Map Following Autonomous Robot Computer Science Essay

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The invention of microcontrollers has provided us a complete solution to various problems in our life. Basic aspects of microcontrollers are that they can be combined with other technologies to create multiple things of high utility. In this project I am also controlling a microcontroller wirelessly by programming it.

The progress in automation industry has revolutionarised the world. Many industries have been automated i.e. humans in the industry have been replaced by the more efficient machines, specially automated machines like robots.

1.1 Overview

My project "Map Following Autonomous Robot" is based on data acquisition through wireless communication. Data acquisition involves getting hold of signals and processing the signals to obtain desired information. The components of Map Following Autonomous Robot includes Vectorial Navigation System, data transfer through transceivers, microprocessor, stepper motors with the wheels of the Robot and most important of all is to show the locomotive ability of a ROBOT ( Automated Mobile Vehicle) from point A to point B.

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There are many types of AMV's (Automated Mobile Vehicle) applicable in different industries. My project aims to focus on just the mobility of the AMV i.e. the primary or core issue of any moving robot. Many countries have excelled in automation industry and now considered to be the world's biggest powers. Especially in Defense systems and space researches, automation has changed the aspect of the future of the world. The mobility of a robot can be implemented in different ways. One way is to lay the sensors, through which a robot can judge its path. But this would be a simple method with a fixed path, and robot has no other path to move on. Second method may be Image Processing, but similar drawbacks are there. The third method is to change the graphical map into tabular data and then through antennas the map is loaded to the microprocessor of the robot, which then controls the locomotion. I have studied and made research on the later method which is interesting as well. And the advantage is to create a new path for robot as required.

1.2 Project Summary

Map Following Autonomous Robot is a perfect example of automated mobile vehicles. The graphical data or map is converted into tabular form. This tabular data is sent through antenna connected through a parallel port. At receiving antenna microcontroller receives the data. All the tabular form of data is interpreted in the EEP ROM and manipulated again and again for further instructions. The microcontroller controls the stepper motors attached with wheels of the robot. This enables it to move in the desired direction and distance. This robot can not only move, but also can change its direction at its axis and can travel the desired amount of distance as well.

The graphical map is loaded on a custom mapping software. And with each click of the mouse, line is drawn between the points. Then the whole map is sent as a tabular data to the microcontroller.

This project shows the most important aspect of general AMV's (Automated Mobile Vehicles) which is the locomotion of robot from point A to point B. The vectorial navigation system is used considering the need to develop a generic algorithm which can move the robot from any point to the other.

1.3 Project Features

The main features of the project are:

Locomotion of Robot

Data acquisition

Wireless data transfer

Microcontroller

Stepper Motors

Advance enhancements

Practical implementation in industry

Map Following Robot is the implementation of the above features considering all the resources available to me. Considering the vast field of automation this project reflects only the locomotive ability of a robot.

1.4 Project Milestone

The milestone table is mainly divided into two major phases, where the first phase is completed by June 2009 while the second phase is expected to be completed by 10th of January 2010. Project milestone table is given below

No.

Tasks

Completion Date

1

Initial research/project selection

February 20,2009

2

System design

March 2009

3

Microcontroller programming/testing

April 24, 2009

4

Microcontroller/computer interfacing

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May 21, 2009

5

Report on phase 1

June9,2009

Table -1.1: Project Milestones Phase I

The second phase of our project involves scheming and manufacturing of industrial application so that automation can be more comprehended. This phase is subdivided into four tasks.

Each task along with date of completion is given below:

No.

Tasks

Completion Date

1

Research regarding application

October 13, 2009

2

Parallel communications

October 28, 2009

3

Measurement of application parameters

November 17, 2009

4

Controlled devices

December 12, 2009

5

Final report

January 8,2010

Table-1.2: Project Milestones Phase II

1.5 Initial Research

Choosing this project as solo was a great challenge for me. I tried with all my best efforts and for the expertise my project supervisor was always there with me. The most important challenge was to manage the time and complete my project accordingly. No doubt, Sir Ali Khaqan helped me out with it.

Study of existing work and books.

Preparation of project proposal.

Designing the hardware required

Designing the control scheme

Study of interfacing to parallel port.

System integration.

System Testing.

Debugging and finalizing

Demo and report writing

Week

7th

1-2

7th

3-4

7th

5-6

7th

7-8

8th

1-2

8th

3-4

8th

5-6

8th

7-8

8th

9-10

8th

11-12

8th

13-14

8th

15-16

Task 1

Task 2

Task 3

Task 4

Task 5

Task 6

Task 7

Task 8

Table-1.3: Research

1.6 Problem Description

Problem description has been categorized in two ways.

