Blind Travelers Research Articles

All the Way There and Back: Inertial-Based, Phone-in-Pocket Indoor Wayfinding and Backtracking Apps for Blind Travelers

All the Way There and Back: Inertial-Based, Phone-in-Pocket Indoor Wayfinding and Backtracking Apps for Blind Travelers

Experiments with RouteNav, A Wayfinding App for Blind Travelers in a Transit Hub.

RouteNav is an iOS app designed to support wayfinding for blind travelers in an indoor/outdoor transit hub. It doesn't rely on external infrastructure (such as BLE beacons); instead, localization is obtained by fusing spatial information from inertial dead reckoning and GPS (when available) via particle filtering. Routes are expressed as sequences of "tiles", where each tile may contain relevant points of interest. Redundant modalities are used to guide users to switching goalposts within tiles. In this paper, we describe the different components of RouteNav, and report on a user study with seven blind participants, who traversed three challenging routes in a transit hub while receiving input from the app.

Short‐term traffic travel time forecasting using ensemble approach based on long short‐term memory networks

AbstractTo enhance the control effect of intelligent transportation system (ITS) of expressway, avoid blind travel causing traffic congestion, improve road capacity, and achieve the purpose of smooth and efficient operation of the network, 3σ criterion and 2σ cycle removal criterion were used to eliminate the abnormal data of travel time. Thereafter, a combined prediction model of Long Short‐Term Memory (LSTM) based on the complete ensemble empirical mode decomposition with adaptive noise (CEEMDAN) algorithm and attention mechanism is proposed. Travel time data, collected from the real world, is decomposed into several Intrinsic Mode Functions (IMFs) and a residue with the CEEMDAN. Then, the decomposed sub‐sequence is predicted and the final prediction result is obtained by comprehensive superposition. The results indicate that: the CEEMDAN algorithm has significantly improved the prediction performance. Compared with the AT‐LSTM model, mean absolute percentage error (MAPE) is reduced by 10.75%, 24.84%, 31.80%, 24.98%, 14.29%, and 31.42% when the time window was 3, 6, 9, 12, 15, and 18, respectively, in the dataset of Yaxi expressway. In the dataset of Chengnan expressway, the number of error points with MAPE greater than 40% is significantly reduced after the adoption of the LSTM model. After the introduction of CEEMDAN algorithm, the error at each time point is controlled within 30%. The proposed model controls the error at each time point within 25%. In different datasets, the proposed model has better prediction ability for highly non‐linear travel time, and can better capture the trend abrupt characteristics of rush hour traffic flow.

The Cost of Knowing: How Obstacle Alerts Reduce Walking Speeds of Augmented White Cane Users

To ensure safe passage blind travellers utilize mobility aids such as the white cane to preview the space their body will move through. Augmented white canes (AWC) have increased this preview range to reduce collisions, but consequently incurred lower walking speeds. The literature has blamed the slowdown on the AWC provided alerts that are additional to white cane feedback, unnecessary, too complex, and the anticipatory slowdown of their users. Two within-subject studies with six visually impaired and ten blindfolded people compared the white cane to two different AWC preview types (See Figure 1) combined with two ranges to investigate the causes of the slowdowns. The cognitive cost from processing AWC additional and unnecessary alerts and their complexity slowed users down and should be kept to a minimum as they neither helped reduce collisions nor physically detecting obstacles with the cane.

Beyond the Cane: Describing Urban Scenes to Blind People for Mobility Tasks.

Blind people face difficulties with independent mobility, impacting employment prospects, social inclusion, and quality of life. Given the advancements in computer vision, with more efficient and effective automated information extraction from visual scenes, it is important to determine what information is worth conveying to blind travelers, especially since people have a limited capacity to receive and process sensory information. We aimed to investigate which objects in a street scene are useful to describe and how those objects should be described. Thirteen cane-using participants, five of whom were early blind, took part in two urban walking experiments. In the first experiment, participants were asked to voice their information needs in the form of questions to the experimenter. In the second experiment, participants were asked to score scene descriptions and navigation instructions, provided by the experimenter, in terms of their usefulness. The descriptions included a variety of objects with various annotations per object. Additionally, we asked participants to rank order the objects and the different descriptions per object in terms of priority and explain why the provided information is or is not useful to them. The results reveal differences between early and late blind participants. Late blind participants requested information more frequently and prioritized information about objects' locations. Our results illustrate how different factors, such as the level of detail, relative position, and what type of information is provided when describing an object, affected the usefulness of scene descriptions. Participants explained how they (indirectly) used information, but they were frequently unable to explain their ratings. The results distinguish between various types of travel information, underscore the importance of featuring these types at multiple levels of abstraction, and highlight gaps in current understanding of travel information needs. Elucidating the information needs of blind travelers is critical for the development of more useful assistive technologies.

