Tactile Maps Research Articles

Effects of spatial learning using tactile maps on orientation accuracy by path integration and mental imagery walking in blindfolded sighted people

Purpose: Focusing on individuals with visual impairment, this study investigated the effects of spatial learning using tactile maps on orientation accuracy by path integration in physical and mental imagery walking scenarios. Materials and methods: Twelve blindfolded sighted people learned nonlooping routes with two corners using tactile maps composed of volumetric raised-line elements, then navigated the routes physically and mentally. At four orientation points along the route—the starting point, Corner A, Corner B, and the endpoint—participants indicated the direction of the other points by aligning a raised, tapered rectangle attached to a horizontal digital protractor. Results and Discussion: During the physical and mental walking tasks, the participants’ mean orientation error values, representing the error in angle from the correct orientation, approximated zero for all orientation directions. However, the mean absolute error, i.e. the absolute value of the orientation error, ranged from 12.5° to 32.5° across different orientation points and tasks. As the participants followed the route, the absolute error relative to the next direction of travel increased, and the absolute errors for orientation points they had passed were substantially large. These results indicate that although tactile maps do not always enable precise orientation, they provide navigators with a surveyed spatial understanding that assists orientation through path integration. Furthermore, the mean difference in orientation error between mental and walking tasks measured on the same route for all directions was not significantly different from zero. This suggests that mental imagery walking with the tactile map helps predict orientation performance by path integration in navigators without vision.

Tactile maps of historic gardens

Tactile maps of historic gardens

Tactile Simultaneous Localization and Mapping Using Low-Cost, Wearable LiDAR

Tactile maps are widely recognized as useful tools for mobility training and the rehabilitation of visually impaired individuals. However, current tactile maps lack real-time versatility and are limited because of high manufacturing and design costs. In this study, we introduce a device (i.e., ClaySight) that enhances the creation of automatic tactile map generation, as well as a model for wearable devices that use low-cost laser imaging, detection, and ranging (LiDAR,) used to improve the immediate spatial knowledge of visually impaired individuals. Our system uses LiDAR sensors to (1) produce affordable, low-latency tactile maps, (2) function as a day-to-day wayfinding aid, and (3) provide interactivity using a wearable device. The system comprises a dynamic mapping and scanning algorithm and an interactive handheld 3D-printed device that houses the hardware. Our algorithm accommodates user specifications to dynamically interact with objects in the surrounding area and create map models that can be represented with haptic feedback or alternative tactile systems. Using economical components and open-source software, the ClaySight system has significant potential to enhance independence and quality of life for the visually impaired.

Methodical testing of tactile cartographic signs in isolation and in context

ABSTRACT To date, the ways of testing tactile signs lack systematization. Hence, the aim of our research was to methodically evaluate the legibility of the proposed set of tactile signs. Our solution is based on the sign theory, in which signs have relations with reality, other signs, and users. We employed a two-step procedure by first assessing signs in isolation to verify the ease of decoding and differentiation of signs within the same geometry type, and then evaluating their correct interpretation in context – on a map with signs in different geometries. We validated our approach using signs designed for historic garden maps that formed our case study. We tested these signs across three matrices (for point, line and area signs). Most of the signs were correctly recognized by the study participants in the first attempt. Any illegible signs were redesigned and reevaluated in context using seven pseudomaps. At this stage, minor issues related to single signs arouse, primarily due to inappropriate pseudomap design rules rather than sign geometries themselves. Based on participants’ feedback, we refined the signs again, and finally obtained a standardized set of 52 legible signs, intended for 3D-printed tactile maps using the DLP technique. Our analysis confirms that the proposed signs are legible, regardless of the user’s skills and characteristics.

