Voice Based Navigation System for Blind People Using Ultrasonic Sensor
As the technology is advancing day to day, the human machine interaction has become a must in our daily life. The interference has progressively become more important and advanced in order to ease the interaction process of the user and provide friendly operation. There are a few advanced technologies which are now accessible in the market to cater the needs, yet they have their own particular drawbacks, thus one of the efficient solutions is to use an embedded system. The primary objective of this work is to permit blind persons to explore autonomously in the outside environment. Ordinary route navigational systems in the outdoor environment are expensive and its manufacturing is time consuming. Blind people are at extensive drawback as they regularly do not have the data which is required, while passing obstacles and dangers. They generally have little information about data such as land marks, heading and self velocity information that is crucial for them to explore them through new environment. It is our conviction that advances in innovations could help and encourage these blind people in their regular operations. This work goes for giving the route to blind persons, by designing a cost – effective and more flexible navigation system. Here we are developing a navigation system that makes use of sounds in order to provide navigation instruction to the user. The conversion of speech into a text is done by a pocket sphinx and Google API, whereas the text to speech conversion is done by Espeak and here we are trying to convert the speech into an Indian language (Hindi). Route navigation is taken care by a Raspberry pi. The route questions queries of the destination location are geocoded utilizing Geo-coder module and then passed to Espeak (text to speech) module to create a pedestrian route. The user can include the location by talking into a microphone connected to raspberry pi. The whole system is mounted to a pack that sits on the client waist. It is light and convenient and it doesn’t obstruct any of the client’s detects while it is being utilized.
There are approximately 38 millions of people across the worldwide mainly in developing countries who are blind and visually impaired, over 15 million are from India. Blind persons most of the time are withdrawn from the society because they feel that people and the society are prejudiced and they may not be welcomed most of the time .The remarkable achievement, which is the outcome of persistent struggle and hard work between “Anne Sullivan” – the teacher and “Helen Keller “-the blind student resulted in a revolutionary method of learning and communication, which ultimately culminated in the development of Braille language. Blind person do not need pity, but require empathy, so as to mingle in the society and be independent for their routine chores (activity).Hence blind people need an assistive device that will allow blind user to navigate freely and this requirement has become crucial. Most of the blind people depend on other individuals, white cane or guide dogs to travel freely. Currently, there are several visual information that helps visually impaired people to move in a right way (e.g. takes a right direction, take left, move forward, move backward and avoid obstacles,) but they all limit the freedom of the user. Walking securely and unhesitatingly with no human help within urban environment is a troublesome undertaking for visually impaired and blind individuals. The fundamental goal is to give an ease or financially savvy approach that will permit visually impaired individuals to explore freely or independently in the outdoor environment. Based on this real context or condition we focused the work on developing assisting technologies that may help blind individuals bringing them back to the society. Our main objective is to make a compact, self-sufficient system that will permit these blind people to travel through an environment .This voice based route navigation system can provide solution to this problem. This System is based on embedded system and provides navigation instructions to the user by giving audio instructions through speaker which is connected to raspberry pi using a USB jack. This navigation system will detect an obstacle using HC-SR 04 ultrasonic sensor and guide blind person by providing an audio instructions through 3.5 mm speakers.
The software’s used in this project includes “embedded c” coding for obtaining GPS data and “python” coding to measure the distance of the object and for obstacle detection .Pocket sphinx and Google API are used for converting the speech to text and Espeak for converting text to speech. Here text to speech synthesis has been used for English and Hindi language. Entire system consists of different modules. This architecture is divided into 6 major modules: Initialization, User Interface, Address query translate, and Route Query, and Route transversal, obstacle detection. Each module plays a distinct a fundamental function. They are described next 1) Initialization: The first step includes initializing the system library. 2) User Interface: Obtain the destination address from user using a microphone, this microphone is connected to a raspberry pi. Here it emphasizes the Voice Module remarking the importance of touch independent and visual independent interfaces as the system is designed especially for blind and partially sighted people. The voice interface implemented uses services such as Text To Speech for the voice outputs and the Google Voice Recognizer API. Text To Speech synthesizes speech from text. It is used whenever there is information to be displayed. A server client approach is followed by voice module, where Voice Recognizer part communicates with the server to processes information and send it back to the user as text. 3) Address query translate: The address query translates geographic to coordinate this includes the geocoding part, converting the destination address into latitude and longitude, this in turn provides the detail information of the destination address the information module comprises all the data related to points of interest outside the building that is outdoor environment. Every location, bus stand, counters, schools, colleges is associated to one specific category, If a visually impaired or blind person wants to go from one place to another place, the database must be predefined .This information must be clear and concise, once it will be used for the selection of services it will be delivered to the user by synthesized speech. 4) Route Query: Route query takes the blind user current Co-ordinate from GPS and the destination Co- ordinate, and compute the routes. The localization module is designed to, constantly monitor the position of a user using GPS module. Different Places have different latitude and longitude hence as the person move from one places to another place the latitude and longitude changes according to the place. As a result of this, many new designs can take the advantage of being tractable. 5) Route transversal: Route transversal provides audible instructions to user in the form of speech so that the blind person can travel independently. Once the destination address is obtained this address must be translated to geographic point. The destination address will be geocoded using the GEO-CODER module and then passed to text to speech synthesizer to generate a pedestrian route.
Overall the project has been a success with the entire project requirement. The future scope for this project is to improve the capabilities by this system by incorporating landmark as saved destination. We would like find a more accurate cost effective GPS receiver as well as faster portable Linux computer. We would also like develop an algorithm for position and velocity so that other methods of navigation such as dead reckoning can be implemented accurately. And to use the online route, for obtaining the route from the Google maps, so that the blind person can travel to the places which are not stored in the database.
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