Guidance Navigation Limited - the use of multibeam laser sensing to provide 3D environment analysis for a position and attitude reference sensor for offshore dynamic vessel or other control systems

许多近海船舶使用基于GPS的动态定位(DP)系统来辅助导航和控制。新的位置测量设备(PME)船级社规则要求在某些操作中使用三个独立的PME。独立的要求是基于常见的故障模式，因此多个GPS不能被视为独立的。目前，与离岸设施有关的船舶近距离定位是通过2D激光或雷达定位系统与船舶DP系统结合使用进行的，这些系统提供x&y坐标。现有设备依赖于专门的靶标，例如固定海上平台上的激光棱镜组，在开始运行之前正确部署和维护，以便能够识别相对位置，见图1。靶标需要仔细定位，以便现有系统正确可靠地运行。由于外部影响，例如其他船只遮挡了现有设备所需的视线或来自其他移动反射设备的错误反射，任何问题往往在操作开始前的关键时期变得明显，偶尔在操作期间也会变得明显。图2说明了一个典型的系统。见APP A中最大的DP船队运营商之一太古集团对问题的确认。船只定位还受到目标相对于传感器位置的可见度的限制，从而限制了进场角度。这可能会阻碍在恶劣天气条件下的作业准入，还经常导致船只排队等待进入，增加了大量的运营成本。目标的位置受到可用的架构的限制，并且可能不是最佳的位置。与这些目标相关的设置和维护成本很高。在平台上定位反射器的要求还增加了安装、维护和责任方面的商业复杂性。在无人驾驶设施中，传感器的定位是一个特殊的挑战。现有系统提供位置的2D平面图，并且无法识别仰角视野中的潜在异常。该项目旨在开发一种多光束激光传感系统，该系统可提供从激光图像(例如，图3)导出的3D位置，以便集成到DP系统中，以实现无目标的海上作业。它将增加操作灵活性，例如进场方向、天气窗，从而使业主获得更高的租赁率和租住率。它能够识别x、y和z场中的异常，降低碰撞风险和随后的成本，并提高安全性。定位能力在船内是自我封闭的。这种灵活性对于更具活力的海上设施来说也很有趣，例如海上建筑工地。它还可以与其他船舶控制系统对接，如稳定性或起重机控制。

Many offshore vessels use GPS based Dynamic Positioning (DP) systems to assist navigationand control. New position measurement equipment (PME) classification society rules for DPvessels require that three independent PME are used during certain operations. Therequirement for independence is based on common failure modes, so multiple GPS cannot becounted as independent. Currently close positioning of vessels in relation to offshoreinstallations is undertaken with 2D laser or radar positioning systems working in conjunctionwith the vessels DP system, these provide x & y coordinates. Existing equipment relies onspecialised targets, e.g. laser prism clusters on fixed offshore platforms, being correctlydeployed and maintained prior to operational commencement to enable the identification ofthe relative location, see Fig 1. The targets need to be carefully positioned in order for existingsystems to function correctly and reliably. Any problems tend to become apparent during thecritical period before operations commence and occasionally during operations, due toexternal influences e.g. other vessels obscuring the line of sight required by existingequipment or false reflections from other mobile reflective devices. Fig 2 illustrates a typicalsystem. See confirmation of issues from Swire Group one of the largest DP fleet operators inApp A. Vessel positioning is also limited by the visibility of the targets in relation to thesensor location, constraining the angle of approach. This may hamper operational access inadverse weather conditions and also often leads to vessels queueing for access, addingsignificant operational costs. The location of targets is limited by available architecture andmay not be optimally sited. There are significant set up and maintenance costs associated withthese targets. The requirement for locating the reflectors on the platform also adds commercialcomplexities, in terms of installing, maintaining and liability. Locating the sensors is aparticular challenge on unmanned installations. Existing systems provide a 2D planar view ofthe position and do not identify potential anomalies in the elevation field of view.The project aims to develop a multibeam laser sensing system that provides the derived 3Dposition from the laser image (see Fig 3 for example) for integration into the DP system toenable offshore operation without targets. It will increase operational flexibility, e.g. directionof approach, weather window, consequently allowing the owners to achieve higher lease andutilisation rates. It enables the identification of anomalies in x,y and z fields reducing the riskof collisions and subsequent costs, and improving safety. The positioning capability is selfcontainedwithin the vessel. The flexibility is additionally interesting for more dynamicoffshore installations such as offshore construction sites. It could also interface with othervessel control systems such as stability or crane control.