PC CONTROLLED ROBOT
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INTRODUCTION
OVERVIEW
In defense service many times it is not affordable in many situations to put human life in trouble in case of rescue operations and emergencies. Requirement of such a situation is to take the inner view of situation without risking any lives. For this purpose a non-living system should be employed. Therefore, we developed an idea to build a robot that does more than just move in a maze.
Having a video signal makes this Robot very useful as a vehicle used for searching and exploring places that human being is limited to such as detecting mines and exploring the unsafe environment. Controlling the robot from different computer a terminal through the internet gives the user flexibility to access it from any computer terminal at any place.
Project Goals
Our goal for the design of project was originally developed from the thought of creating a micro-robot, a robot that finds its way in a maze. This Robot is going to be controlled from a computer with a wide range of functions that we are going to be discussed below. The robot will be controlled from a computer terminal. The user can use the computer to control by using different keys on the computer.
The keys on the computer tell the robot to move forward or reverse, turn right or left, or stop. The on-board RF receiver is sensitive enough for a control range of up to 50 metre. We are also putting a video camera on the robot and sending the video signal on the robot to computer so that the user knows what exactly the Robot is heading.
1. PC:-
Personal Computer is basically used for monitoring the robotic assembly. It is interfaced to RF transmitter with the help of serial port IC(MAX 232) .It is also used for live picture reception from CCTV.Thus PC is used to position the robot in different direction.
2. RF module:-
It is a transreceiver module used for both receiving and transmitting purpose.RF module of 433 MHz is used for this application. It uses AM modulation for transfer of signal. Its coverage area is almost 50m. The cheapest way to remotely control a device for a wide range is via Modulation Technique Now-a-days due to this wide-spread use the required components are quite cheap, thus making it ideal for us to use modulation technique for our project. This topic will explain the theory of operation of RF modulator
The modulator accepts a bit stream as its input and converts it into electrical waveform suitable for transmission over the communication channel. Modulation is a process designed to match the properties of the transmitted signal to the channel through the use of a carrier wave. Modulation is used in communication system for reducing noise and interference, for simultaneously transmitting several signals over a single channel. For this project AM modulation is used.
3. Microcontroller:-
Microcontroller of 8-bit (89C2051) is used in this project. The control signals are received by microcontroller and accordingly will generate control signals to drive the motors. It is programmed so as to get forward, reverse, right, left direction of motor.
The AT89C2051 is a low-voltage, high-performance CMOS 8-bit microcomputer with 2 Kbytes of Flash memory available in 20 pin dual in line package. The device is compatible with the industry standard MCS-51Ô instruction set. By combining a versatile 8-bit CPU with Flash on a monolithic chip, the Atmel AT89C2051 is a powerful microcomputer which provides a highly flexible and cost effective solution to many embedded control applications.
4. Motor Driver unit:-
It uses power transistor TIP 122/127.It is used in Darlington pair form. It is used for control of dc motors. DC motors are connected to robotic assembly through which robot is moved in different direction.
5. CCTV:-
It is a closed circuit TV camera for live video transmission. It is in Mega pixel range. It gives steady picture output to the video transmitter.
6. Video Transmitter:-
Video transmitter is a 4- pin modulator use for general purpose video transmission. It gives both audio and video signal as an output.
7. TV tuner Card:-
It is a video receiver, inbuilt to pc system use for receiving live picture from CCTV.The external robot is used for receiving the picture signal.
8. Power Supply:-
Since the robot is wireless, power supply requirement is fulfilled from DC battery. Battery of 6V is used in this project which can work for long duration, while at transmitter side ac power supply of 230V, 50Hz is used.
Working
The theme of the project is wireless controlled pc robot. Hence the pc (keys of keyboard) is used for controlling the direction of robot. When a key is pressed, signals are converted in RF form trough RF Transmitter using AM modulation via serial port of pc.This signal are further received by RF receiver at receiver section, where it is demodulated , act as a control signal for microcontroller which controls the direction of motor.CCTV on robot is used for picture signal reception and undergoes modulation. This are further demodulated at pc receiver.Such robots are useful in hazardous condition, since it is wireless and controller is away from maze it is highly efficient
CONCLUSION
The aim of our project is to design wireless robot which is controlled by AM modulation. This project includes monitoring the robot through PC. This can be achieved by designing a system which satisfies both the constraints of our project. Automation of robot is achieved by using microcontroller AT89C2051 and Modulation. The remote location can be tracked by using CCTV camera and video transmission. The picture can be observed at T.V receiver.