This paper presents a novel, wearable navigation system for visually impaired and blind pedestrians that combines a global positioning system (GPS) for user outdoor localization and tactile-foot stimulation for information presentation. Real-time GPS data provided by a smartphone are processed by dedicated navigation software to determine the directions to a destination. Navigational directions are then encoded as vibrations and conveyed to the user via a tactile display that inserts into the shoe. The experimental results showed that users were capable of recognizing with high accuracy the tactile feedback provided to their feet. The preliminary tests conducted in outdoor locations involved two blind users who were guided along 380–420 m predetermined pathways, while sharing the space with other pedestrians and facing typical urban obstacles. The subjects successfully reached the target destinations. The results suggest that the proposed system enhances independent, safe navigation of blind pedestrians and show the potential of tactile-foot stimulation in assistive devices.

This paper proposes a novel framework for a better understanding of human cognitive locomotion and its interaction with the new tactile technologies that assist mobility and the acquisition of spatial knowledge in the absence of sight [case of visually impaired people (VIP), seniors, etc.]. Unlike the existing mobility models, the proposed framework encompasses four elements: 1) walking with obstacle avoidance, 2) orientation, 3) spatial awareness, and 4) actual physical displacement, and is based on the concept of the tactile gist, a refreshable (dynamic) egocentric tactile representation of the perceived scene. The relevance of the tactile gist concept for achieving the assistance of human mobility has been evaluated with three basic original spatial experiments (homing with obstacle avoidance, localization of a passage and its size estimation, and navigation in an apartment) using a purposely designed perception-movement platform and a touch stimulating tangible wearable refreshable device. The collected results show that the tactile gist might be considered as a scene representation and should be integrated into an assistive device for sightless people. The proposed approach may impact the design of mobility aids for VIP as it reinforces their natural mobility skills and may lead to new mobility strategies of VIP in (un-)known environment.

Today's technology still limits the accessing to 2D information (images, graphics, charts, maps, paintings, etc.) for visually impaired people (VIP). Existing solutions for human-machine interfaces are expensive and have yet to be available to the many. Therefore, we propose a novel and inclusive haptic architecture to access and interact with 2D data, relying on the force-feedback principle, and named Force-Feedback Tablet (F2T). The F2T's architecture is based on a flat thumbstick mounted on a 2D actuated support, enabling force feedback effects on user's finger. The flat thumbstick measures the user's intended movements independently from mobile support's actual movements, enabling highly interactive effects, static and dynamic effects, or guidances. Moreover, the mechanical structure does not need to be backdrivable, simplifying the motion control, and reducing the costs of the device. Finally, the F2T architecture allows designing lightweight, compact and scalable devices. To validate and demonstrate the relevance of the F2T architecture, we present two lightweight prototypes. Two series of preliminary tests with VIP and blindfolded participants confirmed the system's effectiveness at providing shape and spatial layout understanding. Results obtained during the evaluation are encouraging with high recognition rates.

This paper presents a novel bio-inspired predictive model of visual navigation inspired by mammalian navigation. This model takes inspiration from specific types of neurons observed in the brain, namely place cells, grid cells and head direction cells. In the proposed model, place cells are structures that store and connect local representations of the explored environment, grid and head direction cells make predictions based on these representations to define the position of the agent in a place cell’s reference frame. This specific use of navigation cells has three advantages: First, the environment representations are stored by place cells and require only a few spatialized descriptors or elements, making this model suitable for the integration of large-scale environments (indoor and outdoor). Second, the grid cell modules act as an efficient visual and absolute odometry system. Finally, the model provides sequential spatial tracking that can integrate and track an agent in redundant environments or environments with very few or no distinctive cues, while being very robust to environmental changes. This paper focuses on the architecture formalization and the main elements and properties of this model. The model has been successfully validated on basic functions: mapping, guidance, homing, and finding shortcuts. The precision of the estimated position of the agent and the robustness to environmental changes during navigation were shown to be satisfactory. The proposed predictive model is intended to be used on autonomous platforms, but also to assist visually impaired people in their mobility.