Motion-capture-based walking simulation of digital human adapted to laser-scanned 3D as-is environments for accessibility evaluation

Abstract

Owing to our rapidly aging society, accessibility evaluation to enhance the ease and safety of access to indoor and outdoor environments for the elderly and disabled is increasing in importance. Accessibility must be assessed not only from the general standard aspect but also in terms of physical and cognitive friendliness for users of different ages, genders, and abilities. Meanwhile, human behavior simulation has been progressing in the areas of crowd behavior analysis and emergency evacuation planning. However, in human behavior simulation, environment models represent only “as-planned” situations. In addition, a pedestrian model cannot generate the detailed articulated movements of various people of different ages and genders in the simulation. Therefore, the final goal of this research was to develop a virtual accessibility evaluation by combining realistic human behavior simulation using a digital human model (DHM) with “as-is” environment models. To achieve this goal, we developed an algorithm for generating human-like DHM walking motions, adapting its strides, turning angles, and footprints to laser-scanned 3D as-is environments including slopes and stairs. The DHM motion was generated based only on a motion-capture (MoCap) data for flat walking. Our implementation constructed as-is 3D environment models from laser-scanned point clouds of real environments and enabled a DHM to walk autonomously in various environment models. The difference in joint angles between the DHM and MoCap data was evaluated. Demonstrations of our environment modeling and walking simulation in indoor and outdoor environments including corridors, slopes, and stairs are illustrated in this study. Highlights An adaptive walking simulation algorithm of the digital human was developed. The environment models are automatically generated from laser-scanned point clouds. A digital human can walk autonomously in various as-built environment models. Simulated walking motion of the digital human is similar to one of real human. Elapsed time of modeling and simulation is short enough for practical application.

Simulation-Based Evaluation of Ease of Wayfinding Using Digital Human and As-Is Environment Models

“…A schematic of the proposed system is shown in Figure 1. To achieve this goal, we draw on the results of our previous studies, in which algorithms of as-is environment modeling [22], walking simulation of a digital human model (DHM) in that environment model [23], and basic wayfinding simulation of the DHM [24] were developed.…”

“…G I can be created automatically using SfM with a set of photographs of the environment [24]. Detailed algorithms and demonstrations are given in our previous studies [22][23][24]. 4.…”

“…This optimization algorithm is designed to make V T more natural and smooth, while avoiding contact with walls. The details are described in [23]. , where ∈ is a passing point representing a walking route indicated by of , .…”

“…, where ∈ is a passing point representing a walking route indicated by of , . After determining , the walking trajectory = 〈 〉 is generated automatically by our previously developed optimization algorithm [23], where represents a sequence of sparsely discretized target pelvis positions of the DHM. This optimization algorithm is designed to make more natural and smooth, while avoiding contact with walls.…”

“…Finally, the walking motion of the DHM is generated as it follows V T using our MoCap-based adaptive walking motion generation algorithm [23]. In the algorithm, realistic articulated walking movements of the DHM are generated based on MoCap data M for flat walking.…”