Optimizing floor plans of accessible restrooms in elderly long-term care facilities: a path planning approach

Navigating narrow restrooms is challenging for the elderly using wheelchairs or walkers (EUWW). Existing research focuses on the convenience of furniture use in the restroom and overlooks the convenience of mobility between furniture pieces. However, the floor plans of accessible restrooms determine the mobility path of EUWW, affecting mobility convenience. Thus, to improve mobility, floor plans should be evaluated to shorten movement distances and reduce bends. Experiments in constructed environments were expensive. This study instead proposes a novel path-planning based method for accessible restroom floor plan evaluation, simulating mobility paths in a virtual environment, and evaluating how the floor plans of accessible restrooms affect mobility and convenience. The results showed that: (1) wheelchair users, who approach the toilet from the rear, and walker users find opposite wall toilet-sink arrangements convenient. While Wheelchair users, who approach the toilet from the side or front, find it convenient if the toilet and sink are situated on different walls at a 90° angle. Toilets and sinks on the same wall are inconvenient. (2) Corner sinks and toilets reduce EUWW's turning angles. (3) The farther the sink is from the side wall, the more convenient it is for EUWW. (4) The 45° side approach is the most convenient for moving, followed by the frontal approach, and lastly the 90° approach. Theoretically, this study uses path planning algorithms, simulating the movement of EUWW with varying capabilities and offering a new perspective for barrier-free architectural design. Practically, this study provides recommendations for optimizing accessible restroom floor plans.