风险情境下老年驾驶人行为特性研究

为研究风险情境下老年驾驶人与中青年驾驶人行为特性的差异，并确定老年驾驶人的眼动、心理生理、驾驶操作及风险感知等各类行为特性的衰退情况；选取19位老年驾驶人和19位中青年驾驶人作为试验对象，应用眼动仪、生理仪及驾驶模拟平台开展驾驶模拟试验；采集5种风险场景下2组驾驶人的眼动、心理、生理、操作行为与车辆运行数据；对比分析2组驾驶人的注视及扫视等眼动行为特性、心率变异及皮电等心理生理行为特性、制动及转向等操作行为特性、风险反应及敏感度等风险感知行为特性。试验结果表明：2组驾驶人的各类行为特性均随风险等级的增加呈现一定的规律性变化，随着风险等级的增加，2组驾驶人的注视持续时间、皮电均值及增长率、心率增长率和风险敏感度亦随之增加，而扫视、心率变异指标SDNN、制动时间及风险反应时间等指标随风险等级的增加而下降；上述指标的规律性变化说明驾驶人对风险的关注度和敏感度随着风险自身危险性的上升而不断增加，进而做出的反应也就越早，同时伴随着心理紧张程度增加，需要付出的努力也越大，与年龄的高低无关；另一方面，老年驾驶人的各类行为特性出现明显的衰退且与中青年驾驶人存在显著差异，其中老年驾驶人的注视持续时间、扫视幅度、扫视速度等眼动指标分别衰退了37.83%、27.58%、23.80%，皮电均值、心率增长率和SDNN心理生理指标分别衰退了57.67%、20.08%和29.14%，转向熵、车速控制和制动反应时间操作行为指标分别衰退了32.81%、20.34%和49.48%，风险敏感度、判断阈值和风险反应时间风险感知指标分别衰退了13.70%、8.66%和31.80%。通过对风险情境下老年驾驶人的各类行为特性进行详细分析，确定了老年驾驶人各类行为的衰退情况，对老年驾驶人行为特性的研究具有一定借鉴意义。

Behavioral Characteristics of Older Drivers Based on Risk Perception

The objectives of this study are to investigate the differences between the behavioral characteristics, such as eye movement, psychophysiology, driving operation, and risk perception, of elderly drivers and those of middle-aged and young drivers and determine the decline in the behavioral characteristics of elderly drivers. Five driving simulation experiments at different risk levels were designed and performed using eye trackers, physiological instruments, and driving simulators. Thirty-two subjects (17 older and 15 young and middle-aged persons) were selected to participate in the experiments, and the eye movements, physiology, and driving behavior data were collected. Drivers' eye movement indicators, such as stare, saccade, and heart rate variation, psychophysiological indicators, such as skin electricity, operational behavior indicators, such as braking, steering, risk response, and sensitivity, and risk perception behavioral indicators were compared and analyzed. The analysis results show that drivers' characteristics exhibit a particular variation with increased risk levels. With an increase in the risk level, the driver gaze duration, heart rate, galvanic skin sensitivity index, and risk increase, while the scanning index, heart rate variation index, standard deviation of NN interval (SDNN), braking time, and risk response time decrease. These results indicate that the more significant the risk, the greater the driver's attention and sensitivity to risk and the earlier the response. In addition, a higher degree of psychological stress and more effort are required. Compared to data obtained for young and middle-aged drivers, eye movement indexes for elderly drivers, such as the gaze duration, saccade amplitude, and scanning speed, decrease by 37.83%, 27.58%, and 23.80%, respectively, and the galvanic skin average index, heart rate increase index, and SDNN decrease by 57.67%, 20.08%, and 29.14%, respectively. Correspondingly, the steering entropy, speed control, and braking reaction time indexes decrease by 32.81%, 20.34%, and 49.48%, and the sensitivity and other indicators, judgment threshold, and risk response time decreased by 13.7%, 8.66%, and 31.80%, respectively.