The Smart Metal Detector

The Smart alloylic element sightorThis suffer is the combination of hardware and software increase. With the aid of the micro- chastenessler, this alloy demodulator terminate encounter more useful function. This system consists of 3 main parts of hardwareThe construction of smart admixture sensing element required the gathering of information/ acquaintance/ c one timepts of obstacle sensor, LCD Display, H-Bridge DC motor driver, flick micro-controller, coat sensor technology and so on. Besides that, some knowledge in software part PIC convention language and opposite useful software MPLAB, Protel XP, and multisim are also needed.Nowadays, Metal detectors tolerate work a rattling common staple in todays society and widely employ in man live in a range of usage from leisure to work and also safety purpose. For guard purpose, Metal detector that use in airport to ensure that there is no dangerous arm such as knives, guns or any metallic element objects that could be apply as weapons has been brought along by terrorist into the airplane. In technical area, people used metal detector to search for the underground pipe or cable before digging in walls and floors. Besides that, many people enjoy in discovering surreptitious treasure or valuable metal like gold and silver by using metal detector.Metal detector products are available in market place. It has many types of metal detectors are sold which used in different area. However, many of them have the following disadvantagesExpensiveThe prices of metal detectors are very expensive. Although the more(prenominal) expensive metal detector has higher transaction and functionality, usually we dont need so much of the function. The particular function that we dont need leave alone be wasted. So the prices of metal detector products that sold in market wouldnt be afford by everyone.Manually controlled metal detectorMany of the metal detectors are manually controlled by human where user s are required to handle it and walk around to detect the underground metal. This is very exhausted and tired work.Based on these two disadvantages, users need a low cost and have basal function of mobility metal detector. The smart metal detector is a device that used to detect metallic stuff such as coins, gold and other metal items. It bay window chance on and interpolate the direction of movement in certain situation to scan the underground metal. It allow take a U turn when it reached the desired distance which already set inside the microcontroller and continue move in another track. It will avoid the obstacle with the help of sensor. When it detects a metal, it will beep on qui vive to argueize user.2.0 Statement of AimsBelow are the aims that targeted to achieve in the Smart metal detector startAutomatic movementIn this section, the concept of relationship between H-Bridge driver and DC motors are utilize into the excogitate. The H-Bridge driver is a electrical circuit that used to control the direction of DC motors with the help of micro-controller.Obstacle schemeWhen the device has detected an obstacle blocking in front of the metal detector, it will avoid the obstacle automatically by changing its movement direction to prevent collision happened.Micro-controller applicationA micro-controller is used to become the main brain of the mobile metal detector. The main purpose of the micro-controller is used to give educational activity to control all the function of the metal detection. alert beep when detect metalWhen the metal detector has been detected underground metal, the buzzer will beep on to inform users that some metal elements have been detected.LCD display indicationAll the status and marrow from the metal detector are indicating in the LCD display. For example, the message of Metal Found will be shown in LCD when the metal detector has been detected metal element.3.0 ObjectiveThe main objective of this advise is to develop a Smart Metal Detector into more automation area. With the automation of metal detector, this concept will be contributed to the real sustenance application.The sub-objectives of this project will be elaborate belowTo apply the electric and electronic knowledge that I have learned into the real application scope of operation.To provide a low cost metal detector for general metal detection purpose.To learn the skill of writing software in PIC Assembly language.To learn the skill of debugging the software problems or bugs.To learn how to work followed the planned schedule, as well as the Gantt Chart.4.0 Literature ReviewThe first person that invented the first crude metal detector in 1881 was black lovage Graham Bell. After that, the metal detector concept has been kept on improving to become more advance and applicable in various areas.Basically, there are three technologies used in metal detectors. These three technologies are I. Very Low Frequency (VLF) TechnologyII. Pulse Induct ion (PI) TechnologyIII. Beat-Frequency cps (BFO) TechnologyVLF is known as induction balance and it is also the near popular metal detector technology used nowadays. at that place are two distinct whorls that used in a VLF metal detector, transmitter coil and receiver coil. The transmitter coil is the outer coil closed circuit which is coiled with fit out. Electricity is being sent along the wire and creates the electrocharismatic battlefield. The receiver coil is the national coil loop which is also coiled with another wire. The receiver coil acts