Obstacle observing robot

1. Obstacle Observing Robot
By:
Lokendra Singh
Khinva Singh
Siddhant Rathore
(Electrical Engg. 6th sem)

2. Abstract:-
 In today’s world ROBOTICS is a fast growing and interesting field.
ROBOT has sufficient intelligence to cover the maximum area of
provided space. It has an infrared sensor which are used to sense the
obstacles coming in between the path of ROBOT. It will move in a
particular direction and avoid the obstacle which is coming in its
path. Autonomous Intelligent Robots are robots that can perform
desired tasks in unstructured environments without continuous
human guidance.
The minimum number of gearmotor allows the walking
robot to minimize the power consumption while construct a program
that can produce coordination of multi-degree of freedom for the
movement of the robot. It is found that two gearmotors are sufficient
to produce the basic walking robot and one voltage regulators are
needed to control the load where it is capable of supplying enough
current to drive two gearmotors for each wheel.

3. Why we needs Robotics?
 Mobile robots perform various ways of task to serve human ,in
which some times no human guidance required.
 Robot is a computer controlled machine that is programmed to move
manipulate object, and accomplish work while interacting with
appropriate sensors.
 In this robot IR pairs are used to sens the obstacle and to avoid them,
the IR sensor build with a transmitter and a receiver in each sensor.

4. About the our robot
 Obstacle detection robot are nothing but self thinking
robot which can take decision itself using
programmed brain without any guidance from human
beings
 When the obstacle comes in path of robot IR’s
transmitters transmite the wave which is reflected by
the obstacle to the receiver, then receiver sends that
signal to sensor, thus the obstacle detected.

5. Components used:-
 IR Sensor (with the transmitter and receiver)
 ATmega8 Microcontroller
 Motor Driver
 Motors

6. Circuit diagram of Atmega8 board:-

7. About ATmega8:-
 ATmega8 is a 8-bit microcontroller based on the AVR
RICS architecture.
 By executing powerful instructions in a single clock
cycle, the ATmega8 achieves throughput approaching
1 MIPS per MHz
 In order to maximum performance and parallelism,
the AVR uses a Harvard architecture which separates
memories and buses for program and data.

8. Contd…..
 Instruction in program memory are executed with single
level pipelining
 This concept enables instruction to be executed in every
clock cycle

9. Features of ATmega8:-
 High performance 8 bit Microcontroller
 Up to 16 MIPS throughput at 16 MHz
 32 x 16 general purpose working registers
 Six ADC channels in PDIP package
 Internal Calibrated Oscillator

10. Pin Out diagram:-

11. Pin description:-
 VCC digital supply voltage
 GND ground
 RESET a low level on this pin for longer than the minimum
pulse length will generate a reset , even if the clock is not
running
 AREF the analog refrence pin for the A/D converter
 AVCC the supply voltage pin for A/D converter

12. Port B (PB7….PB0)
 Port B is an 8-bit bi-directional I/O port
 Can be used either as a point port or as output
port(direction must be specified in programming)

13. Port C(PC5….PC0)
 Port C is an 7-bit bi-directional I/O port.
 Can be used either as a input port or as output
port(direction must be specified in programming)

14. Port D(PD7…PD0)
 Port D is an 8-bit bi-directional I/O port
 Can be used either as a input port or as out put
port(direction must be specified in coding)

15. About the IR sensor:-
 IR sensor based on reflected amplitude of the
surrounding objects
 Non-liner and depends on the reflectance
characteristics of the object surface
 IR sensor able to accurately measure distance with
reduced response times

16. Types of IR sensor:-
Active Infrared Sensors
Break Beam Sensors
Reflectance Sensors

17. IR Transmitter and Reciever:-
 Mainly used to generate
IR signals
 Uses timer IC555 in
astable multivibrator
mode to generate square
wave
 Continuous pulses of
50% duty cycle of
frequency 38 KHz

18. Application of IR sensor:-
 Mostly used for distance measurement purposes
 Surface feature detection
 Barcode decoding
 As a tracking system

19. Motor Driver L293D:-
 Quadruple high-current half-H driver.
 Designed to provide bidirectional drive current of up
to 600-mA at voltage from 4.5 to 36V.
 Out put clamp diodes are provided to drive inductive
loads in L293D
 Automatic thermal shutdown.

20. Pin out diagram:-

21. Pin description
 Vcc1 motor supply
 Vcc2 input logic
 A input
 Y output
 1,2 EN enable of first pair 1,2
 3,4 EN enable of second pair 3,4

22. Block diagram of L293D

23. DC Geared Motor:-
 Free running torque &
current are ideally zero
 Increased load implies,
increased torque , current
drawn & power
consumption
 Power supplied by a motor
is the product of output
shaft’s rotational velocity
& torque
 Can run in both direction.

24. Mechanical Design:-
 Design of chassis
 Alignment of circular wheels
 Fixing motors
 Screwing of PCB

26. Advantages & Disadvantages
 Advantages :
 Whenever robot senses any obstacle automatically diverts
its position to left or right and follows the path with out
human guidance.
 The programming of the microcontroller is easy.
 It low cost circuit
 Disadvantages :
 It is use for short distance only.
 It is not recommended to keep the range very long because
this would cause the robot to keep moving forward and
backward as it senses any obstacle.

27. APPLICATIONS
 It can used for the army application.
 It can used in diffence area.
 We can apply number pairs of IR pairs for the safe
direction control of the robot
 It can be used in Mines.

28. Future Aspects:-
 We can extend this project with wireless technology.
 This robot can be used for pick and place the required
object by giving direction to the robot but IR sensor
should be replaced depending upon the application.
 By adding some extra technology it can be
implementation in defense area.

29. Refrences
 http://www.roboticswikipedia.com
 http://www.atmega8wikipedia.com
 N. Senthil Kumar,M.Saravanan,S Jeebananthan ,“Microprocessors &
Microcontrollers”, Oxford University Press,4th Edition,2012,ISBN:978-0-
19-806647-7
 B. Ram, “Fundamental of Microprocessors & Microcontrollers”, Dhanpat
Rai Publication,Seventh Edition, ISBN:978-81-89928-60-5
 http://www.l293dwikipedia.com