AUTOMATED LIQUID FUEL LEVEL SENSING AND CONTROLLING USING MICROCONTROLLER

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1 AUTOMATED LIQUID FUEL LEVEL SENSING AND CONTROLLING USING MICROCONTROLLER Abdelrasoul jabar Alzubaidi 1, Osman Ibrahim Alaga 2 1 Sudan university of science and technology- Engineering Collage-School of electronics- Khartoum- Sudan. rasoul46@live.com 2Electrical Engineering Department,Jordanian Sudanese College of Science and Technology, Khartoum- Sudan. Uosiagha@yahoo.comU Abstract :. This paper deals with the implementation of a microcontrollers for sensing and controlling the liquid fuel level. The purposed work is to automate the process of fuel pumping in a tank storage system and has the ability to detect the level of fuel in a tank, and accordingly display the status on the LCD screen digitally and raises an alarm. This application will provide an improvement on existing fuel level controllers by its use of calibrated circuit to indicate the liquid level and use of DC instead of AC power thereby eliminating the risk of electrocution. Keywords: Microcontroller Fuel level sensors, Ultrasonic sensors, LCD Display. I. INTRODUCTION A rapid advance in technology has made a variety of level sensing, monitoring and control capabilities available. A large number of physical principles are adopted for realizing liquid level sensors. Generally the choice of most suitable level sensor for specific application is based on following requirements: (i) measurement range (ii) resolution (iii) accuracy (iv) characteristics of liquid and of (v) environment.the great interest is focused on last two requirements and in particular developing reliable and safe sensors for hazardous and explosive liquids and environments. It is proposed to model a level sensor using AVR Microcontroller that can be used to sense the fuel level digitally. Consequently which will indicate the fuel level in the tank and display LOW, MEDIUM or HIGH using LCD display and also to prevent overflow and avoid wastage of fuels by buzzing when the tank is about to brim. Basically there are three types of fuels: solid, liquid and gaseous fuels. This work is designed for liquid fuels which are further of two types: petroleum and diesel. This work is suitable for both types of liquid fuels. Petroleum is categorized as regular and premium. Premium is more superior to regular petroleum in terms of octane rating. The octane rating is the fuel's resistance to spontaneous combustion under compression. The higher the octane rating, the more compression it takes to make the fuel spontaneously ignites. So in order to measure the exact amount of fuel in a tank we need to use microcontroller. An AVR microcontroller is used to automate the process of fuel pumping in a tank storage system. This Design have the ability to detect and accordingly display level of the fuel on an LCD screen and buzz as per the requirement. A UV sensors is used to detect fuel level. The use of DC power instead of AC will eliminate the risk of electrocution. The main objective of this paper is to provide an overview of a microcontroller based

2 design for fuel level control to carryout the following: Design and development of an AVR microcontroller based liquid level sensor and better understanding of its operation, programming, and control. Perform theoretical and experimental evaluation on the microcontroller in order to develop an understanding of the microcontrollers. II. SYSTEM DESIGN AND COMPONENTS For this experiment an 8 bit AVR microcontroller is used as a processor, an ultrasonic sensor as an input device for fuel tank, fuel pump, LCD screen and buzzer for display of output. An AVR programming software is used to write into AVR microcontroller memory. UV sensor senses liquid level by sending a signal and receiving the reflected signal. Level of the liquid is calculated using equation (1) below: Distance = speed * time.. (1) Where, speed is of ultrasonic sensor. It generates high frequency sound wave (340 m/s) and evaluate the echo which is received back by the sensor. The sensor calculates the time interval between sending the signal and receiving the echo to determine the distance of liquid fuel. Then the microcontroller processes and displays the result on LCD screen. An alarm is raised when fuel level increases the desired level. Figure (1) below shows how input-output devices are connected to the microcontroller. Ultrasonic Sensor Microcontroller Circuit Power Supply Unit LCD BUZZER PUMP Figure.(1).Block diagram of the circuit design The technique of fuel level monitoring and controlling system concentrated with some basic parts which are softly aggregated together in the proposed method. The basic descriptions of the hardware components are described below: a. Ultrasonic Sensors : Ultrasonic sensors (also known as transceivers when they both send and receive, but more generally called transducers) work on a principle similar to radar or sonar which evaluates attributes of a target by interpreting the echoes from radio or sound waves respectively.

