Audio-visual perception of vehicles in traffic, phase 2

在第二阶段，我们的项目继续研究听觉感知和认知在安全移动中的作用，通过研究碰撞时间判断（TTC；“车辆何时会到达我的位置？”）从行人的角度来决定过马路。为此，我们使用了在第一阶段实施的电动和传统车辆在过马路场景中接近行人的交互式和逼真的视听虚拟现实模拟，我们将完善和扩展模拟系统。工作包（WP） A的目标是了解在第一阶段中一直观察到的内燃机加速车辆（ICE）的声音对TTC估计和过马路决策的有益影响的感知机制。WP B研究了距离、速度和加速度的听觉感知，用于接近车辆的具体情况。目的是解释在项目阶段1和WP A中观察到的基于基本任务的听觉敏感性的TTC估计和过马路决策中的线索权重，并以不同声音线索的可用性为条件。由于第一阶段的研究结果显示，即使配备了车辆声警报系统（AVAS），电动汽车加速时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设计，使其能够像内燃机汽车的声音一样有效地提供加速信息。沉浸式虚拟现实系统所描绘的交通状况和事件的真实性，在交通安全和声音质量调查中发挥着重要作用。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整体合理性有影响。在ttc估计和过马路决策实验中，研究复杂性对被试可信性评分和行为的影响。首先，在WP D中，考虑到车辆子声源的方向特性，增加了虚拟声源的复杂性。为此，提出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侧重于场景内容的复杂性，从空旷的街道到热闹的街道的复杂性，以及听觉模拟精度对可信性的影响。最后，WP F通过在交通安全实验中给受试者额外的智能手机任务或与人互动，调查了额外的技术和社会分心因素对受试者可信性评估和行为的影响。

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.