1.6.1 Problem Definition

Most of the robots used in the industry are either for data acquisition or performing complex nature of work easily. For this robots might need to move from point 1 to point 2. In Pakistan, automation field is relatively new. Many sectors which use automated robots, specially for the purpose of movement of the robot are either path dependent as they move on sensors, or they are connected to the battery with the cables which itself is a complex architecture and space covering issue.

1.6.2 Problem Solution

My research is totally based on the wireless functioning of a robot i.e. no need of any cable is required for the data acquisition. Another aspect of my research is to develop such generic algorithm based on the Vectorial Navigation System that every time the robot is given with a different path to follow.

Also, this research forms the basis of all the advancements made by the Automation Industry these days. Inspired by the idea that how can a Drone (Unmanned Aerial Vehicles) can fly from one point to another, launch an attack and then can return home safely. My idea is to move the Robot from point A to B, every time with a new path to follow and turn the logic 0 to 1 at point B.

1.7 Industrial Applications

1.7.1 Space Exploration

Robots will be a pioneering part of the space program. Breakthroughs have been made in many key technologies of space robots. Astronauts, however, are very expensive resources in space; robots can fulfill many tasks in space and endure the Moon's harsh environment.

On the Moon, robots will climb slopes and maneuver around obstructions to set up scientific facilities, collect research samples and then transmit images and results back to Earth.

Figure-1.1: Space Robot

1.7.2 Defense Industry

Robots have a great future because militaries are interested in utilizing them beyond their existing role as aerial drones or explosive identification/disposal devices. The growth of technology in this arena also shows promise for future development. The juxtaposition of Artificial Intelligence and robotic technology makes the future more exciting from a military point of view. By incorporating new synchronization and control methods and increasing levels of automation, military robots are expected to reduce the burden and risk for future warriors. Developments in cognitive technologies which essentially deal with man machine interaction are likely to develop the science of robotics further.

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Increasing militarization of robotics technology is expected to be a reality tomorrow. Naturally, the Defence Industry is expected to invest much more in this field in the coming years.

Figure-1.2: Unmanned Drone

1.8 Application in Other Fields

Automobile industry

Aviation

Home security

Construction sites

Hospitals and Offices

Bank security

Chapter 2

2. Mechanical Structure of a Robot

2.1 Overall

Under the given time span, budget and resources it is not possible to construct a robot with all the built in features like obstacle detection, artificial intelligence and human brain interface.

My robot is capable of locomotive ability; hence main importance has been given to the locomotive features. The structure is a rectangular box like shape standing vertically. Movement is possible due to the wheels attached at the sides, and supporting tires at front and back sides. Antenna at the top is the receiver. Inside it is microcontroller and circuit. The wheels are connected to the stepper motors which are also connected to the microcontroller.

2.1.1 Antenna

Antenna provides wireless data from the transmitter. So it is the receiver part of the robot. The data from the antenna goes into the EEP ROM of the microcontroller. This receiver is a wireless module that deals with the receiving part only. Both transmitter and receiver antennas are of same type and frequency.

Figure 2.1: Wireless Antenna

2.1.2 Microcontroller

Microcontrollers have become common in many areas, and such as in home appliances, computer equipments, and instruments. They are also used in automobiles, and also applicable to industrial sector. They have become a central part of industrial remotes, robotics, because they are usually used to control a single process and execute simple instructions. Microcontrollers do not need any processing power. Another advantage of Microcontroller is that all the components can be assembled on a single chip. Some complex devices can use multiple processors.

2.1.3 PIC 16F877

The 16F877A has 8k of code space, 368 bytes of RAM and 256 bytes of EEPROM.

Figure 2.2: Microcontroller 16F877

2.1.4 Features

 High-performance RISC CPU

 All single cycle instructions except for program branches which are 2 cycle

 Operating speed: DC - 20 MHz clock input DC - 200 ns instruction cycle

 Up to 8K x 14 words of Flash Program Memory,

 Up to 256 x 8 bytes of EEPROM data memory

 Pin out compatible to the PIC16C73/74/76/77

 Interrupt capability -up to 14 internal/external

 Eight level deep hardware stack

 Direct, indirect, and relative addressing modes

 Power-on Reset (POR)

 Power-up Timer (PWRT) and Oscillator Start-up Timer (OST)

 Watchdog Timer (WDT) with its own on-chip RC Oscillator for reliable operation .