Inclusive Cities for Visually Impaired People

Objective: The objective of this study is to to present a literature review and its evolution regarding how elements of city architecture can contribute to the inclusion of the visually impaired and the most appropriate way to reproduce it, specifically in the context of Brazil. Theoretical Framework: The urban organization of a city can either contribute to or hinder human interactions, social inclusion, and the autonomy of people with disabilities. However, for a long time, cities were not planned to accommodate diversity, becoming even a segregating space for some minorities, such as the visually impaired. Method: The methodology adopted for this research includes the review and discussion of books, articles, specialized virtual pages, and pertinent legislation. Results and Discussion: The results obtained revealed that urban orientation elements for the visually impaired lack standardization, making them a hindrance to their perception. Research Implications: Future work needs to invest in the research for the standardization of tactile maps and floors, also incorporating new technologies. Originality/Value: This study contributes to the literature by discussing city architecture from the perspective of the visually impaired, highlighting practical contributions for better territorial performance for this specific population.

Enabling Self-Practice of Digital Audio–Tactile Maps for Visually Impaired People by Large Language Models

Digital audio–tactile maps (DATMs) on touchscreen devices provide valuable opportunities for people who are visually impaired (PVIs) to explore the spatial environment for engaging in travel activities. Existing solutions for DATMs usually require extensive training for the PVIs to understand the feedback mechanism. Due to the shortage of human resources for training specialists, as well as PVIs’ desire for frequent practice to maintain their usage skills, it has become challenging to widely adopt DATMs in real life. This paper discusses the use of large language models (LLMs) to provide a verbal evaluation of the PVIs’ perception, which is crucial for the independent practice of DATM usage. A smartphone-based prototype providing DATMs of simple floor plans was developed for a preliminary investigation. The evaluation results have proven that the interaction with the LLM could help the participants better understand the DATMs’ content and could vividly replicate them by drawings.

UV printed tactile maps of historic parks

UV printed tactile maps of historic parks

Solution-Processed Flexible Temperature Sensor Array for Highly Resolved Spatial Temperature and Tactile Mapping Using ESN-Based Data Interpolation.

High-performance flexible temperature sensors are crucial in various technological applications, such as monitoring environmental conditions and human healthcare. The ideal characteristics of these sensors for stable temperature monitoring include scalability, mechanical flexibility, and high sensitivity. Moreover, simplicity and low power consumption will be essential for temperature sensor arrays in future integrated systems. This study introduces a solution-based approach for creating a V2O5 nanowire network temperature sensor on a flexible film. Through optimization of the fabrication conditions, the sensor exhibits remarkable performance, sustaining long-term stability (>110 h) with minimal hysteresis and excellent sensitivity (∼-1.5%/°C). In addition, this study employs machine learning techniques for data interpolation among sensors, thereby enhancing the spatial resolution of temperature measurements and adding tactile mapping without increasing the sensor count. Introducing this methodology results in an improved understanding of temperature variations, advancing the capabilities of flexible-sensor arrays for various applications.

Evaluation of Qualitative Colour Palettes for Tactile Maps

Much attention is currently being paid to developing universally designed solutions. Tactile maps, designed for people with visual impairments (PVI), require both graphic and tactile content. While many more- or less-official guidelines regarding tactile symbols exist, the subject literature lacks clear guidance on creating legible, highly contrasting graphic symbols for visual perception by those with residual vision. This study specifically addresses the application of colour, a key graphic variable that Is most often used to differentiate area symbols. We wanted to verify whether it is possible to choose a universal qualitative colour palette for tactile maps. We have proposed four different palettes, each with eight colours, that were later evaluated in a controlled study by 16 PVI with varying sociodemographic characteristics, using the VIEW model. The model is widely applied in the area of marketing research and considers the following aspects: Visibility, Informational, Emotional Appeal, and Workability. Our results indicate a lack of unanimity in choosing the best qualitative palette. The results of three palettes are comparable, with a subtle preference for the palette optimized for colour differences using the Python algorithm. Notably, the palette commonly used in official tactile maps in Poland received the lowest scores in every analysed dimension.

