Automation System For Distribution Of Information

Published Date: 02 Nov 2017

Abstract-The paper describes "Automation System for Distribution of Information" which is a wireless microcontroller based system designed as an aid for conveying vital and confidential multi user information in real time.The data is shared by multiple users at the same time,without delay,in a confined area. The areas where this systems can be used are workshops, companies, database centres etc.

To implement such an idea a scenario of conduction of university examinations in an educational institute is considered .

The system consists of Central Host PC installed with software called Labview 8.6 . Its Graphic User Interface (GUI) will indicate to the chief examiner sitting in the central Exam-cell the information of the classrooms e.g. block number, subject name, supervisor name, exam timing, paper code, etc. All these data will be entered to Labview through its GUI.The Slave module in class room consists of display system which displays 24hrs timing, paper code on alphanumeric displays (ASD) in respective classrooms.

Keywords- zigbee; protocol;central host;slave module

INTRODUCTION

The theory examination held by the Mumbai University is of stipulated hours. According to the rules during the exam it is required for the students and the supervisor to track the various time intervals and follow some important instructions and make announcements. The current examination monitoring procedure is manual. All the instructions and announcements, including the paper code are communicated by the Chief Conductor to the students through the supervisors in the class room. In an Examination centre, consisting of ten to fifteen class rooms, there are delays in the announcements made in different halls and there can be errors. The system can be improved by making it automatic using "Automation System for Distribution of Information".

PROBLEM STATEMENT

Every time, a person has to be allotted to announce paper code and other exam related information. This method is very tedious as it fritters away a lot of time. Also, there can be delay if there are more number of classrooms. Now a days all the vital announcements are being done manually by the supervisor such as:-

wear identity card

1 hour over

1 hour left

10 minutes left

tie-up supplements…etc

So, to overcome these drawbacks, a centralized automated system can be used.

PROPOSED SYSTEM

In this system we have used software called "Labview" setup in a PC located in the exam-cell, on which we will have Graphic User Interface (GUI) to allow the examiner sitting in the exam cell display and announce following in classrooms.

Block number

Subject name

Paper Code

Exam timing

Special messages

All these data will be entered through data base and with the help of serial communication (with an option of RS-422 differential protocol); the paper code will be sent to slave microcontrollers from exam cell PC. Paper code will be displayed with the help of an alphanumeric display in every classroom. Speakers have installed in the classrooms for announcement purpose which are private in topology. Also, classrooms modules are continuously updated with the latest time using a RTC module.

Timing

Description

(15mins before start)

:

Start the RTC system Long-bell ()-gathering in class.

(after 10 mins )

:

Wear your identity card.

Switch off your mobile phones.

Keep hall tickets on your benches.

(exam starts)

:

Short bell (distribution of question paper)

(after 1 hours)

:

Short bell (indicating 1 hour is elapsed)

( after 2 hours)

:

Short bell

( last 10 mins )

:

Short bell ( warning bell )

Last 10 mins left

Please tie-up your supplements

Check supervisor sign on the sheet

Strike out the blank pages and write "END "at the end.

( End of paper )

:

Long bell

Please stop writing.

LITERATURE OVERVIEW

A public address system (PA system) is an electronic sound amplification and distribution system with a microphone, amplifier and loudspeakers, used to allow a person to address a large public, for example for announcements of movements at large and noisy air and rail terminals.

The term is also used for systems which may additionally have a mixing console, and amplifiers and loudspeakers suitable for music as well as speech, used to reinforce a sound source, e.g., recorded music or a person giving a speech, and distributing the sound throughout a venue or building.

Simple PA systems are often used in small venues such as school auditoriums, churches, and small bars. PA systems with many speakers are widely used to make announcements in public, institutional and commercial buildings and locations. Intercom systems, installed in many buildings, have microphones in many rooms allowing the occupants to respond to announcements.

Wireless Public Addresss Paging System : A PA paging system provides schools with a wireless way to incorporate a powerful messaging system for daily and emergency announcements throughout the facility. Schools, campuses, hospitals, office buildings and industrial facilities that need to replace or expand their existing Public Address system can easily accomplish this task by adding indoor or outdoor wireless speakers and horns.

BLOCK DIAGRAM

Figure 1:Basic Block Diagram

WORKING OF MODEL

The Block diagram figure represents the whole system. It has following three main parts:

1.Central Host: This is basically a Desktop PC with Labview Installed. These are responsible for accepting responses from the Exam Supervisor verify input and convert them into corresponding command words and then transmit via RS232.

2. Slave Modules: The slave module is single unit installed in each classroom which is capable of receiving commands from Central Host, interpret them and perform the desired operations.