 Programmable code-protection

 Power saving SLEEP mode

 Selectable oscillator options

 Low-power, high-speed CMOS EPROM/EEPROM technology

 Fully static design

 In-Circuit Serial Programming (ICSP) via two pins

 Only single 5V source needed for programming capability

 In-Circuit Debugging via two pins

 Processor read/write access to program memory

 Wide operating voltage range: 2.5V to 5.5V

 High Sink/Source Current: 25 mA

 Commercial and Industrial temperature ranges

2.1.5 PIN Diagram

Figure 2.3: Microcontroller 16F877

2.2 Stepper Motors

A stepper motor (or step motor) is a brushless, synchronous electric motor that can divide a full rotation into a large number of steps. The motor's position can be controlled precisely without any feedback mechanism (see Open-loop controller), as long as the motor is carefully sized to the application. Stepper motors are similar to switched reluctance motors.

Stepper motors are constant power devices.As motor speed increases, torque decreases.The torque curve may be extended by using current limiting drivers and increasing the driving voltage.Steppers exhibit more vibration than other motor types, as the discrete step tends to snap the rotor from one position to another.

2.2.1 Features

This vibration can become very bad at some speeds and can cause the motor to lose torque. The effect can be mitigated by accelerating quickly through the problem speeds range, physically damping the system, or using a micro-stepping driver. Motors with a greater number of phases also exhibit smoother operation than those with fewer phases.

Parallel communication

Before the advent of USB, the parallel interface was adapted to access a number of peripheral devices other than printers, probably one of the earliest devices to use parallel were dongles used as a hardware key form of software copy protection; Zip drives and scanners were early implementations followed by external modems, sound cards, webcams, gamepads, joysticks and external hard disk drives and CD-ROM drives. Adapters were available to run SCSI devices via parallel.

2.3.1 Data Flow

The data flow is a controlled flow of data from input to output. Data is in graphical form which is converted into tabular form data. This tabular data is sent to the parallel port. Antenna is connected to the usb terminal port and to the parallel port.

Data flows through wireless signals to the receiver and is manipulated by the EEP ROM of the controller. The microcontroller controls the stepper motors attached to the wheels. The output is in terms of the movement of the wheels in the required direction or path given by the tabular data.

2.3.2 Flow Control

Flow control is the ability to stabilize the flow of bytes inside a wire. i.e. In order bit by bit transferring to the serial port and then restart the flow without any loss of the bytes, the flow control is needed for modems and other hardware to make them able to jump in instantaneous flow rates.

Chapter 3

3.1 Introduction

"Map Following Autonomous Robot" is based on data acquisition through wireless communication. The components of Map Following Autonomous Robot includes Vectorial Navigation System, data transfer through transceivers, microprocessor, stepper motors with the wheels of the Robot and most important of all is to show the locomotive ability of a ROBOT ( Automated Mobile Vehicle) from point A to point B.

There are many types of AMV's (Automated Mobile Vehicle) applicable in different industries. My project aims to focus on just the mobility of the AMV i.e. the primary or core issue of any moving robot. Many countries have excelled in automation industry and now considered to be the world's biggest powers. Especially in Defense systems and space researches, automation has changed the aspect of the future of the world. The mobility of a robot can be implemented in different ways. One way is to lay the sensors, through which a robot can judge its path. But this would be a simple method with a fixed path, and robot has no other path to move on. Second method may be Image Processing, but similar drawbacks are there. The third method is to change the graphical map into tabular data, and then through antennas the map is loaded to the microprocessor of the robot, which then controls the locomotion. I have studied and made research on the later method which is interesting as well. And the advantage is to create a new path for robot as required.

3.2 Locomotion

The robot has following locomotive capabilities:

Least Turning Angle = 45 degrees

Max Turning Angle (as a whole) = 270 degrees

Map following autonomous robot is a perfect example of Automated Mobile Vehicle (A.M.V). Mobile robots have the capability to move around in their environment and are not fixed to one physical location. In contrast, industrial robots usually consist of a jointed arm (multi-linked manipulator) and gripper assembly (or end effectors) that is attached to a fixed surface.

This project demonstrates locomotive ability of AMV. The graphical map representation is converted into tabular form or tabular data, which then is wirelessly transmitted to the microcontroller of the robot. This microcontroller sends the data into Electronically Erasable Programmable ROM (EEP ROM) which performs the mobility of the robot through stepper motors connected with the wheels of AMV.