Haptic search asymmetry does not occur due to different-shaped tactile symbols on capsule paper.

Previous research on haptic search using sandpaper with different roughness levels as a target and distractors showed that rough sandpaper among fine "pops out" and can be searched for in a shorter time than when the roles of the target and distractors are reversed. However, it is not clear whether the same search asymmetry occurs with differences in the shapes of tactile symbols on capsule paper. To explore this possibility, we conducted a haptic search experiment using circles with or without a dot on capsule paper as a target and distractors, which are often used as point symbols in tactile maps for the blind. Contrary to our expectations, haptic search asymmetry did not occur between these two tactile symbols. Regardless of target type, the search times increased in proportion to the number of items (distractors plus target), as participants tended to adopt serial search strategy in which they placed their index or middle finger on the tactile symbol to distinguish it every time they found a new one. The ratio of the search times for target-absent to target-present trials is precise alignment with the occurrence rate of repetitive search trials.

Producing accessible intersection maps for people with visual impairments: an initial evaluation of a semi-automated approach

ABSTRACT Street intersections are challenging for people with visual impairments. While tactile maps are an important support in both mobility training and independent journeys, the caseload of manual map production has made them less accessible. This paper explores the possibility of (semi-) automatically producing tactile maps for street intersections at large scales, with an initial evaluation focused on the graphic aspect of the produced maps. The automation attempts to identify acceptable default parameters and values and proposes an exploration of possible choices for potentially open decisions. It adapts the classic map production process with parameters to present the information tactilely at the intersection scale, and produces representation meaningful for PVIs and realistic for an automatic procedure, resulting in ready-to-print maps in two scales of three sizes, with different levels of details and styles. The resulting maps are evaluated by professionals involved in tactile graphics through a questionnaire to evaluate the defaults and discuss the possibility of open choices. The professionals validated the maps, and their evaluation emphasized the need to have an acceptable default while keeping some options open to cater to the diversity in the visually impaired audience.

Fully Digital Audio Haptic Maps for Individuals with Blindness

Tactile maps designed for individuals with blindness can greatly improve their mobility, safety and access to new locations. While 3D-printed maps have already been demonstrated to be a powerful tool for delivering spatial information, they might not always be available. Alternatively, a combination of audio and haptic information can be used to efficiently encode 2D maps. In this paper, we discuss the development and user-testing of a novel audio-haptic map creator application. Maps created using this application can provide people with blindness with a tool for understanding the navigational routes and layouts of spaces before physically visiting the site. Thirteen people with blindness tested various components of the virtual map application, such as audio, haptic feedback and navigation controls. Participants’ data and feedback were collected and analyzed to determine the effectiveness of the virtual maps as it relates to this user group’s readability and usability. The study showed that it was easy to use and that it efficiently delivered information about travel routes and landmarks that the participants could successfully understand.

Community-based, inclusive design of a 3D tactile map to enable playground navigation for children who are visually impaired and blind.

The LSU Community Playground Project (LSUCPP) collaborates with communities (especially the true experts at play, the children) to design and build playgrounds that reflect "the soul of the community." One member of the LSUCPP undertook a research project in an effort to design better playgrounds for use by children who are visually impaired or blind. A recommendation from this research was to provide a 3D-printed tactile map of each play area, such that children who were visually impaired or blind could feel the location and type of equipment and ground surfaces prior to entering a playground, which would enable them to play independently. In this paper, we tell the story of how engineering students and faculty collaborated with children with visual impairments or blindness and their teachers and professional staff to co-design and build a 3D printed tactile map at the Louisiana School for the Visually Impaired (LSVI). Specifically, we detail how we co-designed this artifact, the ways in which the artifact developed due to this inclusive approach, briefly present the design, and discuss how engineers engaged in the design of assistive technologies can put inclusive design principles and community-based design processes into action.

Adults' spatial scaling of tactile maps: Insights from studying sighted, early and late blind individuals.

