State of the art review on walking support system for visually impaired people

The technology for terrain detection and walking support system for blind people has rapidly been improved the last couple of decades but to assist visually impaired people may have started long ago. Currently, a variety of portable or wearable navigation system is available in the market to help the blind for navigating their way in his local or remote area. The focused category in this work can be subgroups as electronic travel aids (ETAs), electronic orientation aids (EOAs) and position locator devices (PLDs). However, we will focus mainly on electronic travel aids (ETAs). This paper presents a comparative survey among the various portable or wearable walking support systems as well as informative description (a subcategory of ETAs or early stages of ETAs) with its working principal advantages and disadvantages so that the researchers can easily get the current stage of assisting blind technology along with the requirement for optimising the design of walking support system for its users

Safe Local Navigation for Visually Impaired Users With a Time-of-Flight and Haptic Feedback Device

This paper presents ALVU (Array of Lidars and Vibrotactile Units), a contactless, intuitive, hands-free, and discreet wearable device that allows visually impaired users to detect low- and high-hanging obstacles, as well as physical boundaries in their immediate environment. The solution allows for safe local navigation in both confined and open spaces by enabling the user to distinguish free space from obstacles. The device presented is composed of two parts: a sensor belt and a haptic strap. The sensor belt is an array of time-of-flight distance sensors worn around the front of a user's waist, and the pulses of infrared light provide reliable and accurate measurements of the distances between the user and surrounding obstacles or surfaces. The haptic strap communicates the measured distances through an array of vibratory motors worn around the user's upper abdomen, providing haptic feedback. The linear vibration motors are combined with a point-loaded pretensioned applicator to transmit isolated vibrations to the user. We validated the device's capability in an extensive user study entailing 162 trials with 12 blind users. Users wearing the device successfully walked through hallways, avoided obstacles, and detected staircases.Andrea Bocelli FoundationNational Science Foundation (U.S.) (Grant NSF IIS1226883

Multimodal perception of histological images for persons blind or visually impaired

Currently there is no suitable substitute technology to enable blind or visually impaired (BVI) people to interpret visual scientific data commonly generated during lab experimentation in real time, such as performing light microscopy, spectrometry, and observing chemical reactions. This reliance upon visual interpretation of scientific data certainly impedes students and scientists that are BVI from advancing in careers in medicine, biology, chemistry, and other scientific fields. To address this challenge, a real-time multimodal image perception system is developed to transform standard laboratory blood smear images for persons with BVI to perceive, employing a combination of auditory, haptic, and vibrotactile feedbacks. These sensory feedbacks are used to convey visual information through alternative perceptual channels, thus creating a palette of multimodal, sensorial information. A Bayesian network is developed to characterize images through two groups of features of interest: primary and peripheral features. Causal relation links were established between these two groups of features. Then, a method was conceived for optimal matching between primary features and sensory modalities. Experimental results confirmed this real-time approach of higher accuracy in recognizing and analyzing objects within images compared to tactile images

Real-Time Obstacle Detection System in Indoor Environment for the Visually Impaired Using Microsoft Kinect Sensor

Any mobility aid for the visually impaired people should be able to accurately detect and warn about nearly obstacles. In this paper, we present a method for support system to detect obstacle in indoor environment based on Kinect sensor and 3D-image processing. Color-Depth data of the scene in front of the user is collected using the Kinect with the support of the standard framework for 3D sensing OpenNI and processed by PCL library to extract accurate 3D information of the obstacles. The experiments have been performed with the dataset in multiple indoor scenarios and in different lighting conditions. Results showed that our system is able to accurately detect the four types of obstacle: walls, doors, stairs, and a residual class that covers loose obstacles on the floor. Precisely, walls and loose obstacles on the floor are detected in practically all cases, whereas doors are detected in 90.69% out of 43 positive image samples. For the step detection, we have correctly detected the upstairs in 97.33% out of 75 positive images while the correct rate of downstairs detection is lower with 89.47% from 38 positive images. Our method further allows the computation of the distance between the user and the obstacles

The Graphical Access Challenge for People with Visual Impairments: Positions and Pathways Forward

Graphical access is one of the most pressing challenges for individuals who are blind or visually impaired. This chapter discusses some of the factors underlying the graphics access challenge, reviews prior approaches to addressing this long-standing information access barrier, and describes some promising new solutions. We specifically focus on touchscreen-based smart devices, a relatively new class of information access technologies, which our group believes represent an exemplary model of user-centered, needs-based design. We highlight both the challenges and the vast potential of these technologies for alleviating the graphics accessibility gap and share the latest results in this line of research. We close with recommendations on ideological shifts in mindset about how we approach solving this vexing access problem, which will complement both technological and perceptual advancements that are rapidly being uncovered through a growing research community in this domain

Review of Machine Vision-Based Electronic Travel Aids

Visual impaired people have navigation and mobility problems on the road. Up to now, many approaches have been conducted to help them navigate around using different sensing techniques. This paper reviews several machine vision- based Electronic Travel Aids (ETAs) and compares them with those using other sensing techniques. The functionalities of machine vision-based ETAs are classified from low-level image processing such as detecting the road regions and obstacles to high-level functionalities such as recognizing the digital tags and texts. In addition, the characteristics of the ETA systems for blind people are particularly discussed

Control for Resonant Microbeam Vibrotactile Haptic Displays

abstract: The world’s population is currently 9% visually impaired. Medical sciences do not have a biological fix that can cure this visual impairment. Visually impaired people are currently being assisted with biological fixes or assistive devices. The current assistive devices are limited in size as well as resolution. This thesis presents the development and experimental validation of a control system for a new vibrotactile haptic display that is currently in development. In order to allow the vibrotactile haptic display to be used to represent motion, the control system must be able to change the image displayed at a rate of at least 30 frames/second. In order to achieve this, this thesis introduces and investigates the use of three improvements: threading, change filtering, and wave libraries. Through these methods, it is determined that an average of 40 frames/second can be achieved.Dissertation/ThesisMasters Thesis Engineering 201

CDI-Type II: Collaborative Research: Cyber Enhancement of Spatial Cognition for the Visually Impaired

Wayfinding is an essential capability for any person who wishes to have an independent life-style. It requires successful execution of several tasks including navigation and object and place recognition, all of which necessitate accurate assessment of the surrounding environment. For a visually-impaired person these tasks may be exceedingly difficult to accomplish and there are risks associated with failure in any of these. Guide dogs and white canes are widely used for the purpose of navigation and environment sensing, respectively. The former, however, has costly and often prohibitive training requirements, while the latter can only provide cues about obstacles in one\u27s surroundings. Human performance on visual information dependent tasks can be improved by sensing which provides information and environmental cues, such as position, orientation, local geometry, object description, via the use of appropriate sensors and sensor fusion algorithms. Most work on wayfinding aids has focused on outdoor environments and has led to the development of speech-enabled GPS-based navigation systems that provide information describing streets, addresses and points of interest. In contrast, the limited technology that is available for indoor navigation requires significant modification to the building infrastructure, whose high cost has prevented its wide use. This proposal adopts a multi-faceted approach for solving the indoor navigation problem for people with limited vision. It leverages expertise from robotics, computer vision, and blind spatial cognition with behavioral studies on interface design to guide the discovery of information requirements and optimal delivery methods for an indoor navigation system. Designing perception and navigation algorithms, implemented on miniature-size commercially-available hardware, while explicitly considering the spatial cognition capabilities of the visually impaired, will lead to the development of indoor navigation systems that will assist blind people in their wayfinding tasks while facilitating cognitive-map development