Autonomous robots are robots which can perform desired tasks in unstructured environments without continuous human guidance. Many kinds of robots have some degree of autonomy. Different robots can be autonomous in different ways. A high degree of autonomy is particularly desirable in fields such as space exploration, cleaning floors, mowing lawns, and waste water treatment.

3.3 Movement on Wheels

Map following Robot is a wheeled robot and is capable of moving on its axis. For this matter wheels are attached to motors. Only stepper motors can best suit in this position, enabling the robot to move accordingly at the initial poition and to the desired location. It can also move on its axis due to stepper motor effect. Wheels turning opposite to each other cause its movement on that axis.

3.4 Stepper Motors

A stepper motor (or step motor) is a brushless, synchronous electric motor that can divide a full rotation into a large number of steps. The motor's position can be controlled precisely without any feedback mechanism (see Open-loop controller), as long as the motor is carefully sized to the application. Stepper motors are similar to switched reluctance motors (which are very large stepping motors with a reduced pole count, and generally are closed-loop commutated.)

3.4.1 Characteristics

Stepper motors are constant power devices.

As motor speed increases, torque decreases.

The torque curve may be extended by using current limiting drivers and increasing the driving voltage.

Steppers exhibit more vibration than other motor types, as the discrete step tends to snap the rotor from one position to another.

This vibration can become very bad at some speeds and can cause the motor to lose torque.

The effect can be mitigated by accelerating quickly through the problem speeds range, physically damping the system, or using a micro-stepping driver.

Motors with a greater number of phases also exhibit smoother operation than those with fewer phases.

3.4.2 Types

There are three main types of stepper motors:

Permanent Magnet Stepper

Hybrid Synchronous Stepper

Variable Reluctance Stepper

3.4.3 Two-phase stepper motors

There are two basic winding arrangements for the electromagnetic coils in a two phase stepper motor: bipolar and unipolar.

3.4.3.1 Unipolar motors

A Unipolar stepper motor has two windings per phase, one for each direction of magnetic field. Since in this arrangement a magnetic pole can be reversed without switching the direction of current, the commutation circuit can be made very simple (eg. a single transistor) for each winding. Typically, given a phase, one end of each winding is made common: giving three leads per phase and six leads for a typical two phase motor. Often, these two phase commons are internally joined, so the motor has only five leads.

3.4.3.2 Bipolar motor

Bipolar motors have a single winding per phase. The current in a winding needs to be reversed in order to reverse a magnetic pole, so the driving circuit must be more complicated, typically with an H-bridge arrangement. There are two leads per phase, none are common.

3.5 System Description

3.5.1 Mobile Robots

Mobile robots have the capability to move around in their environment and are not fixed to one physical location. In contrast, industrial robots usually consist of a jointed arm (multi-linked manipulator) and gripper assembly (or end effector) that is attached to a fixed surface.

Classification

Mobile robots may be classified by:

The environment in which they travel:

Land or home robots. They are most commonly wheeled, but also include legged robots with two or more legs.

Aerial robots are usually referred to as unmanned aerial vehicles (UAVs).

Underwater robots are usually called autonomous underwater vehicles (AUVs).

The device they use to move, mainly:

Legged robot. Human-like legs (i.e. an android) or animal-like legs.

Wheeled robot.

3.5.3 Robotic Mapping

The goal is for an autonomous robot to be able to construct a map or floor plan and to localize itself in it. Robotic mapping is that branch of one, which deals with the study and application of ability to construct map or floor plan by the autonomous robot and to localize itself in it. A good algorithm in robotic mapping may combine the information from the past, the present and the future. The mapping can be decomposed in three processes:

map learning

localization

Path-planning.

3.5.4 Map representation

The internal representation of the map can be metric or topological:

The metric framework is the most common for humans and considers a two dimensional space in which it places the objects. The objects are placed with precise coordinates. This representation is very useful, but is sensitive to noise and it is difficult to calculate precisely the distances.

The topological framework only considers places and relations between them. Often, the distances between places are stored. The map is then a graph, in which the nodes corresponds to places and arcs correspond to the paths.

Many techniques use probabilistic representations of the map, in order to handle uncertainty.

