通过自动交通事件检测保证挪威隧道的安全
FLIR 被选中为挪威新建的 Hundvåg 和 Eiganes 隧道提供带嵌入自动交通事件检测 (AID) 的智能双视摄像头。这些摄像头现在可以提醒隧道运营商注意可能发生的各种交通事件，包括停车、货物丢失和行人，以便应急服务机构能够迅速作出反应。
挪威的地理条件很复杂。多峡湾、冰川和山脉的地形使得无天然障碍旅行成为一种挑战，这也是为什么该国有如此多的隧道。Ryfast 项目是挪威迄今为止较大的道路项目，也是该国新增加的隧道基础设施之一，从 Stavanger 市通向 Strand 市。
Ryfast 项目由三段隧道组成。长 14.4 公里，从 Tau 村至 Hundvåg 岛的 Ryfylke 隧道已于 2019 年 12 月通车。长 5.5 公里，从 Hundvåg 至 Stavanger 的 Hundvåg 隧道已于 2020 年 4 月通车。后者与 3.7 公里长的 Eiganes 隧道相连，该隧道从 Stavanger 市下方穿过，是 E39 沿海高速公路的一部分。
繁忙交通下的安全
在挪威公共道路管理局 (NPRA) 和隧道承包商们为 Hundvåg 和 Eiganes 隧道寻找可靠的隧道安全系统时，他们必须遵守与该组织以严格而著称的高安全标准。考虑到 Hundvåg 和 Eiganes 这两条双孔隧道的交通很繁忙（每日车流量分别为 10,000 和 35,000 辆），这一点尤其关键。
两条隧道均选择北欧系统集成商 Trafsys 来提供交通控制与监控系统、视频监控 (CCTV) 和自动交通事件检测 (AID) 等。Trafsys 选择由 FLIR Systems 公司在两家公司多年的隧道安全项目经验基础上提供 AID 摄像头技术。
“我们早就确信 FLIR 的交通事件检测系统很稳定，因为我们在之前的隧道项目中使用过这些产品，”Trafsys, AS 部门经理 Knut-Olav Bjelland 说。“凭借着强大的检测算法，FLIR 视觉交通摄像头的性能已在全球的隧道项目中得到证明。有了 FLIR 的双视摄像头，我们能将公司成熟的视频分析与热成像相结合。”
集视觉与热成像为一体的摄像头
Trafsys 选择了 FLIR ITS 自动交通事件检测双视摄像头，它将热像仪和视觉摄像头与先进的视频分析相结合。Hundvåg 和 Eiganes 隧道一共安装了 332 台 FLIR 摄像头。
热像仪的使用已证明在隧道的入口和出口尤其有用。那里的阴影或阳光直射可能限制可见光摄像头的视野，因而会干扰交通检测。由于热像仪检测的是热，而不是光，也就不存在这种问题，因此可以全天候 (24/7) 检测交通。
Hundvåg 和 Eiganes 隧道内安装了 332 个 FLIR ITS 自动交通事件检测双视摄像头。
“看看 Hundvåg 和 Eiganes 隧道的复杂地形，你就知道像 FLIR ITS 系列自动交通事件检测双视摄像头系统是高效的技术选择，”Knut-Olav 说。“两条隧道都有许多弯道和转弯，因此，在许多不同的位置都需要合适的检测系统。”
“这种摄像头的日常表现非常出色，”NPRA 的施工/维护经理 Anders Helle 说。“我们可以在控制室的热图像上清楚地观察检测到的交通事件，从而缩短了了解情况的时间并加快了决策过程。考虑到该系统的可靠性、性能和较低的误报率，我们肯定会推荐采用 FLIR 双视摄像头来进行自动交通事件检测。”
“我们很荣幸能被这条主要隧道的安全项目选中，”FLIR Systems 业务发展总监 Sukhdev Bhogal 说。“这是我们的 ITS 交通事件自动检测双视摄像头首次如此大量安装，我们期待能在该地区更多的隧道提高通行安全性。”
FLIR ITS 系列双 AID 摄像头可检测到停车、车速突然下降、逆行、行人、坠落物和火灾。
早期火灾探测
“除了 FLIR 一贯出色的检测性能外，由同一家供应商提供视觉摄像头和热像仪只有好处没有坏处，”Knut-Olav 说。“将两个摄像头组合成一个检测单元，是一种非常紧凑的解决方案，布线也更加简单。”
双摄像头火灾检测功能也已开启，以展示在明火出现数秒内进行早期探测的能力。这样，交通运营商可以立即关闭隧道，并采取措施快速灭火。FLIR热像仪的热成像技术还能透过烟雾，帮助运营商在充满烟雾的隧道中检测行人和车辆。
2020 年 7 月，当一辆车在 Hundvåg 隧道内失火时，火灾检测功能证明了其有效性。FLIR ITS 双热成像 AID 摄像头在第一次发出停车和行人警告后，在明火出现后的 7 秒内就检测到火情。
Visible and Thermal in One Camera
Trafsys chose FLIR ITS Series Dual AID cameras, which combine a thermal and visual camera with advanced video analytics. In total, 332 FLIR cameras have been installed in the Hundvåg and Eiganes tunnels combined.
The use of thermal imaging cameras has especially proven valuable for tunnel entrances and exits. There, shadows or direct sunlight could obstruct the view of the visible-light camera and therefore disturb traffic detection. Because they detect heat, not light, thermal cameras have no issues with these phenomena and as a result, they can detect traffic 24/7 and in all weather conditions.
332 FLIR ITS Dual AID cameras have been installed in the Hundvåg and Eiganes tunnels.
“When you look at the complex topography of the Hundvåg and Eiganes tunnels, a camera system like the FLIR ITS Series Dual AID is the most efficient technology choice,” says Knut-Olav. “And with the many bends and turns in both tunnels, you need appropriate detection systems at many different positions.”
“The cameras’ daily performance is excellent,” says Anders Helle, Construction/Maintenance Manager at NPRA. “We can clearly see the detected incidents on the thermal image in our control room, which reduces the time to understand the situation and speeds up our decision-making process. Based on the system’s reliability, performance, and low unwanted alarm rate, we would definitely recommend the FLIR dual-vision camera for automatic incident detection.”
“We are honored to be selected for this major tunnel safety project,” says Sukhdev Bhogal, Business Development Director at FLIR Systems. “It is the first time that our ITS Dual AID cameras have been deployed in such large numbers, and we are looking forward to making more tunnels in the region a safer place to travel through.”
The FLIR ITS Series Dual AID detects stopped vehicles, sudden speed drops, wrong-way drivers, pedestrians, fallen objects, and fires. Copyright Norwegian Public Road Administration (NPRA)
Early Fire Detection
“Apart from the great detection performance we are used to from FLIR, having a combined visual and thermal camera from one vendor has nothing but benefits,” says Knut-Olav. “Combining both cameras into one detection unit makes it a very compact solution, and cabling is also much simpler.”
The dual cameras’ fire detection functionality has also been switched on to demonstrate the early detection capability within seconds of the appearance of visible flames. This allows traffic operators to immediately close the tunnel and take action to quickly extinguish the fire. The thermal technology from FLIR cameras also sees through smoke, helping operators detect pedestrians and vehicles in a smoke-filled tunnel.
The fire detection functionality proved its effectiveness when a car caught fire in the Hundvåg tunnel in July 2020. The FLIR ITS Dual thermal AID camera picked up the fire within 7 seconds after visible flames appeared, following its first alert for a stopped vehicle and pedestrians.
Some assets compiled in the featured image and video are copyright Norwegian Public Road Administration (NPRA)
