Abstract. Blindness is the lack of visual perception. Damage to any portion of the eye, the optic nerve or the area of the brain is responsible for the vision that can lead to blindness. People suffering from blindness face many problems while traveling alone. The main aim of this project is to provide a simple user-friendly and effective solution for the visually impaired. The equipment will help the user to be aware of hazards during his/her walking path. The main component of this equipment is the Ultrasonic sensor with a built-in Arduino code. Any obstacle within a specified range of 3 meters can be detected with the help of this equipment. This implemented system is very easy to use, portable and comparatively low-cost solutions for blind and visually impaired men.
I Introduction. Vision is the most important part of human physiology as 83% of the information of human beings gets from the environment through sight. The 2011 statistics by the World Health Organization WHO estimates that there are 285 million people in the world with visual impairment, 39 billion of which are blind and 246 with low vision. The traditional and oldest mobility aids for those with visual impairments are the walking cane also called a white cane or stick and guide dogs. There are huge drawbacks of these aids. Most important of which are the necessary skills and training phase. Moreover, very little information is conveyed. The rapid advancement of modern technology has brought huge development in both hardware and software sectors. These have brought the potential to provide intelligent navigation capabilities. Recently there has been a lot of Electronic Travel Aids ETA designed and devised to help the blind navigate independently and safely. ETA mainly depends on signal processing and sensor technology. Many blind guidance systems use ultrasound because of its immunity to environmental noise. Another reason why ultrasonic is popular is that the technology is relatively inexpensive and also ultrasound emitters and detectors are small enough to be carried without the need for complex circuit. Blind people have used canes as mobility tools for centuries but it is not convenient enough for the blind to travel with. Hence we have proposed a simple design that will help the blind man to move freely without any assistance indoors as well as outdoors.
II Circuit Diagram. The circuit diagram was designed with the equipment we used in our project. III Components Used and the reason of using The system consists of i Ultrasonic Sensor HC SRO4 ii Arduino Uno Board iii 220 Ohm Resistor iv Buzzer v LED optional Description of Components Ultrasonic Sensor HC SRO4. As the name indicates ultrasonic sensors measure distance by using sound waves like bats do to navigate. The sensor head emits an ultrasonic wave and receives the wave reflected back from the target. An optical sensor has a transmitter and receiver whereas an ultrasonic sensor uses a single ultrasonic element for both emission and reception. In a reflective model ultrasonic sensor, a single oscillator emits and receives ultrasonic waves alternately. This enables the miniaturization of the sensor head. It is possible to measure the distance between emission and reception. The reason we used ultrasonic sensors in out circuit is because of its high frequency and high sensitivity. It has a higher sensing distance in cm or inches compare to the inductive proximity sensor. Even the distance can be controlled through proper functioning. The sensor can work in any adverse environment like smoke dust, mist vapor lint, etc needed Arduino Uno Board. The system is equipped with an advanced microcontroller to increase the response speed to make it way easier and to decrease computational complexity. It is a microcontroller board based on the ATmeha328Pю It has 14 digital input-output pins of which 6 can be used as PWM outputs 6 analog inputs a 16 MHz quartz crystal a USB connection a power jack an UCSP header and a reset buttonю It contains everything needed to support the microcontroller simply connect it to a computer with a USB cable or power it with an AC to DC adapter or battery 9V to get it startedю Arduino programs are written in C or C however many of the details are hidden from the user only two functions called by the system need to be defined to make a program continually loops.
The reason we used Arduino Uno is to get the efficiency of advanced microcontroller systemю, In general, a microcontroller is better than another microprocessor to anything that requires sensing of inputs 220 Ohm Resistorю Resistors are what are called Passive Devices that is they contain no source of power or amplification, but only attenuate or reduce the voltage or current signal passing through them. The principal job of a resistor within an electrical or electronic circuit is to resist, hence the name Resistor regulates or to set the flow of electrons current through them by using the type of conductive material from which they are composed. Buzzer. A buzzer or beeper is an audio signaling device which may be mechanical, electromechanical or piezoelectric. Typical uses of buzzers and beepers include alarm devices timers and confirmation of user input such as a mouse click or keystroke.LED. A light-emitting diode. LED is a two-lead semiconductor light source. It is a p n junction diode that emits light when activated. When a suitable voltage is applied to the leads electrons are able to recombine with electron holes within the device releasing energy in the form of photons. IV Result. Our project is designed and configured for practical use. The user will be concerned about how far the obstacle is located. Through the IDE of Arduino uno we have successfully shown the distance between the sensor and the obstacle. Figure a When the safe distance is 30cm Figure b Figure b When the safe distance is 300cm V Graph When the obstacle is too near the graph will go upward. That is to say, the system will provide warning alarm when the user will get too nearer to any obstacle. VI Uses and Applications.
This project has been solely designed for the visually disabled and visually impaired human beings so that they travel easily from one place to another safely without any help of others. The project can be used both indoors and outdoors and even in adverse environment like mist fog smoke etc. The system is capable of identifying any obstacle within a range of 3 metres. Ultrasonic sensors are comparatively low cost and higher usability So the system can provide a low cost and efficient navigation aid for the visually disabled. The user can get a sense of artificial vision as the device is providing him information regarding the environmental scenario around him. The device can work on both smooth and unsmooth surfaces. The device is portable. Hence it is easy to carry Figure c Portable Device VII Challenges. We have used ultrasonic sensor in our project But ultrasonic sensor can detect obstacle in one direction only. In future we hope to add a few more ultrasonic sensors so that the user can easily get aware of any sort of obstacle coming from any direction. Our system is not capable of detecting obstacles like potholes or stairs. The user has to move his hand continuously for now. This problem will be solved after addition of multiple ultrasonic sensors. We wanted to use motor sensor. But motor sensor can detect obstacle within 180. In that case the user will be considered as an obstacle too. So we were unable to use motor sensor. We wanted to use accelerometer sensor. They are low cost can measure inclination tilt and orientation. But in order to identify the pothole the user needs to be on the pothole. We have already used Infrared sensor in our previous circuit But infrared sensor work on flat surfaces only. Their distance range is also short compared to ultrasonic sensor VIII. Conclusion. An attempt has been made in this proposal to help the visually impaired human beings. We have discussed the problems faced by the blind men. Then we have come up with an effective low cost user friendly portable solution. The system is easy to use and user friendly. With further development this project can ensure the safe and secured mobility of the visually impaired people IX REFERENCES 1 Rohit Sheth A smart white cane. An Elegant and Economic Walking Aid 2 www who int mediacentre factsheets fs282 en 3 Shruti Dambhare Prof A Sakhare Smart stick for Blind Obstacle Detection Artificial vision and Real time assistance via GPS 2011 2nd National Conference on Information and Communication Technology NCICT.