毗邻隧道连接段遮光棚对驾驶人视觉负荷影响试验研究

Influence of Shading Shed at Connection Section Between Two Tunnels on Visual Load of Drivers

为研究毗邻隧道连接段设置遮光棚以及首隧道长度差异对驾驶人视觉适应性和负荷特性的影响,招募32名驾驶人于厦蓉高速贵州段的毗邻隧道进行实车试验,通过眼动仪采集并导出驾驶人在连接段区域的瞳孔变化特性数据。运用瞳孔面积变化与瞳孔面积平均变化速率分析驾驶人的眼动规律;以瞳孔面积最大瞬态速度值(MTPA)为指标,评价驾驶人在毗邻隧道连接段区域的视觉负荷程度,采用单因素方差分析对MTPA进行差异性显著检验。研究结果表明:1)当连接段设置有遮光棚时,驾驶人的瞳孔面积变化较为平稳,瞳孔面积平均变化速率的波动范围明显缩小,主要在-2.0~2.0 mm^(2)/s,驾驶人的MTPA平均降低了25.1%;2)连接段均设有遮光棚时,首隧道为长隧道的场景将使出口区域驾驶人瞳孔面积提前50 m出现下降趋势,在首隧道出口区域的MTPA显著高于首隧道为短隧道的场景,视觉负荷上升了30.1%,但在次隧道入口区域的负荷却下降了27.1%。研究发现:毗邻隧道连接段设置遮光棚可以提高驾驶人对光环境变化的适应能力,缓解明暗转换对视觉的刺激,有效降低驾驶人的视觉负荷,同时首隧道长度的差异会影响驾驶人对光环境变化的适应性。

A total of 32 subjects are recruited to conduct real vehicle tests in two adjacent tunnels of the Guizhou section of the Xiamen-Chengdu expressway to explore the influence of shading shed at the connection section between two tunnels and the length difference of the upstream tunnel on drivers′visual adaptability and load characteristics.Then,the data of pupil variation characteristics are collected and exported by the eye tracker.Further,the eye movement rule of drivers is analyzed by the pupil area change and average change rate.Finally,the maximum transient velocity of pupil area(MTPA)is used as an index to evaluate the driver′s visual load degree in the connection section of two tunnels,and the one-way analysis of variance is used to test the difference of MTPA.Research results reveal the following:(1)When the connection section is equipped with a shading shed,the drivers′pupil area changes more smoothly,and the varying rate of the pupil area is also significantly reduced,mainly in the-2.0~2.0 mm^(2)·s^(-1) range.Moreover,the drivers′MTPA is reduced by an average of 25.1%.(2)When the connection section is equipped with a shading shed and the upstream tunnel is a long tunnel,the pupil area of drivers in the exit zone will decrease by 50 m in advance.Furthermore,the MTPA of the drivers at the exit zone of the upstream tunnel is significantly higher than that of the upstream tunnel when it is a short tunnel,with a 30.1%increase in visual load but a 27.1%decrease in visual load in the downstream tunnel entrance zone.It is concluded that the shading shed at the connection section between two tunnels can improve drivers′adaptability to changes in light environment and effectively reduce drivers′visual load.In addition,the length difference of the upstream tunnels will affect drivers′adaptability to the change in the light environment.