Fuzzy micro-scale accessibility indexes from the perception of pedestrians with disabilities: case study of a medium-sized Latin American city

Physical accessibility is an important characteristic of urban infrastructure, allowing safe, comfortable and independent pedestrian mobility. To assess such an aspect, it is convenient to consider how physical accessibility conditions are perceived by pedestrians, especially the most vulnerable ones, such as people with disabilities. Addressing this topic, the objective of this study was the development of accessibility indexes, called Fuzzy Sidewalk Accessibility Index − FSAI and Fuzzy Crosswalk Accessibility Index − FCAI, to evaluate the level of perceived accessibility by pedestrians with physical, visual and hearing disabilities, combining an evaluation checklist of micro-scale attributes and a questionnaire. Fuzzy logic and a multi-criteria assessment technique were applied to generate the proposed indexes, taking into account the subjectiveness and uncertainties that are inherent to the evaluation. Subsequently, the indexes were applied in a case study in a medium sized Brazilian city, to test their suitability in assessing the level of accessibility of sidewalks and crosswalks in the downtown area. Therefore, the present research innovates by addressing a context not frequently considered in this context — medium sized cities from Latin America — as well as by including the perception of pedestrians with different types of disabilities, while previous studies usually understand disabled individuals as an homogeneous group. In addition, the proposed accessibility indexes are the first to apply a fuzzy approach within the aforementioned context. The results from the case study indicated a general inadequacy of accessibility conditions, with no accessible pedestrian route identified in the area. It is clear that pedestrian intersections need careful attention in the city of Santa Maria, since all presented poor physical accessibility within the evaluated area. Installing adequate pedestrian signals and well painted and paved crosswalks should be a local priority. Furthermore, the FSAI and FCAI were demonstrated to be an adequate tool to measure physical accessibility in a detailed manner, addressing perceived accessibility by people with different disabilities, collaborating with a still lacking research area and innovating by including different types of disabilities and a micro-scale approach. Through the FSAI and FCAI application, stakeholders, city planners and researchers can classify pedestrian infrastructure on the level of accessibility, map accessible pedestrian routes and identify specific attributes that might represent priorities for improvement. Thus, the FSAI and FCAI allow to identify which micro-scale attributes of the sidewalks and crosswalks present the most concerning physical conditions within a given area, as well as which pedestrian routes need to be improved with more urgency, collaborating with urban planning focused on accessible pedestrian mobility.