In the framework of population ageing and increased importance attached to walking in urban cities, the aim of this PhD work is to better understand behavioral and biomechanical characteristics of older pedestrian road crossing. We mostly used the experimental method. Some data were collected in laboratory or natural environment, but the main study was performed in an immersive road crossing simulator with projected reality: the Simulator of Road for Pedestrians (SRP). The curb height was adjustable. The device integrated various biomechanical measurement tools such as force plates and 3D-gait analysis systems. The real and the imagined crossing times were compared in a task performed outside the simulator. It reveals that some seniors underestimated their crossing time. The experiment within the simulator confirmed the relevance of the age-related modulation of the crossing time perception, which was indirectly estimated by the feeling of endangerment. Inside the simulator, the road crossing behavior of the elderly participants was safe, requiring longer temporal intervals for deciding to initiate the crossing. In favorable traffic gap conditions, they walked more quickly than the younger participants and their safety margins were larger. The biomechanical approach revealed intergroup differences, some of which inducing potential risks (e.g., plantar flexion) while others (e.g., exploratory rotations) participated in the coping.
