POWERPOINT CONTROL USING GESTURE

MS PowerPoint is very important part of our professional and student life .we face several  problems  while giving the presentation or seminar on some topic like we need an operator to operate the slides and sometimes this will create problems if speaker and operator are not well prepared. To overcome this problem we made the gesture device which can be connected to the computer and operated by the speaker gesture.

The device basically have two part gesture transmitter and computer receiver.

In this device we first recognize the direction of right hand  movement by placing ir sensor on left hand. Then the data is transmitted by the transmitter and the receiver receive the data and give to the computer and one application in  the computer control the ppt. You can download that application here.DOWNLOAD APPLICATION.

HERE IS THE DEMO VIDEO OF THE APPLICATION...

GESTURE TRANSMITTER MODULE: The gesture transmitter Module consist of four different part.

1. IR Sensor Pair

2. LM324 OP-Amp IC.

3. HT12E Encoder IC.

4. RF Transmitter Module

IR sensor principle

As given in block diagram of Gesture transmitter module the IR sensor pair give the data to LM324 which compare the voltage of the IR pair output to the reference voltage and make it to digital. This digital data is further going into the HT12E encoded and transmitted by the Rf transmitter module.

SENSOR: Well I chose two IR sensor for sensing the hand movement on left or right side.on sensig data i can make the decision where to move my power point slide. IR sensor works on the reflection concept when an Infra-red beam is transmit towards an object it should get reflected by that object and that's how we can recognize the hand movement.

IR circuit

Now the circuit  as we can see in the IR circuit that this circuit gives the high voltage output when the less Infra-red rays get reflected back and a low voltage when high reflection of rays occur. For transmitting we have an IR led which work in forward bias condition and at the reception point we use an IR receiver to accept the IR rays and changes the analog voltages according to that.

comparator

From the IR sensor we get the analog data so we have to change that in the digital format like when an object seen than it should return 0v or 4v or in other word's we can say that in high or low voltages because we kno that in digital high voltage = 1 and low voltage= 0. 

comparator data

For the purpose to change the analog voltage into digital we use comparator which compare the analog  voltage to a reference voltage and give a high or low voltage a desired for controller. 

lm324 comparator ic

 The figure shown here is a comparator IC the pin 1,7,8 and 14 are use to give out put to the micro controller. we should connect a reference voltage to the -ve terminal of this IC lm324 and the out put of the IR sensor to its +ve terminal's.

The circuit show below is for your sensor module this is nothing just the summer of what we discuss in sensor subtopic.

IR sensor with comparator circuit

HT12D

ENCODER(HT12E IC): The HT12E is an 4bit encoder which encode the input data applied on it .The pin description of the HT12E is shown in the figure .

• pin (1 to 8) A0-A7 known as address bits so we do not need to consider them.
• pin no (9 and 18) are use to bias the IC  as pin-18 as VCC and pin-9 as GND.
• pin - 17 is connected to the rf transmitter module Din.
• pin-16 and pin-15 are connected by an Osc resistor known as Roscc(1.1 Mohm)
• pin-14 is connected to ground to enable the transmitt.
• pin-13 to pin-10 are known as AD0 to AD3 those having the 4bit data which is required to transmit.

RF TRANSMITTER MODULE(TX):  .The transmitter module is working  on the frequency of 433MHz and is easily available in the market at the cost of 250rs .

RF Transmitter module

• The vcc pin is connected to the +terminal in the circuit.
• The data pin is connected to the HT12E(pin no-17) that is transmitted or we can say that encoded data.
• The next pin is shown in figure is GND that is connected to the ground terminal.
• Now the last pin ANT this is connected to a small wire as an antenna.

Final circuit setup

COMPUTER RECEIVER MODULE: The Computer Receiver module consist different parts.

receier module

As shown in the block diagram RF receiver module get the transmitted signal sended by transmitter and then HT12D decodes that data in four bit digit and given to the ARDUINO board for making an decesion and send to computer via serially. One application is running in the computer which understand the signal sended by Arduino and control the PPT slides while presenting

Hardware Part: - 1.) Computer
                             2.) ARDUINO BOARD
                             3.) HT12D decoder IC
                             4.) RF Receiver module

1.) RF Receiver Module : The RF receiver module will receive the data which is transfered by the Transmitter module. It is also working as similar to the transmitter module-

• Connect the +vcc pin to the 5volt terminal
• Connect the ground pin to the ground terminal 
• The data pin is then connected to the HT12D (pin-14)
• So that we can get the decoded 4 bit data

2.)Encoder(HT12E IC):- It decodes the data is received by the RF receiver module.The input data is decoded when no error or unmatched codes are found. A valid  transmission in indicated by a high signal at VT pin that is pin no 17.

HT12D

• pin 18     : It is use to give the +vcc or biasing to the  IC HT12D this pin is connected with the +5 volt
• Pin 17     : It is the valid transmission pin it will high when the transmission is ok so that we connected this pin to an led for indication.
• Pin 16-15: we connect these two pin directly by a 51k resistor
• Pin 14     : This pin is connected with the rf receiver module data pin to receiving the serial data.
• Pin 10-13: These pins are data pin which is transferred by the Transmitter module.

3.)ARDUINO Board : Arduino is an open-source platform based on avr (atmega series). It’s a combination of easy to use software and hardware environment for electronics student, developer, hobbyists to create interactive devices and environments.

Arduino can be easily interfaced with sensors, controlling led’s , motor driving, relays. The on board  microcontroller is programmed with help of arduino programming language, and arduino development environment.

4.)Computer : Finally the Computer get the data  from the Arduino board and act according to the program one appliationis also need to connect the port to ppt.

Here is the full setup of receiver module.

Software Section:

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ARDUINO PROGRAM written in arduino ide.

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int left_sense=9;    // left sensor pin
int right_sense=8;   // right sensor pin

void setup()
{
  Serial.begin(9600);
  pinMode(left_sense,INPUT);
  pinMode(right_sense,INPUT);
}

void loop()
{
  while(1)
  {
    int left_data = digitalRead(left_sense);    //reading left sensor data
    int right_data = digitalRead(right_sense);  //reading right sensor data
    while(left_data == 1)                       //hand on left sensor 
    {
      left_data = digitalRead(left_sense);
      right_data = digitalRead(right_sense);
      if(right_data == 1)                      // passng through right sensor
      {
        Serial.println("D");
        while(right_data == 1)                // wait to over the swipe
        {
          right_data=digitalRead(right_sense);
        }
      }
    }
    while(right_data == 1)
    {
      left_data = digitalRead(left_sense);
      right_data = digitalRead(right_sense);
      if(left_data == 1)
      {
        Serial.println("B");
        while(left_data == 1)
        {
          left_data = digitalRead(left_sensor);
        }
      }
    }
  }
}
      
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 PC AAPLICATION TO CONTROL PPT.
For downloading the PC application to connect your hardware to PC please CLICK HERE

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