AIM: To control the movement of a manual wheelchair by means of human voice for paralyzed patients. BLOCK DIAGRAM MIC VOICE RECOGNITION IC RESET MICROCONTR OLLER DRIVER CIRCUIT RIGHT MOTOR BATTERY SPEED &DIRECTION CONTROl DRIVER CIRCUIT LEFT MOTOR BATTERY CHARGER SPECIFICATIONS 1.MICROCONTROLLER: ATMEL 89C51 2.VOICE RECOGNITION IC : ISD 2500 3. MOTOR DRIVER CIRCUIT 4.MOTORS(DC):HUB MOTOR 5.BATTERY VOICE RECOGNITION IC •ACCEPTS THE VOICE INPUT SIGNAL •SPEED AND DIRECTION RECORDED MICRO CONTROLLER • PROCESSES DATA • PROVIDES CONTROL VOLTAGE TO MOTORS DC MOTORS •DRIVES THE WHEELS OF THE CHAIR IN NECESSARY MODES VOICE RECOGNITION IC It’s a single chip CMOS voice recognition module 5 -10 isolated word voice can be recognized It compares the input voice signal with the previously recorded signal Insensitive to environmental sounds. Its output serves as a input to microcontroller. MICRO CONTROLLER:ATMEL 89C51 8 Bit CPU optimized for control applications On - Chip Flash Program Memory On - Chip Data RAM Bi-directional and Individually Addressable I/O Lines Multiple 16-Bit Timer/Counters Full Duplex UART On - Chip EEPROM MOTOR DRIVER Control the motor in the forward ,reverse, left & right direction. It consists of four relays. The relay ON and OFF is controlled by the two pairs of switching transistors. MOTOR Electric dc motor is used . It works on the principle of electromagnetism. BATTERY 12volt battery Long life and chargeable ADVANTAGES Compact user friendly less complex. Low cost Easy to implement Accuracy Economical Reduce manpower CONCLUSION Due to the probability of high technology (Atmel microcontroller) used this “Voice operated vehicle” system is fully software controlled with less hardware circuit. The feature makes this system is the base for future systems. FUTURE IDEAS: Powered wheelchair with a speech based interface and biosignal monitoring instrumentation. The user can use the voice, a natural communication method, for controlling the chair movement and obtain information about his health.