Most mass-produced apps and even signage meant for wayfinding provide only visual cues. Whether it be signage with street names or a map with directional arrows, they are seldom accessible to people with vision impairments. AccessMap Multimodal indicates landmarks such as waste bins, benches, APS signals, and other landmarks that are likely to be encountered along a pedestrian route by a cane user. Additionally, we organize information in a hierarchy for our step-by-step directions so that users may navigate more quickly among street names, landmarks, and other wayfinding information. Further, our step-by-step directions use descriptors like slight and sharp to distinguish different kinds of turns. While all of these features are useful, they would be less effective if the user had to actively get to each directional card and check the related information. Alerts on AccessMap also provide timely alerts through the user’s screen reader to indicate directions, tactile landmarks, street names, and even the buildings one is passing by as they traverse!

AccessMap consumes OpenSidewalks (OSW) data through a structured process that involves several key steps:

1) Data Extraction and Processing:
AccessMap has two primary sources for pedestrian data: the Transportation Data Equity Initiative system (TDEI) and OpenStreetMap (OSM). The TDEI system provides OpenSidewalks-formatted datasets, making data extraction as simple as unzipping a file. For data consumed from OSM, AccessMap extracts relevant data by downloading raw OSM files from the Geofabrik server and converting the data to the OpenSidewalks format. This may involve parsing the data to extract specific tags related to accessible pedestrian navigation (e.g., footways, sidewalks, street crossings, curb cuts, inclines, surface types).

2) Data Enrichment:
Additional attributes, such as incline, are derived from supplementary datasets to enhance the OpenSidewalks data. Street conflation is performed to link sidewalks with their corresponding streets, thereby improving navigation instructions. OpenSidewalks extensions, which represent adjacent features such as buildings and benches, are integrated into the pedestrian network, enabling more advanced navigation instructions and routing preferences.

3) Routing Graph Construction:
AccessMap constructs a routing graph from the enriched data. This graph represents the pedestrian network, with nodes (e.g., curbs) and edges (e.g., sidewalks). Each edge is annotated with attributes like length, incline, and surface type. Additionally, the outdoor pedestrian network represented by OpenSidewalks is connected to stations’ pathways represented by GTFS Pathways, facilitating a seamless transition between outdoor and indoor environments.

4) User Interface Integration:
Finally, the processed data is integrated into AccessMap’s user interface, allowing users to view and interact with the information through the map and navigation options.

If you are interested in adding your city to AccessMap, please email us at help@accessmap.atlassian.net. We will evaluate the eligibility of your city or region based on the completeness and quality of the pedestrian network data in OpenStreetMap and/or your local transportation agency data store.