CHAPTER 1 INTRODUCTION

Transcription

1 CHAPTER 1 INTRODUCTION Now a day in places like Afghanistan and Iraq we know that land mines are causing serious threat to the lives of civilians. The mines that are implanted during the wartime may remain undetected for several decades and may suddenly be activated after that. Also during wartime mines implanted by our enemy countries are to be detected and diffused properly in order to save the lives of our soldiers. So we should say that detecting landmines is important for every country today. 1

2 CHAPTER 2 MINE AFFECTED COUNTRIES The countries known to have severe landmine problems are Afghanistan, Bosnia, Cambodia, Ethiopia, Vietnam, Iraq, Kuwait, Laos, Egypt, Eritrea, Chevalier, China. Unfortunately India, Pakistan, Srilanka, Myanmar are in the list of less mine affected countries besides other 100 countries. 2

3 CHAPTER 3 WHAT IS A LAND MINE? The purpose of a landmine is to disable, immobilize or kill. It is an explosive device activated either by a person or vehicle or by command detonated by electric wire or radio signals. Most land mines are laid on just below the surface of ground and are activated by pressure or trip-wire. Usually most of the land mines will contain many metallic parts, which can be made use of in their detection. 3

4 Anti-personal mines claims 70 new victims every day. This weapon is particularly cruel on children whose bodies being smaller and closer to the blast are more likely to sustain serious injury. The severe disabilities and psychological traumas that follow the blast- means these children will have to be looked after for many years. A child injured at the age of 10 will need about 25 critical limbs during there life time. This cost in 3000 Dollars a huge sum to pay in countries where people earn as little as 10 dollar a month.. Between 1979 of 1996 the red crores fitted over 70,000 amputees with critical limbs and the land mine problem in still growing. There for considering these factors the discovery of radar bullet is really a big boost to our world as we launches to 21 st century. 4

5 CHAPTER 4 HOW IS MINE DETECTION CURRENTLY BEING CONDUCTED? PRINCIPLES USED 1. Metal detection 2. Explosive detection 4.1. METAL DETECTION Essentially the two most common components of landmines are metals and explosives. Manufactured mines have casting made from a variety of materials including wood, metals, Plastic metal or other synthetic materials. From the detection standpoint, metal is the easier component to detect. 5

6 Metal detectors (commonly referred to as mine detectors) are now capable of signaling the presence of minute piece of metal. However some mines are metal free on certain virtually non-metal. These non-metals challenge the capacity of current metal detectors EXPLOSIVE DETECTION The explosives are one common ingredient that is found in all mines. Detecting explosives however is a complicated process. Modem airports have explosive detecters, which can detect small traces of explosives in suitcases and other containers. Locating traces or the order of explosives is an open field demands technology that can operate in an unlimited variety of environmental 6

7 conditions that are subjected to wind, water and soil changes and variations. Explosive detection under field conditions has recently become the preview of mine detection dogs. A dog s nose has proven to be a very sophisticated and reliable sensor, however handling maid detection dog teams and ensuring consistent behaviour in varied hazard scenarios is a complicated and demanding tasks. In all the above said methods mine detection in conducted in close proximity. That is detection is conducted after going very near to the mine. This method can prove to be dangerous in many occations. So it is not considered to be the safest method. A preferred method is to use detection devices that locate land mines at a safe distance from the deminer. Using 7

8 detection devices that pinpoint land mines exploded from a distance either overhead on at ground level in the best possible way to determine the actual location of individual land mines. Ones the threat is located, that is mines are pin pointed, we can deactivate it safely. This is where the importance of mine detection using radar bullet comes. CHAPTER 5 WHAT IS A RADAR BULLET? The radar bullet is a special type of bullet. The main use of radar bullet is to find landmines without setting foot on the ground. This consists of firing a special bullet in to the ground from a helicopter, which could pin point buried land mines. The bullet units a radar pulse as it grounds to a halt. This pulse strikes the mine and its image gets available on the computer in the helicopter, offering a safe and efficient way of finding land mines. 8

9 CHAPTER 6 RADAR PRINCIPLE Radar is Radio detection and ranging. Radar is a sensor. Radar makes use of radio waves to detect and locate objects. The purpose is to provide estimates of certain characteristics of its surroundings most commonly the presence, position and motion of aircrafts, ships and other vehicles. Radar operates by transmitting electro magnetic energy into the surroundings and detecting energy reflected by object. If a narrow beam of this energy is transmitted by the directive antenna, the direction from which reflections come and hence the bearing of object may be estimated..the 9

10 distance to the reflecting object in estimated by measuring the period between the transmission of radar pulse and reception of echo. In radar bullet principle the change of medium by the waves must be taken into consideration. Transmitter OBJECT RECEIVER DISPLAY Radars have generally from principal parts, the transmitter antenna receiver, and display. The transmitter will transmit an electro magnetic signal through the antenna, which will hit the target and reflects back. The same antenna and 10

11 the time difference between the signal transmission and reception is calculated, which will help up to measure the distance of the target from the radar. CALCULATIONS R OBJECT RADAR T =time b/w signal transmission and reception. 2R c = Total distance traveled. = Velocity of electromagnetic signals = 3*10 8 m/sec. Velocity = distance / time i.e.; C = 2R / T or, R =CT /2 11

12 radar. So in the screen an obstacle will be shown at a distance R from the CHAPTER 7 EXPERIMENTAL SET UP First of all a special bullet in fired downward into the ground, from a gun mounted on a helicopter flying about 100 m above the ground. The bullet in designed in such a way that it gives out powerful blast of radio waves from under the ground. The bullet will produce a pulse of radio waves as it pierces the ground and signal is reflected from any landmines within about a 15 meter radius will be detected by an antenna on the helicopter. 12

