Automatic Generation of High-Accuracy Stair Paths for Straight, Spiral, and Winder Stairs Using IFC-Based Models

Abstract

The indoor space model is the foundation of most indoor location-based services (LBS). A complete indoor space model includes floor-level paths and non-level paths. The latter includes passages connecting different floors or elevations such as stairs, elevators, escalators, and ramps. Most related studies have merely discussed the modeling and generation of floor-level paths, while those considering non-level paths usually simplify the formation and generation of non-level paths, especially stairs, which play an important role in emergency evacuation and response. Although the algorithm proposed by i-GIT approach, which considers both floor-level and non-level paths, can automatically generate paths of straight stairs, it is not applicable to the spiral stairs and winder stairs that are common in town houses and other public buildings. This study proposes a novel approach to generate high-accuracy stair paths that can support straight, spiral, and winder stairs. To implement and verify the proposed algorithm, 54 straight and spiral stairs provided by Autodesk Revit’s official website and three self-built winder stairs are used as test cases. The test results show that the algorithm can successfully produce the stair paths of most test cases (49/50), which comprehensively extends the applicability of the proposed algorithm.

Automatic Generation of 3D Indoor Navigation Networks from Building Information Modeling Data Using Image Thinning

“…It bridges any two nodes with a visible edge, if the edge does not intersect with any object. Visibility graphs can be applied to facilitate some indoor LBS [20,24]. It has two disadvantages: The first challenge is related to the way humans perceive paths [9,30].…”

“…It has two disadvantages: The first challenge is related to the way humans perceive paths [9,30]. The second challenge concerns the exponential growth in the number of edges as the number of visible nodes increases [9,20].…”

“…A comprehensive 3D indoor map ought to encompass both floor-level and cross-floor paths. Although many studies point out that cross-floor paths are primary components of 3D indoor maps, only a few efforts [9,20] have been made to achieve the auto-generation of cross-floor indoor maps.…”

“…(2) Cross-floor path generation. While previous studies [9,20] have explored generating cross-floor paths from BIM data, these methods may not be easily adaptable to irregular architectural components, e.g., winding stairs and curved ramps. As a result, automatically generating navigation paths from such irregular architectural components remains a challenging task.…”

Extracting 3D Indoor Maps with Any Shape Accurately Using Building Information Modeling Data

“…They mainly focus on finding the shortest, collision-free path within a single-story space based on the IFC model, without clearly introducing how to process the cross-floor elements. Lin et al [37] proposed a novel approach to generate high-accuracy stair paths that can support straight, spiral, and winder stairs. To verify the proposed algorithm, they used 54 straight and spiral stairs provided by Autodesk Revit's official website and three self-built winder stairs as test cases.…”