The current study investigated spatial scaling of tactile maps among blind adults and blindfolded sighted controls. We were specifically interested in identifying spatial scaling strategies as well as effects of different scaling directions (up versus down) on participants' performance. To this aim, we asked late blind participants (with visual memory, Experiment 1) and early blind participants (without visual memory, Experiment 2) as well as sighted blindfolded controls to encode a map including a target and to place a response disc at the same spot on an empty, constant-sized referent space. Maps had five different sizes resulting in five scaling factors (1:3, 1:2, 1:1, 2:1, 3:1), allowing to investigate different scaling directions (up and down) in a single, comprehensive design. Accuracy and speed of learning about the target location as well as responding served as dependent variables. We hypothesized that participants who can use visual mental representations (i.e., late blind and blindfolded sighted participants) may adopt mental transformation scaling strategies. However, our results did not support this hypothesis. At the same time, we predicted the usage of relative distance scaling strategies in early blind participants, which was supported by our findings. Moreover, our results suggested that tactile maps can be scaled as accurately and even faster by blind participants than by sighted participants. Furthermore, irrespective of the visual status, participants of each visual status group gravitated their responses towards the center of the space. Overall, it seems that a lack of visual imagery does not impair early blind adults' spatial scaling ability but causes them to use a different strategy than sighted and late blind individuals.

Accessible Point-and-Tap Interaction for Acquiring Detailed Information about Tactile Graphics and 3D Models.

We have devised a novel "Point-and-Tap" interface that enables people who are blind or visually impaired (BVI) to easily acquire multiple levels of information about tactile graphics and 3D models. The interface uses an iPhone's depth and color cameras to track the user's hands while they interact with a model. When the user points to a feature of interest on the model with their index finger, the system reads aloud basic information about that feature. For additional information, the user lifts their index finger and taps the feature again. This process can be repeated multiple times to access additional levels of information. For instance, tapping once on a region in a tactile map could trigger the name of the region, with subsequent taps eliciting the population, area, climate, etc. No audio labels are triggered unless the user makes a pointing gesture, which allows the user to explore the model freely with one or both hands. Multiple taps can be used to skip through information levels quickly, with each tap interrupting the current utterance. This allows users to reach the desired level of information more quickly than listening to all levels in sequence. Experiments with six BVI participants demonstrate that the approach is practical, easy to learn and effective.

Establishing Natural Tactile Mappings: Mapping Tactile Parameters to Continuous Data Concepts.

There has been limited work developing natural mappings between tactile signals and common data concepts in data rich domains. If these mappings can be established, tactile displays can become more intuitive and readily adopted. The present study aims to identify general natural mappings between perceptual dimensions of vibration and continuous data concepts. Twenty-one participants were tasked to map four different tactile parameters to four different data concepts-pressure, concentration, size, and speed. We found that an increase in intensity was good at conveying increases for all data concepts. We also found that speed, pressure, concentration, and size all have at least one strong natural mapping.

