fNIRS dataset for the driving risk cognition of passengers in highly automated driving scenarios

A total of 20 participants completed this driving simulator experiment. This study complied with the Declaration of Helsinki and was approved by the Institutional Review Board of Tsinghua University, China. Participants were voluntary after the task and informed consent had been explained, and they also were informed that they may terminate this experiment at any time without any type of penalty. This experiment need participants focus on the front scenarios, so few random stimulating sounds are added in each VTD segment. When doing experiment, participant sits in this driving simulator and looks at the front screen. When he feels dangerous or hears a stimulating sound, he is asked to press the keyboard. This dataset is collected using a human factor signal acquisition system, and it includes a driving simulator, a hardware-in-loop equipment, and a host computer. This hardware-in-loop equipment is a Redhawk system, which is a real-time system, and runs Virtual Test Drive (VTD) software; The host computer is a window system and runs Matlab/Simulink, Python module and Oxysoft software. The functions of Matlab/Simulink include the communication between hardware-in-loop equipment and host computer by using User Datagram Protocol (UDP) and the communication between host computer and Oxysoft software; Python module will record the time when they press a keyboard; Oxysoft software and blood oxygen monitoring device work together for acquiring cerebral oxy-haemoglobin change ΔHbO and deoxy-haemoglobin change ΔHbR of passengers. When Matlab/Simulink receives the data about position, velocity and acceleration of ego vehicle and target vehicle (or pedestrian), the raw data of ΔHbO and ΔHbR and participant status, and Matlab/Simulink will joint those data with current time, then compose a new data. When all participants finish this experiment, the new data in same highly automated driving scenario is extracted based on time, and those data is considered as a group. The data of each participant in a highly automated driving scenario is considered as a sample data, and the sample data contains the information of position, velocity acceleration about ego vehicle and target vehicle (or pedestrian) and the raw data of ΔHbO and ΔHbR. Besides, the sample data also contains a kinetic energy field and a flag bit, the kinetic energy field may indicate a danger degree of driving scenario, and it involves relative longitudinal distance and the speed of target vehicle (or pedestrian); The flag bit indicates that whether or not the period in a sample time contains a stimulating sound, if it is true, then the period contains a stimulating sound, or not.

本驾驶模拟器实验共有20名参与者完成。本研究符合《赫尔辛基宣言》，并获得中国清华大学机构审查委员会的批准。参与者均为自愿参与，实验前已向其说明任务内容与知情同意事项，同时告知其可随时终止实验且不会受到任何处罚。由于本实验要求参与者专注于前方路况，因此在每个Virtual Test Drive（VTD）片段中会加入少量随机刺激性音效。实验过程中，参与者坐在驾驶模拟器内，注视前方屏幕；当感知到危险或听到刺激性音效时，需按下键盘作出反应。本数据集通过人机工程信号采集系统完成采集，该系统包含驾驶模拟器、半实物仿真设备以及上位机。其中半实物仿真设备为Redhawk系统，属于实时系统，运行Virtual Test Drive（VTD）软件；上位机为Windows系统，运行Matlab/Simulink、Python模块以及Oxysoft软件。Matlab/Simulink的功能包括：通过用户数据报协议（User Datagram Protocol, UDP）实现半实物仿真设备与上位机的通信，以及上位机与Oxysoft软件的通信；Python模块用于记录参与者按下键盘的时刻；Oxysoft软件与血氧监测设备协同工作，以采集受试者的脑血氧合血红蛋白变化量ΔHbO与脱氧血红蛋白变化量ΔHbR。当Matlab/Simulink接收到自车与目标车辆（或行人）的位置、速度、加速度数据，ΔHbO、ΔHbR的原始数据以及参与者状态信息后，会将这些数据与当前时刻进行关联整合，生成新的复合数据。待所有参与者完成实验后，基于时间从同一高度自动化驾驶场景的新数据集中提取数据，并将此类数据划分为一个数据组。每位参与者在单个高度自动化驾驶场景下的数据被视为一条样本数据，样本数据包含自车与目标车辆（或行人）的位置、速度、加速度信息，以及ΔHbO、ΔHbR的原始数据。此外，样本数据还包含动能场与标记位：动能场可用于表征驾驶场景的危险程度，其涉及目标车辆（或行人）的相对纵向距离与行驶速度；标记位用于标识样本时间段内是否存在刺激性音效，若标记为真，则表示该时间段包含刺激性音效，反之则无。