Design And Construction Of A Sensitive Clap Switch

ABSTRACT

Clap activated switch is an electronics device that can switch on & off a light, Fan, Radio or any other appliance by the sound of clap. This is the system of a very sensitive clap switch. It switches ON/OFF a White LED or electrical appliances through claps. The circuit can sense the sound of claps from a distance of 1-2 meters. Condenser Mic picks up sound vibrations caused by the clap. Whenever there is loud sound produced near the electret condenser mic, pin 2 of 555 gets triggered and it switches on the LED D1. The LED remains on for a definite time determined by R3 and C2. We can adjust the sensitivity of the circuit using a variable resistor in place of fixed resistor R5.

 CHAPTER ONE

1.0                                                        INTRODUCTION

1.1                                                  PROJECT BACKGROUND

In the present modern world, switching circuits have become an indispensible part of our life. Right from your mobile phone to the various security systems, they can be seen everywhere. Even the horn of your motor car is a kind of switch used to warn people and vehicles in front of its presence. The sole purpose of an switch is to activate or deactivate a device. They may be in the form of a visual indicator, for example a flashing light, but switching circuit in the form of an audible tone or siren is more widely accepted as it is able to wake up even the unaware and the oblivious. This work is on sound activated switch. Clap activation or deactivation switching is all about automating real life devices using clap signals.
The word “switch” is a very common name found in almost all aspects electrical/electronic engineering. Switches can be found in information technology computers, telecommunications, power electronics, power systems, instrumentation etc.  They have been defined by various people or organizations in different ways. Some of the definitions of switches are listed below;

• As a device that is used to break or stop the flow of charges in a circuit.
• As a device used to connect two or more computers together
• A device used to interrupt the flow of electrons in a circuit.

All the above definitions are correct, but for this project we are going to define a switch as a device which can be used to control the action of an electrical load, by allowing or obstructing the flow of the electrical signal sent it.

1.2                                          STATEMENT OF THE PROBLEM

• In the industries like the petroleum or chemical industries, some production processes have been started or stopped due to accidental switching of machinery leading to injury or death. This can cause financial strain on a company.
• In the radioactive process, manual switching poses great health hazards to the operator due to the side effects of exposure to the radioactive elements.
• Manual switching is an uphill task for the disabled and the aged due to movement constraints.
• Sometimes, we are victims of electric shocks from our devices when we try to switch them ON/OFF due to leaking currents from the electric switches

  3   PROJECT MOTIVATION

The motivation of this project is to fulfill the following;

• To eliminate the stress in walking from end to end, or room to room of a building to switch devices ON/OFF.
• The provision of remote switching helps to safe guard operators and equipment.
• To ensure a reliable and safe method of switching domestic and industrial devices.

1.4                                             OBJECTIVE OF STUDY

The objective of this project is to construct a device which can be switched on and off using clap signals.  This unit is very sensitive to sounds and disturbances, received within a microphone capsule and refined, take action on a relay.

1.5                                                          SCOPE OF THE PROJECT

The scope of this work is defined by the following points

1. The switching interface in this project is of the general purpose type as it is not restricted to only one type of load.
2. The clap signal accepted by the computer, will not be limited to just one person.

III.      It will not be limited to low voltage, low current AC/DC applications of 240V maximum operating voltage.

1. The type of control this project employs is the simple ON/OFF control of devices

1.6                                        SIGNIFICANCE OF PROJECT

This project’s completion will be of great benefit to our ever demanding and developing society. Some of these benefits include;
I.  Accidental switching of devices will be reduced to a minimum in our industries and homes.

1. Walking from point to point to switch switches will be a thing of the past.
   III.      This project will possess the LOCK and UNLOCK functions, which will prevent unintentional switching any time the user wishes
   VI.      Our industries and homes will become friendlier to disabled people.