Blind Travel Prediction Based on Obstacle Avoidance in Indoor Scene

Blind people have intelligent tools to rely on for travel with the development of navigation technology. The GPS navigation, blind track, etc., are tools that blind people often use when traveling outdoors. However, indoor navigation tools and technology for blind people are lacking. We propose an obstacle avoidance algorithm and a spatial‐temporal model of trajectory prediction for the indoor travel task of the blind. The focus of this work is that it enables the blind to accurately avoid obstacles and achieve high accuracy trajectory prediction aiming at the unique movement characteristics of the blind. We set up a variety of baselines to conduct an experimental evaluation on a dataset of blind trajectories in a multistorey shopping mall. The experimental results show the advantages of the data model and predictive model of this work.

Use of an Indoor Navigation System by Sighted and Blind Travelers

This article first reviews the pros and cons of current accessible indoor navigation systems and then describes a study using commercial smart devices to navigate routes through a complex building. Our interest was in comparing performance when using real-time narrative descriptions (system-aided condition) vs. a memory-based condition where the same narrative information was only provided to users from the route's origin. We tested two groups of blind and visually impaired (BVI) users, including people above and below 60 years of age, as well as a third sighted control group. Evaluating older BVI participants is important, as the majority of vision loss is age-related, yet navigation performance using access technology is rarely studied with this demographic. Behavioral results demonstrated that access to real-time (system-aided) information led to better navigation accuracy and greater confidence by blind users compared to the information-matched memory condition. Performance for blind participants over 60 years old was nearly identical with their younger peers—an important outcome supporting the efficacy of using navigational technologies by this fast-growing population. Route completion accuracy and requests for assistance did not reliably differ between blind and sighted participants when using the system, suggesting that access to narrative route information led to functionally equivalent navigation behavior, irrespective of visual status. Survey results revealed strong user support for real-time information and provided important guidance for future interface refinements.

Usability evaluation of foot-based interfaces for blind travelers

Together with sight and hearing, touch represents a means of communication for human beings. Indeed, the sense of touch is capable of proving a whole non-verbal language that can be developed and offer many more possibilities than traditionally believed. Much of what is found in the literature about tactile communication concerns tactile stimulation of the fingertips and hands. However, as the area of tactile feedback is a `hot' research topic especially in human-computer interaction, other body areas have been explored as well; wrist/forearm [1], abdomen [2], chest [3], tongue [4], ears [5], and head [6] have been studied to transmit information to a user (a comprehensive survey of wearable tactile devices can be found in [7]). Devices are as diverse as the technology used and the location on the body. Yet, the human foot has not received much attention.

Mind your crossings: Mining GIS imagery for crosswalk localization.

For blind travelers, finding crosswalks and remaining within their borders while traversing them is a crucial part of any trip involving street crossings. While standard Orientation & Mobility (O&M) techniques allow blind travelers to safely negotiate street crossings, additional information about crosswalks and other important features at intersections would be helpful in many situations, resulting in greater safety and/or comfort during independent travel. For instance, in planning a trip a blind pedestrian may wish to be informed of the presence of all marked crossings near a desired route. We have conducted a survey of several O&M experts from the United States and Italy to determine the role that crosswalks play in travel by blind pedestrians. The results show stark differences between survey respondents from the U.S. compared with Italy: the former group emphasized the importance of following standard O&M techniques at all legal crossings (marked or unmarked), while the latter group strongly recommended crossing at marked crossings whenever possible. These contrasting opinions reflect differences in the traffic regulations of the two countries and highlight the diversity of needs that travelers in different regions may have. To address the challenges faced by blind pedestrians in negotiating street crossings, we devised a computer vision-based technique that mines existing spatial image databases for discovery of zebra crosswalks in urban settings. Our algorithm first searches for zebra crosswalks in satellite images; all candidates thus found are validated against spatially registered Google Street View images. This cascaded approach enables fast and reliable discovery and localization of zebra crosswalks in large image datasets. While fully automatic, our algorithm can be improved by a final crowdsourcing validation. To this end, we developed a Pedestrian Crossing Human Validation (PCHV) web service, which supports crowdsourcing to rule out false positives and identify false negatives.

