1.0 INTRODUCTION OF PROJECT Robot becomes widely used in industrial due to their characteristics. Robot able to work in 24 hours continuously without feeling tired unlike human that confine to certain time. The cost to setup the robot nowadays becomes more affordable and their long term prospect is bright judging from their capacity to perform. But in reality, there is no robot where able to function perfectly and still making error. A better controller needed here, to allow the robot performs efficiently and make less error. So, this project is designed to develop a robotic vehicle that follows a specific path. This project uses a microcontroller of 8051 family for its operation. A pair of photo sensors comprising IR transmitter and photo diode is interfaced to the controller to detect the specified path for its movement. Line follower robot is a useful robot that is used in ware houses, industries, and stores, where it follows a dedicated path. This proposed system of a line following robot fulfills the desired functionality and demonstrates the working of it. It uses a pair of photo sensors, comprising of one IR transmitter and a photo diode in each. It guides the robot to follow a specified path by giving appropriate signal to the microcontroller. Two DC motors are used interfaced to the microcontroller through a motor driver IC. Input signals given to the microcontroller from the sensors and
Transcript
1.0 INTRODUCTION OF PROJECT
Robot becomes widely used in industrial due to their characteristics. Robot able to work
in 24 hours continuously without feeling tired unlike human that confine to certain time. The cost
to setup the robot nowadays becomes more affordable and their long term prospect is bright
judging from their capacity to perform. But in reality, there is no robot where able to function
perfectly and still making error. A better controller needed here, to allow the robot performs
efficiently and make less error. So, this project is designed to develop a robotic vehicle that
follows a specific path. This project uses a microcontroller of 8051 family for its operation. A
pair of photo sensors comprising IR transmitter and photo diode is interfaced to the controller to
detect the specified path for its movement.
Line follower robot is a useful robot that is used in ware houses, industries, and stores,
where it follows a dedicated path. This proposed system of a line following robot fulfills the
desired functionality and demonstrates the working of it. It uses a pair of photo sensors,
comprising of one IR transmitter and a photo diode in each.
It guides the robot to follow a specified path by giving appropriate signal to the
microcontroller. Two DC motors are used interfaced to the microcontroller through a motor
driver IC. Input signals given to the microcontroller from the sensors and then the controller
takes the appropriate action according to the program written in it and drives motors as desired.
2.0 OBJECTIVE
The objectives of this project are:
1. Scalability must be a primary concern in the design
2. To make the device automatically tracking the particular path.
3. To design prototype of the robot that can follow the line.
4. To develop a robot that moves through a dark line on light back ground.
3.0 RESEARCH OF THE PROJECT
First of all, some research about the robot available today and how it work is been study.
All this information is important for the next step that will be taken to precede this project. Three
methods are used in doing a research about this project. It is:-
i. Gain information for related book
Books are the first source to refer to do some research. Books can give an accurate output
and the right information when looking at the title. It is not difficult to find a correct title
needed. Some of books are equipped with features, graphs and tables that help collaborates
about the topic. But books also have it weakness. First, it is difficult to understand some of it
sentence or word from book because book is written by someone with a different level of
knowledge and background education. The terminology is always advance and
sophisticated. It is difficult to fully understand what the authors try to explains, plus with
static feature, it is hard to understand everything. Second is difficulty to read with the
numbers and long equations, everything in books seems hard to understand. So to depend on
books alone is not enough. Other sources should be used.
ii. Search from internet
Nowadays, world without boundary is very synonym with millennium era. Internet made
everything in this world seem very small. Information and data can be transfer so fast.
Just a click, any information can be obtained. Anything can be found in internet as long
as it knows how to find it. Just to do is searching. Information about robotics technology
also can be found easily in internet. In internet, there some of websites are come out with
a video or animation to help explaining the related topic. With this features, its help to
understand more compare to books. But internet also has it fuzzy side. Some of
information in internet is untrue information. It is cannot be used as reference. So, it must
be carefully when getting the information to ensure that information is true.
iii. Discuss with expertise
Discussion with expertise about the topic is the best way to gain information about the
robot. It can be done early before refer to other source but it always the best ways if
meeting with expertise after refer to other source. With this step, an expertise would
explain what topic that need more understand and which topics are not related with the
project. Expertise also can help to overcome the problem of understanding books and
compromise any information from internet. In university, expertise is a lecturer, teaching
engineer, tutor and technician that expert related with the project field for examples to
understand of robotic system.
4.0 SCOPE OF PROJECT
The scopes of work are listed as below:-
1. PIC 16F877A microcontroller is selected as a controller of robot.
2. Obstacle detecting sensors to avoid physical obstacles and continue on the line.
3. Robot design and construction.
4. Software development and System demonstration.
5.0 METHODOLOGY
Line Follower Robot is based on hardware and software configuration.