3 Ultrasonic sensors generate high frequency sound waves and evaluate the echo which is received back by the sensor. Sensors calculate the time interval between sending the signal and receiving the echo to determine the distance to an object. An understanding of radiation patterns and the target's effect on echoes is essential for evaluating candidate sensors in terms of frequency variations, accuracy and resolution, target range, effective beam angle, and the influence of ambient temperature variations on sensor performance. Ultrasonic transducers are available in two types piezoelectric transducers and magnetostrictive transducers. Both transducer designs produce ultrasonic activity by rapidly oscillating the ultrasonic diaphragm to which they are mounted. However, each design performs this action differently Piezoelectric transducers are more power efficient compared to magnetostrictive transducers. Piezoelectric transducer is used in this work because of its power efficiency. Piezoelectric transducers are bonded to the ultrasonic diaphragm with a combination of high-temperature epoxy, and a metallurgic bond usually composed of a welded and threaded stud. Magnetostrictive transducers are bonded using vacuum brazing of the transducer base to the ultrasonic diaphragm. UV sensors work on the principle of ultra violet detection. This technology can be used for measuring wind speed and direction (anemometer), tank or channel level, and speed through air or water. For measuring speed or direction a device uses multiple detectors and calculates the speed from the relative distances to particulates in the air or water. To measure tank or channel level, the sensor measures the distance to the surface of the fluid. Further applications include: humidifiers, sonar, medical, ultrasonography, burglar alarms and nondestructive testing. b. AVR Microcontroller : The AVR (Advance Virtual RISC) is a modified Harvard architecture 8-bit RISC single chip microcontroller. The AVR was one of the first microcontroller families to use on-chip flash memory for program storage, as opposed to one-time programmable ROM, EPROM, or EEPROM. A reference manual is used as a guide for the instructions, programming and interfacing of the microcontroller. AVR features are discussed below. i). AVR feature includes Internal data EEPROM up to 4 kb. They are about 4 times faster than PICs and consume less power. Internal SRAM up to 16 kb (32 kb on XMega). 8-bit and 16-bit timers. PWM output (some devices have an enhanced PWM peripheral which includes a dead-time generator). Input capture that record a time stamp triggered by a signal edge. 10 or 12-bit A/D converters, with multiplex of up to 16 channels. 12-bit D/A converters. LCD controller support. Low-voltage devices operating down to 1.8 V (to 0.7 V for parts with built-in DC DC up converter) Pico Power devices c. LCD Screen : LCD (liquid crystal display) is the technology used for displays in notebook and other smaller computers. Like lightemitting diode (LED) and gas-plasma technologies, LCDs allow displays to be much thinner than cathode ray tube (CRT) technology. LCDs consume much less power than LED and gas display displays because they work on the principle of blocking light rather than emitting it. The

4 LCD screen is more energy efficient and can be disposed of more safely than a CRT. Its low electrical power consumption enables it to be used in battery- powered electronic equipment. A 16*2 LCD is used in the design. d. Buzzer; A Buzzer or beeper is an audio signaling device which may be electromechanical, mechanical, or piezoelectric. A typical use of buzzers and beepers includes alarm devices, timers and confirmation of user input such as a mouse click or keystroke. e. Fuel pump : A pump is used for filling the fuel tank with fuel. IV. ALGORITHM The microcontroller algorithm is based on sensing the fuel level, displaying the level on the LCD, and accordingly controls the fuel pump. The sensed fuel level gets converted into digital format by the ADC in the microcontroller. The program in the microcontroller performs the calculations and display the results on the screen of the LCD. Bascom programming language is used in programming the microcontroller and Pony Prog proram is used to download the program from the computer into the microcontroller. The algorithm for the microcontroller is : III. CALCULATIONS Pipe from which petrol enters is of the cubic shape Its height=10 inch = 0.254m = 25.4cm Its width=15 inch = 0.384m = 38.4cm Its length=22 inch = 0.558m = 55.8cm Volume = L*B*H = cubic meter = 51 liters Flow rate of petrol in a petrol pump is = 37.8 liters per min Let s take Height of 1cm Other values are Length = 55.8cm Width = 38.4cm Volume=L*B*H= cubic meters = 2.12 liters. It means that it will insert 2.12 liters for 1 cm height. 1 sec will have = 0.60 liters Hence, 2.12 liters = 3.3 seconds. Now we have for 37.8 liters per min = 79 seconds. Therefore equation (2) gives the time for (x cm.) height filling. Time for x cm height tank is filled = 3.3 * Time for petrol inlet pipe is ON in seconds (2) Start Initialization :.. Configure port B of the microcontroller as output port... Configure Port A as Input for the ADC. Display start operation on the screen of the LCD. Activate the fuel pump. Ultrasonic sensing : Activate the Ultrasonic sensor..input the echo voltage to the ADC...Transform the echo voltage into digital format. Apply the formula for calculating the fuel level. Display the fuel level on the screen of the LCD... If fuel level is close to FULL then Issue a buzzer alarm Stop the fuel pump Go to ultrasonic sensing. End

5 V. CONCLUSION All the natural resources are important basic needs for all living beings. Our intention of this research work was to establish a flexible, economical and easy configurable system which can solve our liquid losing problem. We are using a low cost AVR microcontroller in this system which is the key point to reduce cost. We have successfully experiment the system and therefore proposed an AVR Microcontroller based liquid level monitoring and controlling. Thus we could have substantial benefit from this research work for efficient management of liquid natural resources. This research will provide an efficient way for managing and monitoring large as well small fuel storage systems. [9] G.Betta, A.Pietrosanto and A.Scaglione: A digital level transducer based on optical fiber,imtc95,boston,usa,1995 and to appear on IEEE Transactions on Instrumentation and Measurement April REFERENCES : [1] T.G.Giallorenzi et al, sensors challenge the competition, IEEE Spectrum,2006. [2] Sensor technology edited by Jon S. Wilson,Prentice hall [3] Handbook of Modern Sensors : Physics,Designs, and Applicaions,3rd edition by Jacob Fraden. [4] M.H. Rashid, Power Electronics, Circuits,Devices, and Applications, Englewood Cliffs: Prentice Hall, [5] Ultrasonic Sensor Application Manual Murata Manufacturing Co., Ltd copyright [6] V. Matz, M. Kreidl, R. Šmíd. Classification of ultrasonic signals. [7] Atmega 32 microcontroller Data Sheet. [8] Paul A. Shirley. Nov "An Introduction to Ultrasonic Sensing," Sensors, Vol. 6, No. 11.