Pigmentocracies: Ethnicity, Race, and Color in Latin America

Pigmentocracies: Ethnicity, Race, and Color in Latin America

6-DOF Pose Estimation of a Robotic Navigation Aid by Tracking Visual and Geometric Features.

This work was motivated by the limitations of the existing navigation technology for the visually impaired. Most of the existing methods use a point/line measurement sensor for indoor object detection. Therefore, they lack capability in detecting 3D objects and positioning a blind traveler. Stereovision has been used in recent research. However, it cannot provide reliable depth data for object detection. Also, it tends to produce a lower localization accuracy because its depth measurement error quadratically increases with the true distance. This paper suggests a new approach for navigating a blind traveler. The method uses a single 3D time-of-flight camera for both 6-DOF PE and 3D object detection and thus results in a small-sized but powerful RNA. Due to the camera's constant depth accuracy, the proposed egomotion estimation method results in a smaller error than that of existing methods. A new EKF method is proposed to integrate the egomotion into the RNA's 6-DOF pose in the world coordinate system by tracking both visual and geometric features of the operating environment. The proposed method substantially reduces the pose error of a standard EKF method and thus supports a longer range navigation task. One limitation of the method is that it requires a feature-rich environment to work well.

Effect of Cane Technique on Obstacle Detection with the Long Cane

Modern long cane (also known as the white cane) techniques have changed little since their development in the 1940s. The two-point touch and the constant-contact techniques are the two used most widely by travelers who are blind. Regardless of which technique is used, obstacle detection, a key component of preview offered by a long cane (Blasch, La Grow, & De l'Aune, 1996), is crucial for the safety of blind travelers. When obstacles such as construction cones or toys left on the sidewalk are missed, they may trip the cane user, resulting in falls and consequent fall-induced injuries. Several recent studies have examined how different factors affect drop-off detection with the long cane. Cane users detected drop-offs more reliably when they used the constant-contact technique than when they used the two-point touch technique, particularly if they were inexperienced cane users respectively (Kim, Wall Emerson, & Curtis, 2009; Kim, Wall Emerson, & Curtis, 2010a). Younger cane users and those with earlier-onset visual impairments detected drop-offs better than older cane users and those with later-onset visual impairments (Kim, Wall Emerson, & Curtis, 2010b). However, drop-off detection performance with a standard marshmallow tip was similar to that with a marshmallow roller tip (Kim, Wall Emerson, & Curtis, 2010c). In addition, a cane length difference of 10 inches did not result in a significant difference in drop-off detection (Kim & Wall Emerson, 2012). In respect to obstacle detection, La Grow, Blasch, and De l'Aune (1997a) reported that participants achieved the greatest detection distance for foot-level objects (those that are not higher than the ankle) when the hand holding the cane was held at the midline and positioned below the waist. In another study, La Grow, Blasch, and De l'Aune (1997b) also documented that the two-point touch technique did not provide consistent surface previewing for four of seven participants. Wall and Ashmead (2002) found that pivoting the wrist when swinging the cane resulted in better body coverage than did moving the whole arm. The reliability of traditional cane techniques for detecting obstacles is of particular interest because some of the previous studies reported path coverage rates that were inadequately low (61-69%) when the participants used the two-point touch technique (Uslan, 1978; Wall & Ashmead, 2002). Although one orientation and mobility (OM La Grow & Long, 2011). What is of additional interest is whether the constant-contact technique indeed has an advantage over the two-point touch technique in detecting low obstacles. Such claims have been made by many cane users based on the fact that the cane tip stays in contact with the walking surface at all times when the constant-contact technique is used. However, these claims have been solely based on anecdotes and have not been examined empirically. The purpose of the present study was to examine how reliable the traditional cane techniques are for detecting obstacles and whether the type of cane technique affects obstacle detection as it interacts with the height of the obstacles. [FIGURE 1 OMITTED] METHOD Study design and recruitment criteria A repeated-measures design with block randomization was used for the study. We recruited 14 sighted students (7 female and 7 male) aged 22 to 62 (median age = 26) from Western Michigan University's (WMU) O&M program. The participants were familiar with both the two-point touch and the constant-contact techniques and their cane use experience ranged from one month to four months (median experience = four months). …