3.6 Autonomous robot

Autonomous robots are robots which can perform desired tasks in unstructured environments without continuous human guidance. Many kinds of robots have some degree of autonomy. Different robots can be autonomous in different ways. A high degree of autonomy is particularly desirable in fields such as space exploration, cleaning floors, mowing lawns, and waste water treatment.

Some modern factory robots are "autonomous" within the strict confines of their direct environment. It may not be that every degree of freedom exists in their surrounding environment but the factory robot's workplace is challenging and can often contain chaotic, unpredicted variables. The exact orientation and position of the next object of work and (in the more advanced factories) even the type of object and the required task must be determined. This can vary unpredictably (at least from the robot's point of view).

One important area of robotics research is to enable the robot to cope with its environment whether this be on land, underwater, in the air, underground, or in space.

A fully autonomous robot has the ability to

Gain information about the environment.

Work for an extended period without human intervention.

Move either all or part of itself throughout its operating environment without human assistance.

Avoid situations that are harmful to people, property, or itself unless those are part of its design specifications.

An autonomous robot may also learn or gain new capabilities like adjusting strategies for accomplishing its task(s) or adapting to changing surroundings.

Autonomous robots still require regular maintenance, as do other machines.

3.6.1 Self Maintenance

The first requirement for complete physical autonomy is the ability for a robot to recognize its master and to take care of itself. Many of the battery powered robots on the market today can find and connect to a charging station.

3.6.2 Sensing the Environment

Exteroception is sensing things about the environment. Autonomous robots must have a range of environmental sensors to perform their task and stay out of trouble.

3.6.3 Task Performance

The next step in autonomous behavior is to actually perform a physical task. A new area showing commercial promise is domestic robots, with a flood of small vacuuming robots beginning with iRobot and Electrolux in 2002. While the level of intelligence is not high in these systems, they navigate over wide areas and pilot in tight situations around homes using contact and non-contact sensors. Both of these robots use proprietary algorithms to increase coverage over simple random bounce.

The next level of autonomous task performance requires a robot to perform conditional tasks. For instance, security robots can be programmed to detect intruders and respond in a particular way depending upon where the intruder is.

3.7 Block Diagram

Software

(VB Code)

Parallel Port

Figure 7

Tx

Data Control and Transmission Unit

Microcontroller (16F877) Rx

EEP ROM

DRIVES

MOTOR 2

MOTOR 1

3.8 Mobile robot navigation

A manually tele-op'd robot is totally under control of a driver with a joystick or other control device. A tele-op'd robot is typically used to keep the operator out of harm's way. Examples of manual remote robots include Robotics Design's ANATROLLER ARI-100 and ARI-50, Foster-Miller's Talon, iRobot's PackBot, and KumoTek's MK-705 Roosterbot.

A guarded tele-op robot has the ability to sense and avoid obstacles but will otherwise navigate as driven, like a robot under manual tele-op. Some of the earliest Automated Guided Vehicles (AGVs) were line following mobile robots. They might follow a visual line painted or embedded in the floor or ceiling or an electrical wire in the floor. Most of these robots operated a simple "keep the line in the center sensor" algorithm. They could not circumnavigate obstacles; they just stopped and waited when something blocked their path.

An autonomously guided robot knows at least some information about where it is and how to reach various goals and or waypoints along the way. "Localization" or knowledge of its current location is calculated by one or more means, using sensors such motor encoders, vision, Stereopsis, lasers and global positioning systems. Positioning systems often use triangulation, relative position and/or Monte-Carlo/Markov localization to determine the location and orientation of the platform, from which it can plan a path to its next waypoint or goal. It can gather sensor readings that are time- and location-stamped, so that a hospital, for instance, can know exactly when and where radiation levels exceeded permissible levels. Such robots are often part of the wireless enterprise network, interfaced with other sensing and control systems in the building. For instance, the PatrolBot security robot responds to alarms, operates elevators and notifies the command center an incident arises. Other autonomously guided robots include the SpeciMinder and the Tug delivery robots for hospital labs, though the latter actually has people at the ready to drive the robot remotely when its autonomy fails. The Tug sends a letter to its tech support person, who then takes the helm and steers it over the Internet by looking through a camera low in the base of the robot.

More capable robots combine multiple levels of navigation under a system called sliding autonomy. Most autonomously guided robots, such as the Helpmate hospital robot, also offer a manual mode. The MOBILEROBOTSinside guidance system, which is used in the ADAM, PatrolBot, Speci-Minder, MapperBot and a number of other robots, offers full sliding autonomy, from manual to guard to autonomous mode.