Blind people can actively manipulate virtual objects with a novel tactile device

Frequently in rehabilitation, visually impaired persons are passive agents of exercises with fixed environmental constraints. In fact, a printed tactile map, i.e. a particular picture with a specific spatial arrangement, can usually not be edited. Interaction with map content, instead, facilitates the learning of spatial skills because it exploits mental imagery, manipulation and strategic planning simultaneously. However, it has rarely been applied to maps, mainly because of technological limitations. This study aims to understand if visually impaired people can autonomously build objects that are completely virtual. Specifically, we investigated if a group of twelve blind persons, with a wide age range, could exploit mental imagery to interact with virtual content and actively manipulate it by means of a haptic device. The device is mouse-shaped and designed to jointly perceive, with one finger only, local tactile height and inclination cues of arbitrary scalar fields. Spatial information can be mentally constructed by integrating local tactile cues, given by the device, with global proprioceptive cues, given by hand and arm motion. The experiment consisted of a bi-manual task, in which one hand explored some basic virtual objects and the other hand acted on a keyboard to change the position of one object in real-time. The goal was to merge basic objects into more complex objects, like a puzzle. The experiment spanned different resolutions of the tactile information. We measured task accuracy, efficiency, usability and execution time. The average accuracy in solving the puzzle was 90.5%. Importantly, accuracy was linearly predicted by efficiency, measured as the number of moves needed to solve the task. Subjective parameters linked to usability and spatial resolutions did not predict accuracy; gender modulated the execution time, with men being faster than women. Overall, we show that building purely virtual tactile objects is possible in absence of vision and that the process is measurable and achievable in partial autonomy. Introducing virtual tactile graphics in rehabilitation protocols could facilitate the stimulation of mental imagery, a basic element for the ability to orient in space. The behavioural variable introduced in the current study can be calculated after each trial and therefore could be used to automatically measure and tailor protocols to specific user needs. In perspective, our experimental setup can inspire remote rehabilitation scenarios for visually impaired people.

부산 공공문화시설의 유니버설디자인 적용

The purpose of this study is to analyze the status of universal design application at the Busan Cultural Center and suggest improvement measures. The facilities of the Busan Cultural Center were divided into six areas and a checklist of application evaluation elements of universal design was formed and an on-site investigation was conducted. As a result of the analysis, first, in the case of intermediate facilities, it is necessary to improve and manage the floor finish and gaps of access roads, and to provide safety passageways for pedestrians. Second, in the case of interior and exterior facilities, swing doors need to be replaced with automatic sliding doors, and more information signs and guidance blocks must be installed. Third, in the case of sanitary facilities, there must be sufficient facilities that can be used by users of various age groups, such as diaper changing tables and children's toilets, and a nursing room must be provided. Fourth, in the case of information facilities, it is necessary to install tactile maps and brochures written in Braille, and it is necessary to prepare a separate low-height information desk. This study can be used as basic data for applying universal design to public cultural facilities in Busan to create an environment where anyone can enjoy culture and arts.

Thematic tactile maps for accessible flood mitigation planning: design and evaluation

ABSTRACT Maps are frequently employed in the natural hazard mitigation planning (NHMP) process for analyze a community’s vulnerability to hazards and illustrating the character of potential hazards. But because the encoded information of these maps relies on visual access, blind or low-vision (B/LV) people who want to contribute to their community’s NHMP efforts are therefore effectively excluded from any stage of the process involving maps. In response, we investigate tactile flood maps as an accessible tool for NHMP. Our study proposes a workflow for creating thematic tactile flood maps using existing resources, methods, and design conventions, and then evaluates those thematic tactile maps to understand user confidence amongst B/LV users. This work contributes a proposed configuration of tactile mapping resources to be used for NHMP and evaluates user confidence while using those resources. Results suggest that B/LV users respond positively to using tactile maps in a high-stakes context such as NHMP, and that tactile maps can expand the number and diversity of people who are able to contribute to NHMP. To maximize contributions, we recommend that future tactile map research invest a greater amount of attention to developing resources for B/LV people to create, edit, and distribute maps themselves.

Tactile perception of randomness: Effect of varying stimulus size and participants age.

We investigated participants' ability to differentiate between random and organized two-dimensional tactile tiles with embossed dots and examined how this ability varies with size and participant age. Four experiments were conducted to evaluate the effect of these variations on participants' capacity to utilize touch in identifying which of two stimuli exhibited greater randomness. Participants were instructed to explore embossed tiles using both hands. The tiles had varying levels of randomness from organized to random sets. In Experiments 1, 2, and 4, the sets were of equal size, while in Experiment 3, they differed in size. Results revealed a significant difference between the random and organized sets, with random stimuli being more easily discernible. These findings suggest that touch can be utilized to discern random patterns on tactile maps or displays. However, older participants encountered difficulties making this distinction, indicating similarities between vision and touch in perceiving randomness.