Toward Blind Travel Support through Verbal Route Directions: A Path Inference Algorithm for Inferring New Route Descriptions from Existing Route Descriptions

The work presented in this article continues our investigation of such assisted navigation solutions where the main emphasis is placed not on sensor sets or sensor fusion algorithms but on the ability of the travelers to interpret and contextualize verbal route directions en route. This work contributes to our investigation of the research hypothesis that we have formulated and partially validated in our previous studies: if a route is verbally described in sufficient and appropriate amount of detail, independent VI travelers can use their O&M and problem solving skills to successfully follow the route without any wearable sensors or sensors embedded in the environment. In this investigation, we temporarily put aside the issue of how VI and blind travelers successfully interpret route directions en route and tackle the question of how those route directions can be created, generated, and maintained by online communities. In particular, we focus on the automation of path inference and present an algorithm that may be used as part of the background computation of VGI sites to find new paths in the previous route directions written by online community members, generate new route descriptions from them, and post them for subsequent community editing.

Toward a computer vision-based wayfinding aid for blind persons to access unfamiliar indoor environments

Independent travel is a well known challenge for blind and visually impaired persons. In this paper, we propose a proof-of-concept computer vision-based wayfinding aid for blind people to independently access unfamiliar indoor environments. In order to find different rooms (e.g. an office, a lab, or a bathroom) and other building amenities (e.g. an exit or an elevator), we incorporate object detection with text recognition. First we develop a robust and efficient algorithm to detect doors, elevators, and cabinets based on their general geometric shape, by combining edges and corners. The algorithm is general enough to handle large intra-class variations of objects with different appearances among different indoor environments, as well as small inter-class differences between different objects such as doors and door-like cabinets. Next, in order to distinguish intra-class objects (e.g. an office door from a bathroom door), we extract and recognize text information associated with the detected objects. For text recognition, we first extract text regions from signs with multiple colors and possibly complex backgrounds, and then apply character localization and topological analysis to filter out background interference. The extracted text is recognized using off-the-shelf optical character recognition (OCR) software products. The object type, orientation, location, and text information are presented to the blind traveler as speech.

Sensory Augmentation for the Blind

Common navigational aids used by blind travelers during large-scale navigation divert attention away from important cues of the immediate environment (i.e., approaching vehicles). Sensory augmentation devices, relying on principles similar to those at work in sensory substitution, can potentially bypass the bottleneck of attention through sub-cognitive implementation of a set of rules coupling motor actions with sensory stimulation. We provide a late blind subject with a vibrotactile belt that continually signals the direction of magnetic north. The subject completed a set of behavioral tests before and after an extended training period. The tests were complemented by questionnaires and interviews. This newly supplied information improved performance on different time scales. In a pointing task we demonstrate an instant improvement of performance based on the signal provided by the device. Furthermore, the signal was helpful in relevant daily tasks, often complicated for the blind, such as keeping a direction over longer distances or taking shortcuts in familiar environments. A homing task with an additional attentional load demonstrated a significant improvement after training. The subject found the directional information highly expedient for the adjustment of his inner maps of familiar environments and describes an increase in his feeling of security when exploring unfamiliar environments with the belt. The results give evidence for a firm integration of the newly supplied signals into the behavior of this late blind subject with better navigational performance and more courageous behavior in unfamiliar environments. Most importantly, the complementary information provided by the belt lead to a positive emotional impact with enhanced feeling of security. The present experimental approach demonstrates the positive potential of sensory augmentation devices for the help of handicapped people.