Chapter 4

4.1: Introduction to Devices

This chapter has a brief detail about the devices which is discussed as under:

4.1.1 Microcontroller

Microcontroller is an integrated chip it is often a part of an embedded system. It includes a CPU, RAM, I/O ports, and timers similar to that of a computer. It is different from a microprocessor. Microprocessor is multi purpose IC that is used in creating a multifunction computer and it performs different tasks where as a microcontroller is fully functional on a mono chip. The main advantage of microcontrollers is that they use less power and they are also cheaper.

Microcontrollers have become common in many areas, and such as in home appliances, computer equipments, and instruments. They are also used in automobiles, and also applicable to industrial sector. They have become a central part of industrial remotes, robotics, because they are usually used to control a single process and execute simple instructions. Microcontrollers do not need any processing power. Another advantage of Microcontroller is that all the components can be assembled on a single chip. Some complex devices can use multiple processors.

4.1.2 Function of a Microcontroller

Most Microcontrollers are general purpose Microprocessors that have additional parts that allow them to control external devices and other additional components. Microcontroller has following main purposes:

It takes the input from different sensors.

A designer can use it for processing the inputs.

Microcontroller also has different output options which help us to control different output devices.

Microcontroller is a very strong tool that allows a coder make a special purpose design. The person can create unlimited versions on the design by manipulating the code.

4.1.3 Features

 High-performance RISC CPU

 All single cycle instructions except for program branches which are 2 cycle

 Operating speed: DC - 20 MHz clock input DC - 200 ns instruction cycle

 Up to 8K x 14 words of Flash Program Memory,

 Up to 256 x 8 bytes of EEPROM data memory

 Pin out compatible to the PIC16C73/74/76/77

 Interrupt capability -up to 14 internal/external

 Eight level deep hardware stack

 Direct, indirect, and relative addressing modes

 Power-on Reset (POR)

 Power-up Timer (PWRT) and Oscillator Start-up Timer (OST)

 Watchdog Timer (WDT) with its own on-chip RC Oscillator for reliable operation

 Programmable code-protection

 Power saving SLEEP mode

 Selectable oscillator options

 Low-power, high-speed CMOS EPROM/EEPROM technology

 Fully static design

 In-Circuit Serial Programming (ICSP) via two pins

 Only single 5V source needed for programming capability

 In-Circuit Debugging via two pins

 Processor read/write access to program memory

 Wide operating voltage range: 2.5V to 5.5V

 High Sink/Source Current: 25 mA

 Commercial and Industrial temperature ranges

4.2 Analog to Digital converter (ADC)

The function of analog to digital converter is to produces a digital word which represents the magnitude of some analog voltage or current. The resolution of an analog to digital converter refers to the number of bits.

The accuracy specification of an analog to digital converter is a comparison between the actual output and input. A converter is said to be high speed if it has a short conversion time. It can perform Parallel or Flash Conversion, Successive Approximation and Integrating or Dual Slope Conversion.

We are using ADC0848 in our project.

4.3 Analog to Digital Converter 0848

The ADC0848 are CMOS 8-bit successive approximation Analog to Digital converters with versatile analog input multiplexers. The 4-channel or 8-channel multiplexers can be software configured for single-ended, differential operation.

The differential mode provides low frequency input which allows offsetting the analog range of the converter.

They are designed to operate from the control bus of a wide variety of microprocessors. TRI-STATE output latches that directly drive the data bus permit the A/Ds to be configured as memory locations.

Features

It has Easy interface to all microprocessors

It has voltage reference

Internal clock is available

Its input range is 0Vto 5V.

No adjustment is required for zero or full scale

It has 28 pin modeled chip

4.4 Parallel Port

A parallel port is a type of interface found on computers (personal and otherwise) for connecting various peripherals. It is also known as a printer port or Centronic port. The IEEE 1284 standard defines the bi-directional version of the port.

Before the advent of USB, the parallel interface was adapted to access a number of peripheral devices other than printers. Probably one of the earliest devices to use parallel were dongles used as a hardware key form of software copy protection. Zip drives and scanners were early implementations followed by external modems, sound cards, webcams, gamepads, joysticks and external hard disk drives and CD-ROM drives. Adapters were available to run SCSI devices via parallel. Other devices such as EPROM programmers and hardware controllers could be connected parallel.

