30-07-2011, 10:38 AM
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The various systems have been developed to help blind individuals orienting in the surround space, The range of these systems is very wide and stretches from the simplest, inexpensive devices to the complex, multi-component vision systems which transforming the optical camera images into electric signals and transmit them to the cerebral cortex via implanted electrodes. However, these systems are very complex, expensive and are seldom used. The dedicated ultrasonic sensor is reflecting signals for long range nearly 2 meters. While receiving the reflected signal which gives digital output by taking this output to the microcontroller we can Access the voice through voice ic APR9600.By accessing the voice blind people can easily find out the obstacles which are in front of them
The system consist of the ultrasound transmitter TX and receiver RX, the CPU-controlled carrier generator to form the ultrasound carrier signal, the transmitter driver to amplify the carrier signal to the piezoelectric transmitter acceptable levels, the signal mixer to select the Doppler frequency shift during speed measurements, synchronous rectifier to rectify the incoming signal low-pass filter to suppress the high frequency mixer/rectifier products, CPU for system control.
The various systems have been developed to help blind individuals orienting in the surround space, The range of these systems is very wide and stretches from the simplest, inexpensive devices to the complex, multi-component vision systems which transforming the optical camera images into electric signals and transmit them to the cerebral cortex via implanted electrodes. However, these systems are very complex, expensive and are seldom used. The dedicated ultrasonic sensor is reflecting signals for long range nearly 2 meters. While receiving the reflected signal which gives digital output by taking this output to the microcontroller we can Access the voice through voice ic APR9600.By accessing the voice blind people can easily find out the obstacles which are in front of them
The system consist of the ultrasound transmitter TX and receiver RX, the CPU-controlled carrier generator to form the ultrasound carrier signal, the transmitter driver to amplify the carrier signal to the piezoelectric transmitter acceptable levels, the signal mixer to select the Doppler frequency shift during speed measurements, synchronous rectifier to rectify the incoming signal low-pass filter to suppress the high frequency mixer/rectifier products, CPU for system control.
