Implementing auralized CPB sounds on a pedestrian simulator

Recently, several studies on pedestrian safety and particularly those addressing pedestrian crossing behaviour and decision-making have been performed using virtual reality systems. The use of simulators to assess pedestrian behaviour is conditioned by the feeling of presence and immersion, for which the sound is a determining factor. This paper presents an implementation procedure in which tyre-road noise samples are auralized and presented as auditory stimuli in a virtual environment, for assessing pedestrian crossing decision-making. The auditory samples obtained through the Close Proximity (CPX) method and subsequently auralized to represent Controlled Pass-By (CPB) recordings reproduce the sounds of a vehicle approaching a crosswalk. The auralized sounds together with the presentation of visual stimuli were used in an experiment carried out with 15 participants. Safety indicators, such as the time-to-passage at the moment that participants decided to cross a virtual crosswalk and the minimum time-to-collision were registered and compared with data obtained in real-world road crossings. The comparison of the results obtained in virtual and real environments, indicated a good suitability of the approach for studying pedestrian crossing behaviour.

A preliminary indication that the simulation approach used in the experiments is able to realistically depict road crossing situations, where the CPB auralized sounds certainly played an important role. However, full validation will require more in-depth studies of multiple conditions, to assess the suitability of the implementation of the approach as a valid tool for simulation-based safety analysis of car-pedestrian interactions. FCT – Fundação para a Ciência e a Tecnologia, under grant agreement [SFRH/BD/131638/2017] attributed to the first author; by FCT/MCTES through national funds (PIDDAC) under the R&D Unit Institute for Sustainability and Innovation in Engineering Structures (ISISE) [UIDB/04029/2020]; and by the project Promoting Scientific Production and Technological Development and Thematic Networking (3599-PPCDT), supported by the European Community Fund FEDER, through the grant attributed to the project AnPeB – Analysis of pedestrians behaviour based on simulated urban environments and its incorporation in risk modelling [PTDC/ECM-TRA/3568/2014]