In early parallel ports the data lines were unidirectional (data out only) so it was not easily possible to feed data in to the computer. However, a workaround was possible by using 4 of the 5 status lines. A circuit could be constructed to split each 8-bit byte into two 4-bit nibbles which were fed in sequentially through the status lines. Each pair of nibbles was then re-combined into an 8-bit byte. This same method (with the splitting and recombining done in software) was also used to transfer data between PCs using a laplink cable.

4.4.1 Current Use

At the consumer level, the USB interface-and in some cases Ethernet-has effectively replaced the parallel printer port. Many manufacturers of personal computers and laptops consider parallel to be a legacy port and no longer include the parallel interface. USB to parallel adapters are available to use parallel-only printers with USB-only systems. However, due to the simplicity of its implementation, it is often used for interfacing with custom-made peripherals.

4.4.2 Pin Outs

Pin outs for parallel port connectors are:

Pin No (DB25)

Pin No (36 pin)

Signal name

Direction

Register - bit

Inverted

1

1

*Strobe

In/Out

Control-0

Yes

2

2

Data0

Out

Data-0

No

3

3

Data1

Out

Data-1

No

4

4

Data2

Out

Data-2

No

5

5

Data3

Out

Data-3

No

6

6

Data4

Out

Data-4

No

7

7

Data5

Out

Data-5

No

8

8

Data6

Out

Data-6

No

9

9

Data7

Out

Data-7

No

10

10

*Ack

In

Status-6

No

11

11

Busy

In

Status-7

Yes

12

12

Paper-Out

In

Status-5

No

13

13

Select

In

Status-4

No

14

14

Linefeed

In/Out

Control-1

Yes

15

32

*Error

In

Status-3

No

16

31

*Reset

In/Out

Control-2

No

17

36

*Select-Printer

In/Out

Control-3

Yes

18-25

19-30,33,17

Ground

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4.4.3 Unidirectional parallel ports

In early parallel ports the data lines were unidirectional (data out only) so it was not easily possible to feed data in to the computer. However, a workaround was possible by using 4 of the 5 status lines. A circuit could be constructed to split each 8-bit byte into two 4-bit nibbles which were fed in sequentially through the status lines. Each pair of nibbles was then re-combined into an 8-bit byte. This same method (with the splitting and recombining done in software) was also used to transfer data between PCs using a lap link cable.

4.5 Voltage regulator

A voltage regulator is an electrical regulator. It is designed to automatically maintain a constant voltage level. It may use an electromechanical mechanism. It may be used to regulate one or more AC or DC voltages depend on the design. We have used 7809 regulator in our project which is much more efficient than other voltage regulators.

4.6 Transistor (2N2222)

The 2N2222 often referred to as the 'quad two' transistor, is a small, common NPN BJT transistor used for general purpose low-power amplifying or switching applications. It is designed for low to medium current, low power, medium voltage, and can operate at moderately high speeds. It was originally made in the TO-18 metal can as shown in the picture, but is more commonly available now in the cheaper TO-92 packaging, where it is known as the PN2222 or P2N2222.

4.7 USB (Universal serial bus)

USB (Universal Serial Bus) is a specification to establish communication between devices and a host controller (usually personal computers). USB is intended to replace many varieties of serial and parallel ports. USB can connect computer peripherals such as mice, keyboards, digital cameras, printers, personal media players, flas drives, and external hard drives. For many of those devices, USB has become the standard connection method. USB was designed for personal computers, but it has become commonplace on other devices such as smartphones, PDAs and video game consoles, and as a power cord between a device and an AC adapter plugged into a wall plug for charging. As of 2008[update], there are about 2 billion USB devices sold per year, and approximately 6 billion totals sold to date.

Chapter 5

5.1 Project Description

Map following autonomous robot is a perfect example of Automated Mobile Vehicle (A.M.V). Mobile robots have the capability to move around in their environment and are not fixed to one physical location.

This project demonstrates locomotive ability of AMV. The graphical map representation is converted into tabular form or tabular data, which then is wirelessly transmitted to the microcontroller of the robot. This microcontroller sends the data into Electronically Erasable Programmable ROM (EEP ROM) which performs the mobility of the robot through stepper motors connected with the wheels of AMV.

5.1.1 Goal

This project aims to develop a generic algorithm that is based on the Vectorial Navigation System. This sort of navigation helps in moving a robot from one point to another without any human guidance. The primary goal is to show the locomotive ability of an AMV or the Map Following Robot on the desired path or map.

