Automatic robotic vehicle avoiding obstacle and detecting metal provided with an manual control through bluetooth

1. AUTOMATED METAL DETECTOR ROBOTIC
VEHICLE WITH MANUAL CONTROL USING
BLUETOOTH
SUBMITTED TO : SUBMITTED BY:
MR.DEVENDRA GOYAL ABHINAV MAGGU
(ASSTN. PROFFESOR RENUKA VERMA
OF EELECTRICAL DEPARTMENT) VAIBHAV GUPTA
EE 6TH SEMESTER

2. TABLE OF CONTENTS:
• INTRODUCTION
• ABOUT MICROCONTROLLER (ATMEGA8)
• ABOUT MOTOR DRIVER I.C.
• ABOUT PIR SENSORS
• ABOUT METAL DETECTOR
• WORKING OF METAL DETECTOR
• BLUETOOTH MODULE(HC-05)
• FURTURE ADAPTAITON
• CONCLUSION
• REFRENCES

3. What does our robot do !
The project is designed to develop a robotic vehicle that can
sense metals ahead of it on its path similar to sensing land
mines. The robot is controlled by an android mobile with an
App using Bluetooth technology. It has been provided with
I.R sensor controlling the two dc motor of vehicle to avoid
any obstacle in its path. It consists of a metal detector circuit
consisting of an inductor coil sensing current changes which
is interfaced to the control unit that alarms the user behind it
about a suspected land mine ahead. The robot will move
automatically while avoiding any rocks and other obstacle
and search for metal in unknown locations as it detects any
sign of metal it will immediately stop and a buzzer will start
ringing.

4. INTRODUCTION……
• An obstacle avoiding refers to the ability of a robot to detect the obstacel in its way
if there are any and thus make its own obstacel free path
• Metal detectors are devices that use electromagnetic fields to detect and signal the
presence of metallic or ferromagnetic objects.
• In this robot we have used bluetooth connectivity (HC-05 module) to operate the
metal detecting robot through an ANDROID APP.
• In this robot we use a microcontroller, motor driver I.C. ,PIR sensors ,metal
detector circuit, bluetooth module(HC-05).

5. COMPONENTS OF ROBOT
• AUTOMATION THROUGH PIR SENSOR AND
MOTOR DRIVER IC’S CONNECTED TO THE
BOARD
• A BLUETOOTH DEVICE CONNECTED IN
PARALLEL TO THE BOARD
• A METAL DETECTOR CIRCUIT

6. Microcontroller (ATmega8)…..
• It is a micro computer chip which stores our programs executes them and takes
necessary action. The chip used here is Atmel popular AVR micro controller.
• It is a 8-bit single chip microcontroller.

7. Motor driver I.C.
L293D……
• Whenever a robotics hobbyist talk about making a robot, the first thing comes to
his mind is making the robot move on the ground. And there are always two
options in front of the designer whether to use a DC Motor or a stepper motor.
• DC motors are always preferred over stepper motors.
• In this part we will learn to interface a DC motor with a microcontroller. Usually
H-bridge is preferred way of interfacing a DC motor.
• L293D is most used H-Bridge driver IC. H-bridge can also be made with the help
of transistors and MOSFETs etc.
• Rather of being cheap, they only increase the size of the design board, which is
sometimes not required so using a small 16 pin IC is preferred for this purpose
• L293 series of chips are power H-bridge motor drivers. The L293D chip is in 16-
pins dip packages, and has two h-bridge drivers. An H bridge is typically capable
of running one DC motor bidirectional (forward, backwards, off), or two separate
motors unidirectional (forward, off).

8. DC-Motors

9. PIN DIAGRAM OF L293D

10. PIR SENSORS
• A passive infrared sensor (PIR sensor) is an electronic sensor that measures infrared
(IR) light radiating from objects in its field of view. They are most often used in
PIR-based motion detectors.
• The term passive in this instance refers to the fact that PIR devices do not generate
or radiate any energy for detection purposes.
• This PIR sensors works as a obstacel avoider .
• This sensors sense the raditions or obeject infront of this it sense and change the
path of robot.

11. Metal detector…….
• The operation of metal detectors is based upon the principles of
electromagnetic induction.
• When the magnetic field of the coil moves across metal, such as the
coin, the field induces eddy currents in the coin.
• The single-coil detector is the one used in a real metal detector.
• 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.
• We can also use an inductive proximity sensor, which can detect only metal.

12. WORKING…..
 A metal detector is an electronic device.
 An oscillator which produces AC current that passes through a coil producing an alternating
magnetic field.
 A part of the metal is near to the coil, eddy current will be induced in the metal
 This produces a magnetic field of its own.
 If another coil is used to measure the magnetic field.
 The change in the magnetic field due to the metallic object can be detected.
 The metal detectors are used to detect the weapons like guns, knives in the airports.
 It is used in the construction industry to detect steel reinforcing bars in wires, concrete, pipes
buried in floors and walls.

13.  The main components a simple metal detector circuit are LC circuit, proximity sensor and the
buzzer.
 The LC circuit is nothing but inductor and capacitor, which are connected in parallel.
 The LC circuit activates the proximity sensor when it senses any metal close to it.
 This sensor glow the LED and makes a buzzer.
 When the LC circuit has any resonating frequency from any metal which is close to it
 The electric field will be created, that will lead to induce current in the coil.
 The change the signal in the flow of the signal through the coil.
 A Variable resistor is used to change the value of the sensor, which is equal to the LC circuit.
 When the metal is detected, the circuit will have changed signal.
 This changed signal will be given to the proximity detector.
 It will detect the change in the signal and react accordingly.
 When the metal is detected by the coil, the o/p of the sensor will be of 1mA

14. SIMPLE CIRCUIT DIAGRAM Of METAL
DETECTOR:

15. Metal detector with buzzer

16. BLUETOOTH MODULE
• HC-05 module is an easy to use Bluetooth SPP (Serial Port
Protocol) module, designed for transparent wireless serial
connection setup
• Hardware Features: Typical -80dBm sensitivity , Up to +4dBm
RF transmit power , Low Power 1.8V Operation ,1.8 to 3.6V
I/O , With edge connector
• Software Features: Default Baud rate: 38400, Data bits:8,
Stop bit:1,Parity:No parity, Auto-connect to the last device on
power as default.
• Permit pairing device to connect as default.
• Auto-pairing PINCODE:”0000” as default
• Auto-reconnect in 30 min when disconnected as a result of
beyond the range of connection

17. Serial Port Bluetooth Module (Master/Slave) :
HC-05

18. Bluetooth with PIR sensor attached
to ATmega8

19. Future Aspects
• The automation done using PIR sensor and
manual control through Bluetooth can also be
used in a household cleaning & mopping robot
• The use of GPS will give you the exact
location if used , similarly the use of ultrasonic
sensor instead of PIR will give more accurate
result
• The range of metal detection could also be
increased by increasing the no. of turns of coil

20. Conclusion
Thus we are able to detect metal with the
following robot while avoiding obstacle
and manual controlling through the
phone.