IJERT-Feasibility Study of a Navigation Aid System for The Visually Impaired (original) (raw)

Low-cost stereo vision system for supporting the visually impaired's walk

2009

This paper presents an obstacle detection system for the visually impaired to use with a walking stick. The system in this work can find obstacles applying the depth discontinuities Pixel-to-Pixel (P2P) stereo algorithm which is one of the Intensity-based Stereo Matching (ISM) techniques in stereo vision that can find objects with featureless surface such as whiteboard, door, etc. However, the ISM technique is time consuming and not fast enough for real-time usage. Applying parallel computing using Message Passing Interface (MPI) helps reduce the computing time and enables realtime usage. In this work, we estimate the distance between objects and the visually impaired by applying the V-disparity. Our system can accurately detect objects within the range of 5 meters using 12-centimeter based-line low-cost webcams.

Obstacle Detection using Stereo Imaging to Assist the Navigation of Visually Impaired People

Procedia Computer …, 2012

Assistive technology enables people to achieve independence when performing daily tasks and it enhances their overall quality of life. Visual information is the basis for most navigational tasks, so visually impaired individuals are at disadvantage due to the lack of sufficient information about their surrounding environment. With recent advances in inclusive technology it is possible to extend the support given to people with visual disabilities in terms of their mobility. In this context we propose and describe the Blavigator project, whose global objective is to assist visually impaired people in their navigation on indoor and outdoor environments. This paper is focused mainly on the Computer Vision module of the Blavigator prototype. We propose an object collision detection algorithm based on disparity images. The proposed algorithm uses a 2D Ensemble Empirical Mode Decomposition image optimization algorithm and a two layer disparity image segmentation to detect nearby objects.

Object Distance Measurement by Stereo VISION

2013

The 3D camera consists of two cameras of parallel optical axes and separated horizontally from each other by a small distance and these two cameras are combined together in a single frame. The 3D camera is used to produce two stereoscopic pictures for a given object. The distance between the cameras and the object can be measured depending upon the distance between the positions of the objects in both pictures, the focal lengths of both cameras as well as the distance. Triangulation is used to relate those mentioned dimensions with each other. Image processing is used to determine relations between the pictures of the object in the images formed by left and right camera through the technique of template matching. Template matching is used to find similarity between parts of the two images containing the object picture, which lead to find the amount of disparity in the object position coordinates. The distance of the object varies inversely with disparity and the accuracy of distance...

Automatic Calibration of Stereoscopic Cameras in an Electronic Travel Aid for the Blind

Metrology and Measurement Systems, 2013

The article describes a technique developed for identification of extrinsic parameters of a stereovision camera system for the purpose of image rectification without the use of reference calibration objects. The goal of the presented algorithm is the determination of the mutual position of cameras, under the assumption that they can be modeled by pinhole cameras, are separated by a fixed distance and are moving through a stationary scene. The developed method was verified experimentally on image sequences of a scene with a known structure.

Distance Measurement Using Stereo Vision

2017

In this paper, we propose a novel concept of relative distance measurement using Stereo Vision Technology and discuss its implementation on real-time image processor. We capture two images using two CCD cameras and compare them. Distance is calculated for the object using a mathematical calculation using matlab algorithm. This algorithm is based on the concept of the triangulation method for distance (Proved Later), we can thus get the relative distances of objects in front of the camera. The output is displayed on a Computer screen in the form of a distance image. This system works in real time on a full PAL frame rate (720 x 576 active pixels)

A Stereovision System for 3-D Perception

Elektronika Ir Elektrotechnika, 2015

The results of investigation on a stereovision system for 3-D perception are presented. A 3-D space data can be reconstructed from a pair of 2-D images, the basis of stereo vision and computation equations are given. Also error of depth estimation and ways to minimise it are surveyed. The systems’ hardware design and the ways to synchronise cameras to avoid incorrect map reconstruction due to asynchronous frame capturing are presented. The results of experimental investigation: measured and extrapolated distances at certain disparities using 6 mm and 2.5 mm lenses, error of distance measurement distribution are presented. The results show that usage of longer focus lenses is more useful at long range perception. Also the results show that the system surveyed is suitable for autonomous robot navigation system. Ill. 7, bibl. 8 (in English; summaries in English, Russian and Lithuanian).

Stereo vision in blind navigation assistance

World Automation …, 2010

Visual impairment and blindness caused by infectious diseases has been greatly reduced, but increasing numbers of people are at risk of age-related visual impairment. Visual information is the basis for most navigational tasks, so visually impaired individuals are at disadvantage because appropriate information about the surrounding environment is not available. With the recent advances in inclusive technology it is possible to extend the support given to people with visual impairment during their mobility. In this context we propose a system, named SmartVision, whose global objective is to give blind users the ability to move around in unfamiliar environments, whether indoor or outdoor, through a user friendly interface. This paper is focused mainly in the development of the computer vision module of the SmartVision system.

Stereo Vision for Visual Object Tracking and Distance Measurement Assessment

Journal of Mechanical Engineering

The computer vision for binocular eyes system has many applications in robot applications and safety purposes. Based on the previous research, the combination of the area of sight of stereo vision will trigger the trigonometry intersection point for determine the distance of the objects from it baseline. The system programme codes is one of the issue need to confront consequent since there are various sorts of calculation that are in the same field, however has unmistakable of use. This project focuses on how to measure distances using binocular vision. The main objective is to evaluate the binocular vision system by calculating the distance of objects in real environment. Furthermore, the project proposes a new program algorithm for binocular vision system to work, in order to identify distance of an object with a basic equation has been derived and set in the designed algorithm. The setting environment are set to single and multi-objects measured, object in environment and changes...

Stereo disparity estimation algorithm for blind assisting system

2012

The ability to explore unknown spaces independently, safely and efficiently is one of the challenging aspects of any blind assisting system. Many of the known existing electronic travel aids do not reveal spatial information to the blind. Therefore in this paper the focus is on obtaining the spatial information with the help of image processing techniques. Different disparity estimation algorithms are studied in order to arrive at a scheme specifically suitable for the blind. Real time images are captured by a pair of image sensors and the proposed algorithm will determine the surface conditions such as curbs, stair case and other general obstacles encountered on the navigational path.

Matching segments in stereoscopic vision

IEEE Instrumentation & Measurement Magazine, 2001

W e have built a stereoscopic sensor and implemented algorithms that obtain 3D coordinates of objects from images. This system aids localization and the navigation of a mobile robot. The sensor uses two small cameras oriented vertically to form a stereoscopic vision system for the mobile robot. We show that it is possible to match segments from the top and bottom images without using an epipolar constraint.