In this project we show that how we modify the blind stick for blind person. We convert the normal blind stick into robotic blind stick. In this stick we use five different sensor with microcontroller interface. Here in this project we use ic 89s51 as a main microcontroller to interface the blind stick with the different sensor’s and different sound. Main part of this project is software, software is to be written in assmeblly language and assemble this software in the 8051 assembler. After assemble the software in the assembler we assemble it and then assembler automatically convert this asm file into hex file. Now this hex file is to be transfer into the blank ship with the help of programmer kit. Programmer kit is connect with the computer via serial port and hex file from the computer is to be transfer into the blank chip with the help of this kit. We use a multitime programmable chip, so we use this chip for many time.
In this project we will use voice processor.After each input our voice processor will play the precorded message. We can edit voice message any time. For that we will attach condenser mic with it. IC no is ISPV304 as a voice processor
SENSOR LOGIC:
In this project we use thermistor for the temperature sensor.theremistor sense the excessive heat and then this small change of resistance from thermistor is sense by the controller and buzzer gives a sound.
In light sensor we use LDR, ldr sense a excessive light and due to this light our circuit trigger and alarm is on , on every sensor alarm sound is different. LDR is basically use for a excessive light like, car headlight in night.
Mercury sensor for falling logic, when stick fall on the ground then mercury sensor activate and at this time provide a negative signal to the microcontroller through transistor circuit.
Infra red transmitter and receiver circuit , sense a interruption and when controller sense this interruption then produce a sound. Along with the infra red transmitter we use photodidoe to sense a interruption and controller produce a sound.
Water sense is simply a two conducting wire when sense a water then act automatically and produce a sound from the controller.Our first work of this stick is to be monitor the all the sensor’s if there is any interruption from water, heat light or any thing then jump to specify location automatically for the water sensor we use two metallic plate under the stick , when water touches on this stick then buzzer is on and at this time we set a counter on onlu for one buzzer, so buzzer rings for only one time and stop automatically. But if there is continueous water sensing then buzzer is switch on regularly.
fire sensor: in the fire sensor we we use one thermistor with transistor circuit. With NTC thermistor. When we heat the thermistor then thermistor value is to be decreased and circuit activate and buzzer is on. Note that for all the sensor’s we use negative input to the microcontroller. When microcontroller is on reset position then all the pins are goes high and we program the microcontroller for negative logic. So that from all the sensors we provide a negative input to the microcontroller.
In the light sensor we use ldr as a main sensor. When light fall on the ldr then ldr shows a low resistance and due to that transistor provide a negative signal to the controller. In the light version we provide a 4 time buzzer In the interruption mode we use one infra red led and photodiode in pair. If there is any object in the front of the stick then infra red light is reflected from the object and due to that photodiode gets a negative signal on the controller. When controller sense a negative signal on the pin then processor provide a five time buzzer sound.·
·IR SENSORS FOR ANY PERSON OR VEHICLE DETEC TION – 5MM IR SENSOR WILL BE USED- VOICE PROCESSOR WILL PLAY SOMEONE DETECTED
· LDR – Light dependent resistor FOR ANY CAR COMING LIGHT MODE- VOICE PROCESSOR WILL PLAY CAR DETECTED
· WATER SENSOR FOR WATER DETECTION IN FROM OF BLIND PERSON- SENSOR WILL BE MADE WITH METALLIC STRIPS- VOICE PROCESSOR WILL PLAY WATER DETECTED
· FIRE SENSOR OR HEAT DETECTOR- (THERMOCOUPLE)
Hardware required-
· 8051 programmer universal kit
· CRO 20 Mhz
· Digital multimeter
Software required:
· Keil software- Microvision 2
· ORCAD for PCB design 10.5 Proteus for simulation 7.4 version
Adavantages:
· Low cost- components are not too costly
· Easy available componets