The various sub-units present in a single Slave Module is shown in Figure 1

Microcontroller P89V51RD2

RS 422 to TTL converter

RTC unit

Display and Display Driver

Audio Circuitry

In this project user is supposed to use only a Labview based GUI which will take care of getting information from the user and converting them into appropriate command words and transmitting them serially.

The command word transmitted is received by all slave modules at the same time, but it will be accepted by only that module whose module address is specified in the command word. The slave module will then process the ASCII command to know what is meant to do and then perform the required operation.

A. MICROCONTROLEER: P89V51RD2

The P89V51RD2 is an 80C51 microcontroller with 64 kB Flash and 1024 bytes of data RAM.

A key feature of the P89V51RD2 is its X2 mode option. The design engineer can choose to run the application with the conventional 80C51 clock rate (12 clocks per

machine cycle) or select the X2 mode (6 clocks per machine cycle) to achieve twice the throughput at the same clock frequency.The Flash program memory supports both parallel programming and serial.

B. XBEE-PRO

The reason behind selecting Xbee- PRO module for wireless transmission is its features which meet the requirement. XBee-PRO Modules were engineered to meet ZigBee/IEEE 802.15.4 standards and address the unique needs of low-cost, low-power wireless sensor networks. The modules require minimal power and provide reliable delivery of critical data between devices. The modules operate within the ISM 2.4 GHz frequency band and are pin-for-pin compatible with each other.

C. RTC UNIT

The DS1307 serial real-time clock (RTC) is a low power, full binary-coded decimal (BCD) clock/calendar plus 56 bytes of NV SRAM. Address and data are transferred serially through an I2C, bidirectional bus.The clock operates in either the 24-hour or 12- hour format with AM/PM indicator. The DS1307 has a built-in power-sense circuit that detects power failures and automatically switches to the backup supply.

INTRODUCTION TO LAB VIEW

LabVIEW is a program development environment, much like modern C or BASIC development environments, and National Instruments LabWindows/CVI. However, LabVIEW is different from those applications in one important respect. Other programming systems use text-based languages to create lines of code, while LabVIEW uses a Graphical programming language G, to create programs in block diagram form.

LabVIEW, like C or BASIC, is a general-purpose programming system with extensive libraries of functions for any programming task. LabVIEW includes libraries for data acquisition, GPIB and serial instrument control, data analysis, data presentation, and data storage. LabVIEW also includes conventional program development tools, so you can set breakpoints, animate the execution to see how data passes through the program, and single-step through the program to make debugging and program development easier.

Figure 2:Features Of LabVIEW

LabVIEW is a general-purpose programming system, but it also includes libraries of functions and development tools designed specifically for data acquisition and instrument control.

LabVIEW programs are called Virtual Instruments (VIs) because their appearance and operation can imitate actual instruments. However, VI’s are similar to the functions of conventional language programs. A VI consists of an interactive user interface, a dataflow diagram that serves as the source code and icon connections that allow the VI to be called from higher level VI’s. More specifically, VI’s are structured as follows:

The interactive user interface of a VI is called the front panel, because it simulates the panel of a physical instrument. The front panel can contain knobs, push buttons, graphs, and other controls and indicators. You enter data using a mouse and keyboard, and then view the results on the computer screen.

The VI receives instructions from a block diagram, which you construct in G. The block diagram is a pictorial solution to a programming problem. The block diagram is also the source code for the VI.

VI’s are hierarchical and modular. You can use them as top-level programs, or as subprograms within other programs. A VI within another VI is called a sub VI. The icon and connector of a VI work like a graphical parameter list so that other VIs can pass data to a sub VI. With these features, LabVIEW promotes and adheres to the concept of modular programming. You divide an application into a series of tasks, which you can divide again until a complicated application becomes a series of simple subtasks. You build a VI to accomplish each subtask and then combine those VI’s on another block diagram to accomplish the larger task. Finally, your top-level VI contains a collection of sub VI’s that represent application functions. Because you can execute each sub VI by itself, apart from the rest of the application, debugging is much easier. Furthermore, many low-level sub VI’s often perform tasks common to several applications, so that you can develop a specialized set of sub VI’s well-suited to applications you are likely to construct.

FUTURE SCOPE

Hand held module for direct communication between teacher/supervisor with the exam cell or other data distribution system using the existing wireless system.

Hand held module for teacher which will have notes reading facility.

Hand held module having laser pointer.

Live video feed from classroom to exam cell.

Replacement of current display with LED dot matrix display which provides better viewing contrast.

CONCLUSION

With the help of Labview basic timing and addressing features : Announcements, Paper-code ,subject name, Sound recording and RTC Sync signals, Class-room feedback signal Serial communication over cable can be achieved.

Since all the tedious work is handled by Labview, we can use 89V51RD2 microcontroller with ALPHANUMERIC Display which satisfy our requirements.

To make the software flexible and more readable, program for microcontroller side as well as on Labview is rewritten in modular fashion.