5.1 Materials
Resistor
Quantity References Value
1 R1 220 Ω
1 R2 10 kΩ
3 4.7 kΩ
6 330 Ω
3 10 kΩ (Trimmer)
Capacitor
2 C1 , C2 0.3 µF
2 C3 , C4 30 pF
2 C5 , C6 100 µF (25 V)
Integrated Circuit
1 UI 7805 (Voltage Regulator)
1 U2 PIC16F877A
1 L293D (Motor Driver)
1 LM324 (Comparator)
Diode
1 D1 IN4007 (Diode)
1 LED1 LED- Green
3 LED
Sensor
3 Infrared Transmitter
3 Infrared Receiver
Miscellaneous
1 SW1 SW-SPST
1 Push Button
1 X1 Crystal 20 MHz
1 J5 10 ways Straight Box Header
2 Straight Turn 40 pin
4 Terminal Block 2 pin
1 IC Socket 14 pin
1 IC Socket 16 pin
1 IC Socket 40 pin
1 ZIF Socket 40 pin
4 10mm PCB Stand
1 J1 DC Plug/jack (2.1mm)
1 DC Adapter 12V 1A
1 USB IC SP PIC Programmer
5.2 Hardware Development
Figure 1: Block diagram
Figure 2: Infrared Circuit
Figure 3: Motor Circuit
Figure 4: Power Supply and main PIC
1. PIC microcontrollers (PIC16F877A)
PIC microcontrollers (Programmable Interface Controllers) are electronic
circuits that can be programmed to carry out a vast range of tasks. It can be
programmed to be timers or to control a production line and much more. It
also has calculation function, memory and controlled by program. Each pin on
it has specific function. PIC Microcontrollers are relatively cheap and can be
bought as pre-built circuits or as kits that can be assembled by the user. This
PIC microcontroller also can be programmed and erased up to 10,000 times.
Many programming language are supported by this PIC such as C language,
High-Tech C and Pic Basic.
2. IR receiver and IR transmitter
Transmitter and receiver are commonly used in engineering projects for
remote control of objects. In particularly, in Robotic system uses transmitter
and receiver. An infrared emitter is an LED made from gallium arsenide,
which emits near-infrared energy at about 880nm. The infrared phototransistor
acts as a transistor with the base voltage determined by the amount of light
hitting the transistor.Hence it acts as a variable current source. Greater amount
of IR light cause greater currents to flow through the collector-emitter leads.
3. Op-Amplifier (LM324)
If the rays received by the IR- LED receiver are above a particular
threshold then an amplified signal is generated by the amplifier (LM324).
Note that the sensors cannot directly send a signal to the microcontroller as
the signal voltage generated by them is too low and even when sensors are on
white surface signal generated by them will interpreted low by the
microcontroller.
4. 3H-Bridge (L293D)
The microcontroller sends a signal to the H-bride that acts as a switch. If
the signal received by the H-bridge is high it will rotate the motor or else it
won’t do so. Note that microcontroller only sends a signal to a switch which
gives the voltage required by the motor to rotate. Here we are using L293D
which can be used to control two motors.
5.2.1 Software Development
Figure5: Flowchart Software
1. MPLAB
MPLAB Integrated Development Environment (IDE) is a free, integrated
toolset for the development of embedded applications employing Microchip's
PIC® and dsPIC® microcontrollers. MPLAB IDE runs as a 32-bit application
on MS Windows®, is easy to use and includes a host of free software
components for fast application development and super-charged debugging.
MPLAB IDE also serves as a single, unified graphical user interface for
additional Microchip and third party software and hardware development
tools. Moving between tools is a snap, and upgrading from the free software
simulator to hardware debug and programming tools is done in a flash because
MPLAB IDE has the same user interface for all tool.
2. Proteus Software
Proteus is software for microprocessor simulation, schematic capture, and
printed circuit board (PCB) design. It is developed by Labcenter Electronics.
Proteus 7.0 is a Virtual System Modelling (VSM) that combines circuit
simulation, animated components and microprocessor models to co-simulate
the complete microcontroller based designs. This is the perfect tool for
engineers to test their microcontroller designs before constructing a physical
prototype in real time. This program allows users to interact with the design
using on-screen indicators and/or LED and LCD displays and, if attached to
the PC, switches and buttons.
6.0 EXPECTED RESULTS
1) The robot follows a line as demonstrated.
2) It effectively overcomes problems such as “barren land syndrome” and line breaks.
