الفهرس 
Chapter 1 INTRODUCTIONOnly 14 pages are availabe for public view
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Abstract
Detection and removal of antipersonnel landmines are serious problems that threaten many countries in the world. Therefore, it has become one of the major scientific and technological challenges. Their solution requires the cooperation of various engineering disciplines for solving these challenges. In recent years, many organizations and universities in different countries have increasingly recognized the significance of low cost and sustainable technologies for mine detection and extraction. Conventional methods of demining are expensive, slow, inflexible and less efficient. There is a dire need for automated, efficient, low-cost, and self powered robotic systems for the purpose of mine detection and disposal. This thesis deals with the design, development and implementation of a novel low cost robotic system for mine detection and extraction. This robotic system consists of a mobile platform carrying flexible arm, the sensors system and the developed electronic cards of the system. The sensors system comprises an efficient mine detector sensor in addition to a distributed sensors fusion system that identifies the robot environment and operation. The mine detector sensor is combined to the robot head and the robot head is supplemented to the robot arm in such a way that flexible movement of this detector over ground surface is achieved in order to increase the robot’s scanning capability. When the robot detects a buried landmine, the discrimination process for this landmine starts by identifying the size and the position of this mine. After the identification process, the digging process takes place by drilling the soil around the mine without touching it. The drilling
mechanism is achieved using four metal fingers fixed to a rotary wheel coupled with a motor of 500 watt of electric power. The metallic fingers operate in such a way that the speed and the torque of the rotary wheels are controlled during the digging operation. The drilling, catching and extracting mechanisms are carried out properly without hurting the mine. As soon as the metallic fingers reaching and sensing the mine, the fingers begin to close for catching the mine, the whole head, then goes up to specific distance above the ground and the main arm moves to right away from the robot’s path.
The robot’s sequences of operations are controlled wirelessly from the operator’s hand held unit. This objective is achieved using four circuits, three of them are combined together with serial connection (mine detection circuit – sensors circuit – relays and motors circuit) and the fourth circuit is connected through wireless connection (hand held circuit). The four circuits have four PICs MCs that have the capability to monitor, process, drive eight DC motors and handle the signals of 11 sensors, motor encoders, two LCDs, 2 flashers, sound alarm, transmitting-receiving wireless module and the signal from the metal detector sensor. The output signals from the mine detection circuit and sensors circuit, control and determine the robot’s modes of operation according to the applied programs in the PICs MCs.
The power supply supplementing the robot is obtained using regenerative technology. This is achieved by developing two axes automatic solar tracking system installed on the robot. The tracking system is controlled using a microcontroller programmed with astronomical algorithm to keep the solar panel at right angle with respect to the incident sunrays. Moreover, a liquid capacitive
inclinometer chip is used for measuring the tilt angle of the solar panel with respect to ground and robot’s inclined angle within 0 to 90 degree range and an electronic compass is issued for adjusting the azimuth solar angle direction for any movement of the robot on the ground. These devices ensure that the sun rays are always perpendicular to the solar panel, irrespective of the robot’s direction or inclination on the ground. A PWM controlled DC-DC charge controller Boost converter is used along with the automatic tracking system for charging and protecting the dc battery from over charged / over discharged conditions. Control of the overall system has implemented using PIC 18F452 microcontroller circuit.