Evaluation of emergency egress information for persons who are blind

Emergency procedures vary according to the type and extent of emergency, size of building, occupancy and type of building construction. There is no agreement on how emergency egress information should be provided for persons who are blind. This research investigated the efficacy of a Braille (Brl) sign, a Raised Print (RP) sign, a Tactile Map (TM), an audible route description activated by a pushbutton and exit signs equipped with Remote Infrared Audible Signage (RIAS) for enabling persons who are blind to travel routes to exits. The efficacy of each format in terms of time to acquire route information and time to travel a route was measured. Blind travellers' perceived needs and desires for obtaining emergency egress information were also investigated. Both RIAS and pushbutton-activated verbal route directions enabled participants to access and use emergency egress information efficiently. Auditory information was preferred above tactile information. Of the tactile formats, Brl resulted in more efficient access to egress information than RP and TMs and was preferred. This research is a first step in addressing the complex issues involved in providing emergency egress information to persons who are blind.

A New Path Estimation Strategy for Predicting Blind Persons′ Motion in Indoor Environments

Research on the characteristics of spatial cognition without vision is used to improve the design of indoor environments to be safer for blind and visually handicapped persons. A fuzzy cognitive map (FCM) decision mechanism is presented for modeling path planning strategies adopted by blind travelers including wall-following, and shortcutting through the environment. A statistical case based reasoning (CBR) strategy is introduced for anticipating the points of switch between the two mentioned behaviours along the path. The combination of CBR and FCM modules provided a robust model of decision making which can be used for predicting blind motions. In this research, 51 eye-masked subjects contributed for obtaining the path patterns and for validating the results obtained using the proposed path prediction approach.

The "Deaf Traveller," the "Blind Traveller," and Constructions of Disability in Nineteenth-Century Travel Writing

1833 , Penny Magazine published a series of articles about eastern travel. theme was standard, but its heading was not: entitled The Traveller, articles were written by John Kitto ( 18041854) , son of a Cornish stonemason. In 181 7, carrying slates up to roof for his father, young Kitto fell off ladder, an accident which left him totally deaf. After spending several years in workhouse, Kitto became a missionary in Malta, joined an expedition to Persia, and eventually became a tutor for two English boys in Baghdad (they addressed him in finger alphabet, and he spoke back). Upon his return to England, he began publishing essays and reviews, gradually making a name for himself as a writer specializing in popular accounts of biblical studies. * title of Kitto 's series was eye-catching, yet, as many readers in 1830s would have instantly recognized, Deaf Traveller merely followed in footsteps of a more celebrated voyager: James Holman, known as Blind Traveller (1786-18^7). Born in Exeter, son of an apothecary, Lieutenant Holman lost his eyesight at age of twenty-five while serving in Royal Navy. Despite his blindness, he embarked on an ambitious succession of tours around world, publishing several successful travel accounts in 1820s and 1830S.2 Although there is no indication that two men ever met in person, Kitto 's work often referred to Holman 's experiences. Their first textual encounter occurred in 1834, when Kitto was commissioned by Charles Knight (the publisher who initiated DeafTraveller articles) to review Holman s mammoth four-volume A Voyage Round World for of his educational publications. Mr Knight gave me that job, Kitto explained, because he saw a peculiar fitness in a deaf traveller reviewing a blind one (Ryland 364). Recalling episode in his autobiography, Knight revelled in fact that the world is to be now indebted to two Devonshire men for information it is to receive of distant

