screen and would able to control the system. 24

6 Fig. 8. Final GUI: Accessing Front Panel through internet browser V. RESULTS The system was implemented to control the electrical appliances of a room which include light and HVAC systems. The test was conducted for two days after which following results depicted in diagram were recorded. Fig. 9. Energy usage comparison of a Normal House vs Automated House VI. CONCLUSION This paper presents a novel technique to implement a smart home automation system which is both affordable and can be easily replicated with easily available equipment like Arduino UNO and XBees. The automation system is based on a star network and each subsystem communicates with the central control. This eliminates interference and we can take down any subsystem for maintenance without affecting the working of other subsystems in the automation system. The automation system is controlled through LabVIEW software and the accessibility of data over the internet enables the user to access the system from anywhere in the world. REFERENCES [1] ABI Research, 1.5 Million Home Automation Systems Installed in the US This Year, [2] H. Halvorsen, Data Acqusition in LabVIEW, Telemark University College, Porsgrunn, Norway, August [3] M. Margolis, Arduino Cookbook, 1 ed. Sebastopol, CA: O'Reilly & Associates, [4] R. Faludi, Building wireless sensor networks, Beijing: O'Reilly & Associates, [5] B. Hamed, Design & Implementation of Smart House Control Using LabVIEW, vol. 1, issue 6, IJSCE, January [6] Sleman, A.; Alafandi, M.; Moeller, Integration of Wireless Fieldbus and Wired Fieldbus for Health Monitoring ; R.;Consumer Electronics, 2 9. ICCE '09. Digest of Technical Papers International Conference on Jan Page(s):1 2. [7] Van Nguyen, T.; Jin Gook Kim; Deokjai Choi, "ISS: The Interactive Smart home Simulator," Advanced Communication Technology, ICACT th International Conference on, vol.03, no., pp , Feb [8] Standard for a Precision Clock Synchronization Protocol for Networked Measurement and Control Systems, IEEE Std [9] IEEE Standard for local and metropolitan area networks Media Access Control (MAC) Bridges and Virtual Bridged Local Area Networks, IEEE Std 802.1Q [10] LabVIEW User Manual, April 2003 Edition, National Instruments [11] 25