This document proposes a metal detection robot that can detect metals ahead of it and avoid collisions using ultrasonic sensors. The robot uses an Arduino Uno microcontroller board to control two DC motors via a motor driver chip and detect metals using a metal detector coil. Ultrasonic sensors help the robot detect and avoid obstacles to provide a safe metal detecting robot that can operate in hazardous environments.

1. NATIONAL INSTITUTE OF TECHNOLOGY MANIPUR
(An Autonomous Institution, Under MHRD, INDIA)
Submitted by:
1
Under the guidance of:
METAL DETECTION ROBOT WITH COLLISION AVOIDANCE

2. OVERVIEW
 Objective
 Proposed system
 Module description
 Hardware and software requirements
 Expected output
 Advantages and Disadvantages
 References
2

3. OBJECTIVE
 The main objective of our project is to build a robotic vehicle that
can sense metals ahead of it.
 To search interesting stuff from where people are not able to reach.
 To provide safety to the bomb disposal squad .
 An obstacle sensor is used protect the robot from collision.
 Ability to work in any hostile environment.
3

4. PROPOSED SYSTEM
 This project is divided into modules for better understanding of the
circuit . The modules include
 Arduino UNO Microcontroller Board
 Motor Control Driver
 Metal Detector
 Ultrasonic Sensors
4

5. BLOCK DIAGRAM
5

6. Arduino UNO Microcontroller Board 6

7. Microcontroller
 It is a smaller computer.
 Has on-chip RAM, ROM, I/O ports...
7

8. Arduino UNO Microcontroller
Microcontroller ATmega328
Operating Voltage 5V
Pin Count 28
Input Voltage (recommended) 7-12V
Digital I/O Pins 14 (of which 6 provide PWM output)
Analog Input Pins 6
Current per I/O Pin 40 mA
Current for 3.3V Pin 50 mA
Flash Memory 32 KB (of which 0.5 KB used by boot loader)
SRAM 2 KB
EEPROM 1 KB
Clock Speed 16 MHz
8

9. Motor Control Driver
 Motor Shield is a dual full-bridge driver designed to drive DC
motors.
 It control the speed and direction of each DC motors
independently using the microcontroller .
 It uses L293D IC to control the motor.
 The Motor Shield is powered only by an external power supply of
5V to 12V.
9

10. MOTOR DRIVER L293D
 L293D is a dual H-bridge motor driver integrated circuit
(IC).
 Motor drivers act as current amplifiers since they take a low-
current control signal and provide a higher-current signal.
 This higher current signal is used to drive the motors.
 L293D contains two inbuilt H-bridge driver circuits. In its
common mode of operation, two DC motors can be driven
simultaneously, both in forward and reverse direction.
10

11. Operation of Motor Driver
 L293D has 2 set of arrangements where one set has input
1, input 2, output 1 and output 2 and other set has
input 3, input 4, output 3 and output 4, according to
block diagram if pin no 2 & 7 are high then pin no 3 & 6
are also high.
 If enable 1 and pin number 2 are high leaving pin
number 7 as low then the motor rotates in forward
direction, vice-versa for reverse direction.
 If enable 2 and pin number 10 are high leaving pin
number 15 as low then the motor rotates in forward
direction, vice-versa for reverse direction.
11

12. Metal detector
 The operation of metal detectors is based upon the principles
of electromagnetic induction.
 The single-coil detector is the one used in a real metal
detector.
 A pulsing current is applied to the coil, which then induces a
magnetic field.
 When the magnetic field of the coil moves across metal, such
as the coin, the field induces eddy currents in the coin.
 The eddy currents induce their own magnetic field, which
generates an opposite current in the coil, which induces a
signal indicating the presence of metal.
12

13. Ultrasonic Sensor
 Ultrasonic sensors generate high frequency sound
waves and evaluate the echo which is received
back by the sensor.
 It measures the time interval between sending the
signal and receiving the echo to determine the
distance to an object.
 It detects the distance of the closest object in front of
the sensor (from 2 cm up to 3m).
13

14. Ultrasonic Sensor
 The 5V pin of the Ultrasonic sensor is connected
to the 5V pin on the Arduino.
 The GND pin is connected to the GND pin.
 The SIG (signal) pin is connected to digital pin 7
on the Arduino.
14

15. Expected Outcome
 The Robot will be able to moves in all four directions:
Right, Left, Front, Back .
 The Ultrasonic Sensor will detects the obstacle and avoids collision.
 The Robot will be able to sense metal ahead of it.
15

16. ADVANTAGES
 Provide safety to the bomb disposal squad by providing an extra line of defense.
 Consistency of performance.
 24/7 continuous working.
 Reduced amount of operator errors.
 Can be made to perform even the most dangerous tasks without concern.
16

17. DISADVANTAGES
 Precise programming needed (time, training)
 New products require complete reprogramming.
 Complex and expensive equipment to buy and install.
17

18. Application
 Detecting hidden landmines.
 It can be use for treasure hunt.
 Can be used by the bomb disposal Squad.
18

19. Reference
 http://arduino.cc/en/Main/arduinoBoardUno
 http://arduino.cc/en/Main/ArduinoMotorShieldR3
 http://en.wikipedia.org/wiki/Metal_detector
 http://www.atmel.com/devices/atmega328.aspx
 www.ti.com/lit/ds/symlink/l293d.
19

20. 20