# Indoor-Guided Navigation for People Who Are Blind: Crowdsourcing for Route Mapping and Assistance
## 5 Web-Crowd-Assisted Social Networking Implications for Navigation Indoors
The latter is needed when there is no internet connection. In navigational mode, the BSVI user's wearable ETA system generates a video and sensory data stream, which are provided to the web cloud database and machine learning algorithms for analysis. In this way, objects, location IDs, scenes, and sensory data recognition occur almost in real-time to give navigational support to the BSVI user. When a BSVI user becomes lost or disoriented, the system can work using a dead reckoning method, i.e., guide the user to the last known location ID place (see Figures 16 and 17). For that matter, the system continually tracks movement using accelerometer, magnetometer, gyroscope, and compass information. This allows for the route of a person who is BSVI to be traced back to the last known location ID. Disorientation cases can be recorded, depersonalized, and processed to warn prospective BSVI users and improve the route guiding quality. While navigating indoors with the ETA guiding system, BSVI users can approve and make estimates and additions to the route's DB navigation and orientation information (for instance, they can mark new objects, provide voice comments, make new location IDs, etc.). This information is used for improvements to and validation, credibility, and rating of routes. Similarly, BSVI users can add comments about the route regarding observed difficulties, inaccuracies, and errors. Wayfinding and indoor navigation services for the BSVI population generally have to perform one or more of the following functions: familiarization, localization, route planning, and communication with the user in a meaningful manner through an accessible interface. The specific abovementioned web-crowd interface advantages only work well in the context of the whole ETA system (see Figure 17). Figure 16: BSVI interface with the ETA system’s web cloud database while choosing route and navigating indoors. Consequently, all three modalities are used where:  
1. Proposed visual odometry and SLAM (simultaneous localization and mapping) methods used for sequential recognition of route views have a competitive edge (comparing with other technologies) as they use modern advancements of deep neural networks (such as the convolutional NN);
2. The proposed navigation and orientation method works as an augmented reality decision support system that enables a better perception of indoor environments and does not interfere with the natural senses of the user;
3. It eliminates the need for infrastructural installations such as special marks on the floors, WiFi signal triangulation, 5G signals, beacons, installed Bluetooth devices, RFID, etc. ;
4. People who are BSVI can take an active part not only in the rating of passed routes but also in creating and improving them with the help of the ETA system and dedicated software subsystem. The integration of third-party geospatial indoor information gives additional information needed for matchmaking with the visual SLAM information. However, the proposed innovative experience-centric methods and interfaces present some challenges:  
1. Developing routes that can reflect the exact needs and preferences of each individual and their disabilities, given the range of disability conditions and individual preferences;
2. Capturing and adequately quantifying all sensory parameters that affect wayfinding choices and navigation preferences;
3. Building accurate web cloud databases in a scalable and affordable manner;  
Figure 17: The functionality of the second and third modalities using volunteers’ assistance. 4. Updating the route database with frequent changes (such as construction) in a scalable and affordable manner;
5. Mapping indoor spaces in affordable and scalable ways while preserving the privacy of relevant information as needed. However, these challenges can be mitigated by adopting an experience-centric approach, where communication and collaboration among members of social navigation networks and other trusted sources form the basis of providing wayfinding assistance.