13 Once the mines are located they can be destroyed at once or there exact position are noted so they can be destroyed at once on their exact positions are noted so that can be diploid later. And if the bullet hits it, it would explode. The Radar pulse is generated from the bullets kinetic energy by a process known as, Magnetic flux compression. EXPERIMENTAL SETUP 13

14 CHAPTER 8 14

15 MAGNETIC FLUX COMPRESSION Inside the bullet is a metal cylinder, surrounded by a tightly wounded coin of wire. As the bullet leaves the gun, there is a battery generating a magnetic field in the cylinder. When the bullet smashes into the ground,the sudden deceleration forces the cylinder out from inside the coil. The sudden movement of the metal cylinder through the magnetic field induces a large pulse of current in the coil. The coil thus acts like an antenna converting the pulse into a short burst of high frequency radiation. MAGNETIC FLUX COMPRESSION 15

16 CHAPTER 9 FIELD TESTS After the laboratory tests, tests where conducted at the Arizona desert. Using the same experiment set up, the radar bullet as able to detect 35 cm anti tank mines and Val Mara 69 anti personal mines, which are a particular problem in northern Iraq, where the mines have been laid by Saddam Hussein s forces in their confrontation with the Kurds ADVANTAGES The light weight system can be fitted to any helicopter ie; gun, computer controls etc. Extremely small bullets can be used for detection A 30 mm bullet gives out a 4 kw radar pulse. Almost 10 times move power than a standard ground penetrating radar from 20cm down. Also since the bullet is beneath the surface of the ground, it transmits more radio wave into the ground. For ordinary penetrating radar, little radiation penetrates the soil, most is reflected by the ground because of the sudden change in density between the air and the soil. Here the radiation has to change the medium twice. First from air to ground, and then after reflection, from ground into air. Therefore weak signals are 16

17 obtained. But in radar bullet principle the radiation has to change the medium only once i.e.; from the ground into the air and hence stronger signals are obtained DISADVANTAGES It cannot detect plastic land mines, but researches are working hard to overcome this. Since the equipment is to be mounted on a helicopter, the cost of operation is higher. But considering its future prospects and the static s released by red Cross, cost can never be considered as a disadvantage APPLICATIONS It can be used for detecting land mines. It can be used for detecting buried pipelines.for example: - Recently an illegal pipeline carrying drugs between Afghanistan and Turkmistan has been discovered. Such type of illegal pipelines can be detected out by using radar bullet. 17

18 CHAPTER 10 FUTURE PROSPECTS As the UN has already implemented a worldwide ban on antipersonal mines. The invention of radar bullet helps to speed up the destruction of mines. Ten thousands of anti - personal mines lied buried in the hilly regions of Cambodia / north - Korea / Afghanistan etc. And according to UN it would take more than 100 years to detect and destroy these, if worked out manually. Mine clearance or demining is normally broken into three stages. Detection, Removal and Disposal. Current detection methods range from high tech electronic [ground penetrating radar infrared, magnetic resonance imaging] to biological detection schemes (dog snuffers and insect or bacteria ) to simple brute forces detection methods (Rails, Rollers and plows) and use of hand-held mechanical plodders.most of these methods are very slow and/or expensive and suffer from a high false alarm rate. So with helicopter and radar bullet, the mines can be cleared easily. 18

19 Mass graveyards which result from internal civil wars as in Combodia, Kosoro and in same African nations can be detected using radar bullets. This can be applied is future space travels, when we go to a different planet, in that case we can shoot this bullet in to the ground and detect mineral deposits and other deposits. 19

20 CHAPTER 11 CONCLUSION Mines are major cause of concern in many countries. Detection and removal of mines is very important as it is hazardous to both man and animals alike. The conventional methods that are being used right now for mine detection involves working in close proximity for the mines. So overall mine detection using radar bullets is a cutting edge technology that is safe and effective. With all its advantages it may be hoped that mine detection using radar bullets will be more used in detection of mine there by making the world safer place to live in. 20

21 REFERENCES BOOKS S.VITEBSKIY AND L.CARIN Late time resonant frequencies buried bodies of revolution L.CARIN, R KAPOOR, C.E BAVAM. Polarimatic SAR imaging of buried land mines MERILL.1. SKOLNIK. Tata MC Grawhill WEBSITES

22 ABSTRACT Land mines are a case of serious threats to the life of civilians, especially in mine-affected countries like Afghanistan and Iraq.The mines which are implanted during the war time may remain undetected for several decades and may suddenly be activated after that. There are several methods for detection of land mines, such as metal detection and explosive detection. These ways of detection are dangerous because they are done very close to the mine. A safe method for detecting land mines is mine detection using radar bullets. As the name suggests detection is done using Radar Bullets and hence can be done further away from the mine. Detection is usually done from helicopters. Researchers are being conducted to overcome certain inefficiencies of this method. 22

23 CONTENTS CHAPTERS Page No. 1. INTRODUCTION 1 2. MINE AFFECTED COUNTRIES 2 3. WHAT IS A LAND MINE? 3 4. HOW IS METAL DETECTION CURRENTLY BEING CONDUCTED? METAL DETECTION EXPLOSIVE DETECTION 6 5. WHAT IS A RADAR BULLET? 8 6. RADAR PRINCIPLE 9 7. EXPERIMENTAL SETUP MAGNETIC FLUX COMPRESSION FIELD TEST ADVANTAGES DISADVANTAGES APPLICATIONS FUTURE PROSPECTS CONCLUSION REFERENCES 20 23