Thesis Abstract

Abstract
Metal detectors are widely used in various fields such as security, mining, and treasure hunting. This research project focuses on designing and constructing a handheld magnetic metal detector for the purpose of detecting landmines, metal treasures, and ores by miners. The device utilizes a combination of electromagnetic induction and magnetic field sensing techniques to detect metallic objects buried underground. The proposed metal detector consists of several key components including a search coil, control unit, power source, and audio/visual indicator. The search coil serves as the primary sensing element that generates an electromagnetic field when energized by the control unit. When the coil passes over a metallic object, it induces eddy currents in the metal which in turn creates a secondary magnetic field. This change in magnetic field is detected by the sensor in the control unit, triggering an alert to the user through the audio/visual indicator. To enhance the detection capabilities of the device, advanced signal processing algorithms are implemented in the control unit to filter out background noise and interference. This allows for improved sensitivity and accuracy in identifying metallic targets of interest. Additionally, the metal detector is equipped with adjustable sensitivity settings to accommodate different types of metal objects and varying depths in the ground. The handheld metal detector is designed to be lightweight, portable, and easy to operate, making it suitable for use in various environments. For landmine detection, the device can help humanitarian demining teams locate buried explosives more efficiently and safely. In the mining industry, the metal detector can assist miners in identifying valuable ore deposits hidden underground, thereby increasing productivity and reducing extraction costs. Treasure hunters can also benefit from this device by uncovering buried artifacts and precious metals with greater ease. Overall, the handheld magnetic metal detector developed in this project offers a versatile and effective solution for detecting metallic objects in different scenarios. By combining electromagnetic induction and magnetic field sensing technologies, the device provides reliable performance and user-friendly operation. Future enhancements may include integrating wireless connectivity for data logging and remote monitoring, as well as improving the durability and ruggedness of the device for long-term use in challenging environments.

Thesis Overview

INTRODUCTION

1.1 Background Information

In the beginning metal detectors, couldn’t pick up everything deeper than one inch down. This time passes and inventors learn more, the capabilities of the detector have greatly improved, on July 2, 1881, America president, James Garfield was shot in the chest and the bullet was left behind. Alexander Graham Bell tried using one of the first original metal detectors, in order to help locate the bullet. Alexander Graham Bell was not able to locate the fatal bullet that was left behind. There was a revamped version of the one that Alexander Graham Bell used to help James Garfield with. Metal detectors have many uses, they are used medically to find metal in human body (Alexander Graham Bell 1881) Metal detectors are also use in the process of detecting land mines and prospectors also were very glad to use the invention. Constructions, is yet another field in which the metal detector is very welcome (Errata, 1994). In this case they use the metal detectors ability to search out steel reinforcement beams pipes and wires. Archaeologist, also use a metal detector to help in the findings of coin; and artifacts. Many people have become interested in the use of metal detectors, over the last few decades. A metal detector is an electronic instrument which detects the presence of metal nearby (Alexander Graham Bell, 1881). Metal detectors are useful for finding metal inclusion hidden within object s, buried underground. They often consist of an handheld unit with a sensor probe which can be swept over the ground for other objects. If the sensor comes near a piece of metal this is indicated by a changing tone in earphones, or a needle moving on an indicator. Usually the device gives some indication of distance; the closer the metal is, the higher the tone in the earphones or the higher the needle goes. Another common type of stationary “walk through” metal detector used for screening at access point in prison, courthouses, and airport to detect concealed metal weapon on a person’s body(Graves Metal, 1998). A magnetic metal detector is an electronic device that that uses magnetic sensor to find metal objects around, it is made of an oscillator that produces a.c that passes though coil which creates alternating magnetic field.

1.2     Problem Statement

We have experienced high rate of crime and corruption in recent years. This has call for more sensitive, efficient and dependable metallic detectors in some areas such as banks, seaports, airports, schools, shopping halls, prisons etc.

1.3   Aim and Objectives

To design and construct an handheld magnetic metal detector for the purpose of detecting, landmines, metal treasures, ore by miners etc.                                  

The objective of this project comprises the following:

•   To design and construct a more reliable, sensitive and dependable metal detector.

•   To improve on previous work done on metal detectors.

•   To design a metal detector suitable to checkmate the recent security challenges in NDA and country at large.

• Also use in the prison by prison warders and various checkpoints by the military and paramilitary for search purpose                                                                

1.4 Justification

This project is significant in that it is being carried out at a period of unprecedented use of internet and other telecommunication networks in Nigeria especially in Nigerian Defence Academy

1.5 Motivation

This project was put up, due to various issues of urban menace, the present security instabilities and insurgency situation of our country (Nigeria), in areas like club centres, recreation areas, amusement parks, bank, hospitals, etc by some unlawful citizens, who are being aided and sponsored by some set of highly placed persons usually known as (godfathers).

1.5Significance of Study

This project is significant in that it is being carried out at a period of unprecedented uses of internet and other telecommunication networks in Nigeria especially in the military.

1.6 SCOPE OF THE PROJECT

This project and implementation report covers the design and the construction of a security metal detector (handheld) with indicator that will be ringing when metal is being detected.