This Mattered to Me

Impact of Curb Ramps on Safety of Persons Who Are Blind, by Billie Louise Bentzen and Janet M. Barlow, published in July-August 1995 issue of Journal of Visual Impairment & Blindness, Volume 89, Number 4, pp. 319-328. opportunity to contribute to This Matters to Me made me stop and reflect on--and appreciate--how publications such Journal of Visual Impairment & Blindness (JVIB) have affected me and my professional life. The article I selected to highlight in this essay, Impact of Curb Ramps on Safety of Persons Who are Blind, by Billie Louise Bentzen and Janet Barlow, published results of research that was specifically designed to answer a controversial question. Why should that article still matter, years after question was answered and we, a field, have moved on? Because this article represents first time I remember reading orientation and mobility (O&M) research that questioned what we all know to be and because research in article helped settle a passionate argument. article matters even more because it was designed to do more than answer a specific question, it also provided valuable information that changed how I teach. Above all, it inspired me to consider importance of using research to answer questions. To convey significance of this article, a bit of background information is needed. In 1991, there was a heated debate among members of field of visual impairment and blindness about detectable warnings at curb ramps. One side argued that installing them was humiliating, because such ramps implied that blind people are not capable of detecting curbs when, in fact, as knows, blind people can be safe travelers long they have received proper O&M training. The other side argued that, as knows, even with best training, blind travelers have problems recognizing where edges of streets are when there are ramps. The debate was impassioned, with each side citing obvious. QUESTIONING ASSUMPTIONS WITH RESEARCH THAT USES REAL-LIFE SETTINGS While argument over curb ramps raged, and dignity and safety of blind people hung in balance, Beezy Bentzen and Janet Barlow began to design research to address this issue. The idea of using research to study what we all assumed to be true, to settle arguments with facts instead of anecdotes and advocacy, was a revelation to me. Whenever I thought of research, I imagined labs and controls, bells, buzzers, and stopwatches, but Dr. Bentzen and Ms. Barlow thought of real life--real people doing real things, with a minimum of manipulation from researchers. For example, because they were only interested in what happens when blind people walk along curb ramp, they considered having subjects guided toward street to be sure they walked along ramp. But they realized that this would remove some of real-life variables, because a lot of information and cues individuals use to find edge of street can be detected long before they reach curb ramp. The authors were wise to realize that subjects needed to be allowed to engage in whatever approach they would normally take they draw near to a street corner. Since this article was published, I have read other research that questions the truth, such Duane Gemschat and Shirin Hassan's groundbreaking study on whether drivers stop to allow people with white canes to cross roads everyone knows they do (Gemschat & Hassan, 2005). …

Traveling by Touch: How Useful are Tactile Maps?

Many of you who are reading this article are itinerant professionals. To do your job, you make daily use of your own car, public transportation, or perhaps a contracted car and driver. If you drive your own car, you probably have caches of maps in accessible places to help you plan your travel. In my car, the maps use often are in the driver's side pocket, and the rarely used ones are nested in the glove compartment. If you are an aging baby boomer as am, you may also keep a magnifier for reading Mine is clamped on the driver's side visor, and occasionally when drive over a bump in the road, am startled by the magnifier dropping suddenly into my lap. If you are blind or have low vision, your travel planning is somewhat different. Rather than reaching around your car for a road map, perhaps you plan your travel route with an electronic device that uses global positioning satellite (GPS) technology or with computer software for mapping; you may obtain phone directions or rely on a driver for route planning. If you live in a city and travel by subway or bus, you may even have a complete tactile map of the transit system as a transportation resource. In unusual situations, you may have a portable version of the tactile map that you can consult for information while traveling. The distinctive role of maps for blind travelers is the subject of Practice Perspectives this month. Following this introduction are descriptions of two projects in which tactile maps were developed to address the needs of travelers who are blind. Before you read these pieces, however, consider how maps are used differently by people who are blind. In the absence of personal expertise on this topic, contacted four adults who are professionals in the field of visual impairment and blindness and are also blind. believed they could provide unique perspectives on map usage. They responded to my three questions with a rich variety of opinions and experiences. Eric Guillory, director of Youth Services at the Louisiana Center for the Blind in Ruston; Daniel Kish, founder and chief executive officer of World Access for the Blind in Huntington Beach, California, and an orientation and mobility instructor; Mark Nelson, chief operating officer for the Foundation for Blind Children in Phoenix, Arizona; and Sandy Ruconich, assistive technology specialist at the Utah Schools for the Deaf and the Blind and past president (2006-2008) of the Association for Education and Rehabilitation of the Blind and Visually Impaired, all spoke to me about their own experiences, which provide context for this Practice Perspectives feature. Their responses to my questions are described below, and their thoughtful comments are very much appreciated. DO YOU USE TACTILE MAPS AS AN ADULT? IF SO, HOW? Although Daniel, Eric, Mark, and Sandy all acknowledged that tactile maps were not often available to them as adults, they all had used them for specific purposes at some point in their lives. Mark uses tactile maps mainly for orientation at conferences and meetings as well as for consideration, with his administrative team, of the way space is used at the Foundation for Blind Children. Eric uses tactile maps mainly in his instructional role with children. He stated, I don't employ them when learning travel routes and/or the layouts of buildings. have already gained a good knowledge of cardinal directions and geographic relationships due to my previous exploration of tactile maps. Daniel reported that tactile maps are rarely available, recalling that he was disappointed on a visit to Disneyland to find that brailled information about the park was available for blind visitors, but the map provided to sighted visitors was not available in a tactile format. …