Sign Language: Flex Sensor

Abstract - Sign language is the mode of communication for the deaf and dumb people with normal person. But the normal person finds difficulty in understanding the sign language. This paper mainly focuses on the deaf and dumb people who are bedridden. It reduces the difficulty faced by the normal people to understand the sign language, by using flex sensor based on hand glove. Flex sensor detects the hand motions depending on the degree of bend. The flex sensor output which indicates the gesture is processed using microcontroller. The identified sign is displayed on the LCD screen, played through speaker and also sent as a message to the mobile phone.

Keywords: Sign language, Flex sensor, Microcontroller, Mobile phone.

I. INTRODUCTION

HARDWARE DESCRIPTION

A. Flex sensor . fig 2: Flex sensor. Flex sensor is otherwise known as bend sensor or variable resistance sensor are resistive carbon parts. When the sensor bends, the output resistance changes. As more the sensor bends, more resistance generates. B. PIC microcontroller PIC16F877A is an 8-bit microcontroller which has an inbuilt RAM, Memory, Internal bus, Peripherals and it uses FLASH memory technology. Some features are 8 channels of 10-bit Analog-to-Digital converter, self programming, 200ns instruction execution, 2 comparators, 250 bytes of EEPROM data memory. It is used to convert the analog output values from the flex sensor to digital form using 10-bit inbuilt ADC module.

C. LCD 16×2 LCD is the basic LCD module. It contains 2 rows in which 16 characters can be displayed. It can be easily interfaced with microcontroller. A microcontroller sends two informations, data and commands to LCD. The data represents the ASCII value of the character which has to be displayed and command represents other operations of the LCD. Data and commands are selected depending on the logic HIGH and logic LOW of the register select (RS) pin of the LCD.

MAX232 MAX232 is used to convert TTL logic level to RS232 logic level for serial communication between microcontroller and GSM modem. The microcontroller operates at 5v where as GSM modem operates at 12v. So, serial communication is difficult to establish between microcontroller and GSM modem. To provide direct link MAX232 act as intermediate link between microcontroller and GSM modem.

IV. RESULTS AND DISCUSSION A communication gap exists between deaf and dumb people and normal people. The communication barrier between deaf and dumb people and the normal person is reduced using this system. Sign language is converted to vocal and textual format using flex sensor and text is also send to the mobile phone. Hence this system converts the sign language into an understandable form for the normal people and detects the hand motions in few seconds. It has got an accuracy of 99%. fig 3: Hardware setup of the system.

V. FUTURE ENHANCEMENT The overall system recognises only a partial sign language in which the gestures are based on the finger movements. Facial expressions is also a part of communication.The future work can be extended to recognise more words and also to capture the facial expressions by employing more flex sensors and MEMS