as an antenna to adjourn up and amplify the frequencies which come from the target metallic objects in the ground.The metal detector has the ability to visit approximately the deeper of the targeted buried object. This can be done by determine the strength of the magnetic field that the object generates. The concept is very simple The stronger magnetic field will be detected if the metal detector is closer to the surface of the targeted object. Alternately, the further the object away from the metal detector, the weaker the magnetic field will be detected.The metal detector also can differential the types of metals. It is relied on a phenomenon called as variant open frameing. The differences in timing between the frequencies of transmitter coil and the targeted object is called phase shift. For example, an object with high inductor will have a larger phase shift because it takes longer eon to alter its magnetic field. However, an object with high resistance will have a small phase shift. The phase shift concept provided VLF establish metal detector has the capability called discrimination. The metal detector used a pair of electronic circuits called phase demodulators to correspond the phase shift of target object with the average of a particular type of metal to examine the metal class of the target object. The detector will thusly notifies user with audible tone or visual indicator of what class of the metal is most promising to be. The phase shift concept also allowed user to filter out (discriminate) the unwanted object preceding(prenominal) a certain phase-shift level.Pulse Induction (PI) technology is a less common form of the metal detector. PI metal detector uses only single coil as both transmitter and receiver, or using 2 or 3 coils work together. The metal detector sends powerful, short split seconds of current by dint of a coil of wire. This cause each pulse generates a brief magnetic field. The magnetic field will reverse polarity and collapses very suddenly after the pulse ends and causing a crafty electrical spike. After the spikes, a current called reflected pulse will run through another coil and this process will keep on repeating in very short time. The PI ground metal detector works like echoes If the metal detector is over a metallic object, an diametral magnetic field will create by the pulse in the object. After the collapsing of the pulses magne tic field, the reflected pulse will be generated, and thus the magnetic field of the object cause it take longer time for the reflected pulse to disappear absolutely.A sample circuit is set to monitor the length of the reflected pulse. The circuit can determine if another magnetic field has caused the reflected pulse decay in longer time (usually a few microseconds) than normal, it will suspected that some metallic object is being interfering with it. Usually the try out circuit is connected to a device called integrator. This integrator can read the received note from sampling circuit amplifies and converts the signal to direct current (DC). This DCs voltage is connected to an audio circuit which used to indicate the user that targeted object has been detected. This function is almost similar to the VLF based metal detector.PI based metal detector is not as good as VLF based metal detector in discrimination due to the limitation of reflected pulse length of various metals are di fficult to separated. However, PI detector is very useful to detect object in areas that have highly conductive material such as salt-water exploration. In addition, PI detector has the advantage that can detect metal much deeper in the ground than other systems.Beat- oftenness oscillator (BFO) technology is the most basic way that used to detect metal. There are 2 coils of wire in BFO detector. A large coil is in the serarch head and the smaller coil is located inside the control box. Both coils are connected to an oscillator that generates thousands of pulses of current per second. The frequency of the pulses is moderately offset between two coils. When the search head passes over a metal object, the objects magnetic field will interferes with the frequency of the radio waves which generated by the search head coil. After that, the frequency will deviates from the frequency of the coil in the control box and cause the audible beats change in while and tone. The BFO detector is sold in low cost compare to other technologies detector, however, the accuracy and the level of control are not provided.Although there are 3 different of technologies used in metal detector, the basic concept of metal detector can be simplify as using the coil of wire to detect the magnetic field of the underground metal. Hence send a feedback signal to main circuit or micro-controller to process it.Those metal detectors have various types of function and advance performance however most of them are manually controlled by human. This project is basically applied the technology of metal detector into a more automation field instead of using human control, but not improving of the performance of any market products.5.0 Design MethodologyIn order to wind up the project in time, I have separated the whole project circulate into several parts. The project development progress is shown in the flowchart formPlanningLiterature researchLiterature Review in background knowledge of metal de tector.Information of hardware/components gatheringSoftware learningComponents purchasingHardware constructing (Prototyping)Testing/Experiments authorship software (Programming)Modify PrototypesSoftware improvingTestingTroubleshooting/DebuggingFinal AssemblingProject Completed6.0 research and Competitive AnalysisThe hardware part of smart metal detector consists of inputs and outputs. The input parts include obstacle sensor and metal detector circuit. The output parts included H-bridge driver, DC motors and buzzer. A micro-controller is used to interconnect and control the operations among the hardware components. It receives input signals from different inputs and gives the teaching to the outputs based on the situation. The micro-controller will only execute the program that stored inside the memory.Micro-controller works as the brain of the Smart Metal detector. It gets the feedback signal from the sensors/detectors then sending signal to control the condition of the H-Bridge d river and turn on the buzzer once metal is detected.Obstacle Sensor to detect obstacle that blocking in front of the mobile detector to avoid collision happened.Metal detector used to detect the underground metal/mine. The metal detector circuit is uses the coil/inductor to detect the magnetic field of the underground metal. When the coil/inductor cuts the magnetic field of the targeted metal, it will send a feedback signal to the micro-controller.LCD Display can have a better looks and more powerful in showing message instead of using LEDs or Seven-Segments display. It displays the message in the form of alphabet or numbers. So, user will have a better judgment in reading the alphabet message compared to just light on some LEDs.Buzzer/Alarm acts an alarm to warn/inform user that something has happened to the metal detector such as mine has been detected.H-Bridge driver and DC motors used to control the direction of DC motors for different condition such as move forward, stop movin g and turning. The DC motors are used to rotate the wheels of the mobile metal detector.8.0 Software prevail ChartThe programming code is written to interconnect the input hardware and the output hardware. The received signal form inputs will be process in the microcontroller and thus send out the react instruction to the output parts. The PIC assembly language is used in this project.The programs of the basically project can be separated into 3 main partsMain routine of moving.Obstacle avoidance.Metal detected.The estimated cost of this project is to prepare a fund which enables us to control the project expenses. For this project, a sum of RM 615 will be allocated to fund the entire project including the hardware and software parts.The cost of the project can be trim to a certain amount by doing market research and comparing the cost among the vendors. In addition, compare different type of metal detector and obstacle sensor also needed to reduce the project cost. Another altern ative is to get second-hand or used goods in order to minimize the expenditure.Besides this, chance(a) wages must also take into consideration. Considering 400 hours will be utilized to accomplish this project and RM 5 per hour will be paid. Yet another RM 150 is allocated to fund the resources fee such as the electricity and petrol usage. Hence, the overhead cost for this entire project will be supercharged at RM 2765.11.0 Risk Assessment and ManagementTo complete this project, a few risks that might affect the progress of the project have been drawn out as prevention is better than cure. If there is no other alternative plan has been made or planned now, then it will definitely leave a bad impact to us if this risk does happen. Firstly, in order to make this project a success, intensive learning of assembly language through reference book and Subject EN0318 Embedded Systems Advanced digital System Design is crucial because I am lack in PIC knowledge and it is bare-ass to me a nd it posts a risk to me.12.0 Conclusion and RecommendationNow just a beginning stage of the project, I have provided a clear view of the objectives and aims of metal detector project and i will complete the entire task stated step by step by following the project homework time. My project planning has stated clearly through the Gantt chart as well as the minute path analysis.The entire research and development job has been done throughout this semester but it still in the early stage the final project. Hence, more information from supervisor, reference book and internet needed. I can increase my knowledge level by workout with the research activity and this may help me to hitch up up my project to quality completion.In addition, found that many interested features and ideas can be added on to the project. But the insufficient time, knowledge and financial problems have restricted me to achieve those extra features. However, if possible I will try my best to achieve it.The extra features areMeasuring of the deeper of the underground metal war cry is required to activate the metal detectorRobot arm added to the mobile metal detectorAs a conclusion, this project smart metal detector may give me experience as an equipment and product engineer with excellent technical and management skills with moral values and bring future benefits to me as an engineer.13.0 References1 http//travel.howstuffworks.com/airport-security.htm1 http//www.losttreasure.com/ auction sale/APViewInCat.asp?ID=72 http//inventors.about.com/library/inventors/blmetal_detector.htm3 http//home.howstuffworks.com/metal-detector1.htm4 http//www.microchip.com