Voice Recognition Modules

 

Advancement in technology has developed an intelligent man-machine interface technique that facilitates computers or machines or robots to be operated using the voice commands of human without using any input systems, such as keyboards or mouse. This human-machine interface (HMI) can be achieved using voice recognition modules. In this article, we will discuss about the voice recognition modules along with their working procedure and applications.

Voice recognition is a technique that facilitates natural and convenient  human-machine interface using the voice recognition module. It extracts and analyses voice features of human delivered to a machine or computer through the mic. Voice recognition technique is classified into many types based on different criteria such as scope of the users, number of words used for recognition, naturalness of speaking. If the voice recognition level is more than 95%, then only the voice recognition is practically used.

 

 

Voice Recognition Module’s Working Principle

HM2007 is a single chip CMOS voice recognition module. It is an on-chip analog front end large-scale integrated circuit with voice analysis, speech recognition and voice recognition system control processes. HM2007 can be operated in two modes: manual mode and CPU control mode.

In manual mode of operation, the voice recognition module HM2007 is used to build simple recognition system by connecting components such as keypad, SRAM of 8Kbyte memory and other components. If power is on, then the HM2007 starts an initialization process and, if the WAIT pin is L, then the HM2007 checks external memory: 8Kbyte SRAM – whether it is perfect or not. But, if the WAIT is H, then the memory check process will be skipped by the HM2007. After this initialization process, the HM2007 moves into recognition mode. In the recognition mode, if the WAIT pin is H, then the HM2007 is ready to accept the voice and begins recognition process. If the WAIT pin is L, then the HM2007 doesn’t accept the voice that is to be recognized. Then training new pattern by clearing trained pattern are the two operations performed using function keys: TRN and CLR. All the patterns in the HM2007 can be cleared by entering number key 99 and pressing CLR.

In the CPU control mode of operation, several functions such as RECOG, TRAIN, RESULT, UPLOAD, DOWNLOAD, RESET functions of the voice recognition module HM2007 are provided in this mode. Similar to a manual mode of operation, in this mode also power on, recognition, training, resulting, uploading, downloading and reset operations are performed based on different criteria.

Interfacing with Arduino :

Give all the connections as described below.

  • GND – Ground
  • VCC – 5 V
  • RXD – Digital pin 3 of Arduino (This is a user defined pin. Sample code has Pin 3 as Tx.)
  • TXD – Digital pin 2 of Arduino (This is also a user defined pin.)

Arduino Code:

nt redPin = 9;

int greenPin = 10;

int bluePin = 11; byte

com = 0; //reply from voice recognition

void setup() { Serial.begin(9600);

pinMode(redPin, OUTPUT);

pinMode(greenPin, OUTPUT);

pinMode(bluePin, OUTPUT);

delay(2000);

Serial.write(0xAA);

Serial.write(0x37);

delay(1000);

Serial.write(0xAA);

Serial.write(0x21);

}

void loop()

{

while(Serial.available())

{

com = Serial.read();

switch(com)

{

case 0x11:

digitalWrite(redPin, HIGH);

break;

case 0x12:

digitalWrite(greenPin, HIGH);

break;

case 0x13:

digitalWrite(bluePin, HIGH);

break;

case 0x14:

digitalWrite(redPin, HIGH);

digitalWrite(greenPin, HIGH);

digitalWrite(bluePin, HIGH);

break;

case 0x15:

digitalWrite(redPin, LOW);

digitalWrite(greenPin, LOW);

digitalWrite(bluePin, LOW);

break;

}

}

}

Applications of Voice Recognition Module

  • Search for reports or documents on your computer.
  • Create a graph or tables using data.
  • Dictate the information you want to be incorporated into a document.
  • Print documents on request.
  • Start video conferences.
  • Schedule meetings.
  • Record minutes.

 

Reference:

 

https://www.robomart.com/blog/voice-recognition-module-tutorial/

https://www.elprocus.com/voice-recognition-modules-working-procedure-applications/

https://www.nskelectronics.com/voice_recognition_module.html

https://www.rhydolabz.com/arduino-arduino-accesories-c-152_169/voice-recognition-module-p-2309.html