Audio-visual perception of vehicles in traffic, phase 2

在AUDICTIVE的第二阶段，我们的项目继续研究听觉感知和认知对安全移动的作用，通过研究碰撞时间的判断(TTC；车辆什么时候到达我的位置？)以及从行人的角度做出过街决定。为此，我们使用了第一阶段实现的电动和传统车辆接近行人的交互式、逼真的视听虚拟现实模拟，并将对模拟系统进行完善和扩展。工作包(WP)A的目标是了解内燃机(ICE)车辆加速的声音对TTC估计和道路穿越决策的有益影响的感知机制，这些影响在阶段1中一直被观察到。工作包B针对接近的车辆的特定情况，研究对距离、速度和加速度的听觉感知。其目的是解释TTC估计中的线索权重，以及在项目第一阶段和WP A中观察到的基于基本任务中的听觉敏感度的线索权重，并以不同的声学线索的可用性为条件。由于第一阶段的结果显示，即使安装了车辆声学报警系统(AVAS)，电动汽车加速的声音带来的好处也要小得多，因此WP C研究了如何改进AVAS的设计，以便它们能够像ICE车辆的声音一样有效地提供加速信息。在身临其境的虚拟现实系统中描绘的交通情况和事件的真实性，可以在交通安全和音质调查中发挥重要作用。设计方面和虚拟现实环境的复杂性对这些基于虚拟现实的模拟的总体真实性有影响。复杂性对受试者的可信等级和行为的影响将在TTC估计和过马路决策的实验中进行调查。首先，在WP D中，通过考虑车辆子源的方向特性来增加虚拟声源的复杂性。为此，开发了一种新的车辆记录方法，并在此基础上建立了新的虚拟源模型。WP E关注场景内容的复杂性，从空荡荡的街道到热闹街道的复杂性，以及听觉模拟准确性对似真度的影响。最后，WP F通过在交通安全实验期间给受试者额外的智能手机任务或与人互动来调查额外的技术和社会分心因素对受试者可信评估和行为的影响。

In the second phase of AUDICTIVE, our project continues to investigate the role of auditory perception and cognition for safe mobility, by studying judgments of time-to-collision (TTC; "When will the vehicle arrive at my position?") and street-crossing decisions from a pedestrian's perspective. For this, we use the interactive and realistic audio-visual virtual-reality simulations of electric and conventional vehicles approaching pedestrians in a street-crossing scenario that were implemented in the first phase, and we will refine and extend the simulations systems. The objective of work package (WP) A is to understand the perceptual mechanisms underlying the beneficial effects of the sound of accelerating vehicles with internal combustion engine (ICE) on TTC estimation and street-crossing decisions that were consistently observed in phase 1. WP B investigates the auditory perception of distance, velocity, and acceleration, for the specific case of approaching vehicles. The aim is to explain the cue weights in TTC estimation and street-crossing decisions observed in project phase 1 and in WP A based on the auditory sensitivity in the basic tasks, and conditional on the availability of different acoustic cues. Because the results of phase 1 showed a significantly smaller benefit of the sound of accelerating electric vehicles, even with acoustic vehicle alerting system (AVAS), WP C investigates how AVAS designs can be improved so that they provide acceleration information as effectively as the sound of an ICE vehicle. Plausibility of the traffic situations and events, which are portrayed within an immersive virtual reality system, can play an important role on the traffic safety and sound quality investigations. Design aspects and the complexity of the VR environment have an influence on the perceived overall plausibility of these virtual-reality-based simulations. The effect of complexity on plausibility ratings and behavior of subjects will be investigated in experiments on TTC-estimation and street-crossing decisions. First, in WP D, the complexity of virtual sound sources is increased by taking into account the directional characteristics of vehicle sub-sources. For this purpose, a new vehicle recording method is developed, based on which new virtual source models are created. WP E focuses on the complexity of scene content, from an empty street to the complexity of a lively street, and the influence of auditory simulation accuracy on plausibility. Finally, WP F investigates the influence of additional technical and social distraction factors on the plausibility evaluation and behavior of the subjects by giving them additional tasks with smartphones or interactions with people during traffic safety experiments.