Table of Contents
Introduction:
This project helps blind people to walk toward the destiny, they desired, without any obstacles. Usually, Blind people walk on the path, which is accustomed to them, to avoid any physical damage or injuries done by obstacles coming on the way. So this Blind Aid helps such people to choose any new road and reach their destiny without any tension.
Until well into the twentieth century, most devices developed for measuring distance/movements worked on the same principle; comparison of the measured distance with the standard unit of length. Other advanced means are available now. One of these is the measurement of the time taken by an electromagnetic/sound wave to cover a certain distance. This sound normally lies beyond human hearing and is known as Ultra-sonic waves.
The novel Ultrasonic Movement Detector presented here is suitable for detecting any moving objects within the range between 25 cm and about 6 meters. The detected action is intimated by an alarm sound. Hence this feature is used to help Blind people to reach their destiny safely.
It is built around a matched pair of ceramic transducers, which convert movement energy to electrical energy and vice versa. The operating frequency of the pair is 40kHz. Any movement in the area scanned by the pair of transducers will be detected and a 6V pulse produced. In this Ultrasonic Movement Detector system, the pulse turns on a LED. Pads are provided to take this pulse to add on circuits where it may be used to switch between an automatic reset after the detector has been triggered or to stay triggered. The unit will work reliably up to three meters after calibration.
Block diagram explanation:
Power supply unit
This section needs two voltages viz., +12 V & +5 V, as working voltages. Hence specially designed power supply is constructed to get regulated power supplies.
IR transmitter and Receiver:
Infrared (IR) transmitters and receivers are present in many different devices, though they are most commonly found in consumer electronics. The way this technology works is that one component flashes an infrared light in a particular pattern, which another component can pick up and translate into an instruction. These transmitters and receivers are found in remote controls and all different types of devices, such as televisions and DVD players. Peripheral devices that include this technology can also allow a computer to control various other consumer electronics. Since infrared remotes are limited to line of sight operation.
Temperature sensor:
Thermistors are thermally sensitive resistors whose prime function is to exhibit a large, predictable, and precise change in electrical resistance when subjected to a corresponding change in body temperature. Negative Temperature Coefficient (NTC) Thermistors exhibit a decrease in electrical resistance when subjected to an increase in body temperature and Positive Temperature Coefficient (PTC) thermistors exhibit an increase in electrical resistance when subjected to an increase in body temperature.
Water sensor:
The Water Sensor indicates the presence of water near the module.
Microcontroller:
The Atmel AT89 series is an Intel 8051-compatible family of 8-bit microcontrollers (µCs) manufactured by the Atmel Corporation. Based on the Intel 8051 core, the AT89 series remains very popular as general-purpose microcontrollers, due to their industry standard instruction set, and low unit cost. This allows a great amount of legacy code to be reused without modification in new applications. While considerably less powerful than the newer AT90 series of AVR RISC microcontrollers, new product development has continued with the AT89 series for the aforementioned advantages.
Buffers
Buffers do not affect the logical state of a digital signal (i.e. a logic 1 input results in a logic 1 output whereas logic 0 input results in a logic 0 output). Buffers are normally used to provide extra current drive at the output but can also be used to regularize the logic present at an interface
Drivers
This section is used to drive the relay where the output is the complement of input which is applied to the drive but the current will be amplified
Relays
It is an electromagnetic device that is used to drive the load connected across the relay and the o/p of the relay can be connected to the controller or load for further processing.
Voicebank:
Voicebank is the recording of one’s natural voice for the possible eventuality of losing one’s voice.
Methodology:
In the present scenario if we consider that handicapped people face lots of simple problems in their daily life. So concerning that we have designed this project which consists of different stages which are listed below:
- Traffic signal monitoring system
- Fire detection and water detection with voice announcement.
Further, this project can be enhanced for other applications also.
In the case of a traffic signal monitoring system, the blind person faces the problem that which path of the circle in a traffic area is free to go ahead so to overcome this the transmitters which are placed in the traffic signals will start transmitting the signals whichever is green. Then the receiver module or sensor will start receiving the signal from the respective direction and he or she will come to know which part of the traffic area is clear with the help of voice announcement so that they can take an easy move.
This module has a fire sensor and water sensor to provide voice announcements in case of fire or water detection near the blind person who has this module with him.
Advantages:
- Low power consumption, and compact size,
- Remote signaling lights can be monitored using only one Receiver.
- High reliability, due to the usage of power semiconductor devices,
- Economical in nature, simple in design & operation.
- Highly flexible. The system can be used as a stand-alone unit.
- Due to the digital & analog circuits, the system is highly accurate & automatic.
- As it automatically switches off after one minute, the user can feel the hands-free operation.
Disadvantages:
- One-time investment cost.
- As of now in this project pits cannot be added.
Applications:
- Transmission of signals to concerned person in times of emergency.
- Used in those departments where the number of specialized people is limited.
- This project can be used as a security tool for detecting any possible conditions etc.
- The project can be used in industrial units, Nuclear Plants, Hospitals, etc