5.2 Problems Faced

I have faced several problems during different phases of the project. Some of the problems are given below:

5.2.1 Selection of components

Initally I did not know which type of components should be used in the project. I had some difficulties in the selection of a Microcontroller because various types of controllers are available in market including 89C51, 8086, 89C52, PIC and AT mega16. After a long discussion with my supervisor we tried to search for the Microcontroller which best suites the project. Finally we decided to use 816F877 as the main control and transmission unit in the project.

5.2.2 Selection of batteries

The battery power had to be included in the mechanical structure. Initaially I used batteries which were too heavy for the robot. Then I chose single battery source of 6 Ampere current and 12 V voltage.

5.2.3 Selection of Wheels and Stepper Motors

The most important part of the robot is the wheels and the stepper motors connected to them. Power of the stepper motor should be such that it can move the wheels. But initially many stepper motors were changed and sumtimes the wheels. But at the end got the desired combination for them.

5.3 Future Enhancements

This project reflects the vast field of automation industry and the enhancements taking place in it. It is a very vast field of knowledge considering that mankind kind is goin to depend on the robots in the near future. Many countries are taking deep interest in this field as it is linked to the defence systems of the country now. Budget is announced to initiate research work on a large scale. This is the reason that in every school of life, autonomous robots will be replacing mankind and sharing a lots of work. If following enhancements can be achieved by the researchers, highly qualified and intelligebt robots can be made.

5.3.1 Human Machine Interface

Human Machine Interface is the algorithm that can be used in a robot or any AMV so that aotumated robots and humans can interact. This would help robots to recognize voice of people, images and speech. Thus robot will be available in the offices as working class. Thi is an idea that with this revolution robots will quickly replace human efforts.

5.3.2 Artificial Intelligence

This enhancement has already been a main achievement in the field study of robots. Considering the mobility of robot, this algorithm will help in managing obstacle detection and other necessary items like self charge or go to sleep mode.

5.3.3 Home Automation

This project can be expanded in future for automation of home appliances. We can control and monitor different home appliances. We can also monitor these appliances. This project can be used to efficiently control and monitor home appliances using robotic management.

5.4 Future of Robotics

Robots are already a part of our lives. Industrial robots widely used in manufacturing. Military and police organizations use robots to assist in dangerous situations. Robots already have a significant role in medicine. Robots are helping doctors achieve more precision in the operating room, performing safer, less invasive techniques.

5.4.1 Civil Use

Caterpillar plans to develop remote controlled machines and expects to develop fully autonomous heavy robots by 2021. Some cranes already are remote controlled It was demonstrated that a robot can perform a herding task. Robots are increasingly used in manufacturing since 1960s. In auto industry they can amount for more than half of the labor. There are even lights off factories such as an IBM keyboard manufacturing factory in Texas that are 100% automated. Robots such as HOSPI are used as couriers in hospitals, etc. Other hospital tasks performed by robots are receptionists, guides and porters helpers, Robots can serve as waiters and cooks.

5.4.2 Surgical Robots

Surgical Robots towards autonomy:

Current surgical robots are tactical: every move authorized by a surgeon.

Telesurgery already requires local autonomy.

Miniaturization and new MIS techniques lead to strategic robots.

Robotics will become ubiquitous in future.

5.5 Other Future Applications

Military robots for the future

Robots for household purposes

Robots with sense of touch

Brain machine interface etc.

Conclusion

The idea of this project is to show the locomotive characteristics of Automated Mobile Vehicle i.e. Map Following Autonomous Robot. The unique feature of this report is that Autonomous Robot follows the path independently (without Human guidance) and the data is transmitted wirelessly through the transceivers. Unlike other autonomous robots used in the industry, this implementation of AMV (Automated Mobile Vehicle) does not require any specific path every time for the motion from point A to point B. Instead every time the user can define a new path for the robot to follow. This can be done through the custom mapping software made in the Visual Basic. Hence, graphical data is converted into tabular form and is then transmitted over wireless signals.

The most inspirational application of this project for me is the Drone (Aerial Vehicle). It is an obvious example for us, specially being Pakistanis. It follows the same logic of an AMV (Automated Mobile Vehicle) with additional software cores of obstacle detection, artificial intelligence and the ability to go aerial instead of moving on wheels.

This project was to implement an autonomous robot and if at point B, or at the destination we can turn the logic from 0 to 1, it means the day is not far that we can make our own applications of the same logic. So it can be concluded that in near future robots will be sharing in every aspect of human life and defense of the country would highly be dependent on the AMV's (Automated Mobile Vehicles).