城市隧道入口遮阳棚对驾驶人视觉负荷影响试验研究

Experimental Study on the Impact of Sunshades at Urban Tunnel Entrances on Driver′s Visual Load

为研究隧道入口处驾驶人的视觉负荷特性及遮阳棚对驾驶人视觉负荷的影响,选取翔安隧道(有遮阳棚)及胶州湾隧道(无遮阳棚)开展实车试验,采集驾驶人瞳孔面积、注视持续时间、扫视幅度和眨眼频率作为研究参数进行对比分析,同时建立基于因子分析的隧道入口处驾驶人视觉负荷强度评价模型,确定两座隧道入口处驾驶人的视觉负荷程度。研究结果表明:与未设置遮阳棚的隧道相比,设置遮阳棚的隧道驾驶人的瞳孔面积、瞳孔面积变化率均值、注视持续时间和扫视幅度的均值都较小;驾驶人在驶入隧道过程中,瞳孔面积呈逐渐上升的趋势,无遮阳棚隧道驾驶人眨眼频率增加值波动较大,而有遮阳棚隧道驾驶人眨眼频率增加值变化较为平滑;设置遮阳棚可使驾驶人视觉负荷值降低51.85%,对改善隧道入口区域(包括遮阳棚临近段、遮阳棚段、隧道入口段)驾驶人的视觉负荷具有积极意义。

To study the visual load characteristics of drivers at tunnel entrances and the impact of sunshades on visual load,real vehicle experiments were conducted at Xiang′an Tunnel(with the sunshade)and Jiaozhou Bay Tunnel(without the sunshade).Parameters such as pupil area,fixation duration,saccade amplitude,and blink frequency were collected for comparative analysis.A visual load intensity evaluation model for drivers at tunnel entrances was established based on the factor analysis to determine the visual load intensities at the entrances of the two tunnels.The study shows that,compared to tunnels without sunshades,the pupil area,the mean change rate of pupil area,the fixation duration,and the mean saccade amplitude of drivers in tunnels with sunshades are all smaller.As drivers enter the tunnel,the pupil areas gradually increase.The increase in blink frequency fluctuates significantly in tunnels without sunshades,while it changes more smoothly in tunnels with sunshades.Sunshades can reduce the visual load value by 51.85%,which is beneficial for improving the visual load of drivers in the tunnel entrance area(including the adjacent section of the sunshade,the sunshade section,and the tunnel entrance section).