ASUNDER - Adaptable Semiautonomous Underwater Decommissioning Sample Retrieval Robot

核工业中有许多遗迹包含被淹没的设施，例如日本福岛第一核电站1号机组的主要容器，以及英国塞拉菲尔德的储水池。这些被淹没的地点往往含有或含有高放射性物质，因此具有极高的危险性。作为这些设施退役战略的一部分，有必要确认这些淹没区域内材料的性质，以便尽可能安全地移走这些材料。无论是为了验证，还是出于其他原因，在某些时候都有必要取出材料的一小部分样本进行基于实验室的测试，这可能涉及确定样本的机械、化学或辐射性能。由于环境的危害性，这样的样本采集不能手动进行。然而，没有能够完成这项任务的机器人系统，因为大多数水下退役切割工具都是为大规模拆除建筑物而开发的，因此不适合执行这项任务。此外，这些工具通常需要固定到被切割的结构上，以适应产生的力。这种方法不能在这种情况下使用。该项目提出了一种新的解决方案，即使用基于无人水下机器人(UUV)的机器人来定位和定位水下刀具，以半自主地取出样品。这样的系统将能够访问几乎任何水下环境，并在其他系统无法获取的情况下提取样本。这个系统将意味着刀具将不需要固定，减少了人工干预的需要，使过程变得更加安全。在粒子悬浮造成的浑浊条件下，将使用声纳数据通过虚拟现实向操作员提供导航。声纳数据还将支持机械手上的成像系统，用于通知和监测本地的切割过程。还将同时评估辐射环境，以便为决策提供信息，例如确定真皮位置或其性质。为了实现这一目标，将开发并集成一种能够估计水下剂量率和中子能谱的新型紧凑型中子传感器，并使用附加的传感和反馈系统来监测机械手关节和末端执行器的位置和方向。这将包括有关机械手上的流体动力载荷的信息。基于机械手的逆动力学，开发并实现了一种自适应的半自主控制算法，该算法将补偿水动力和UUV的运动，以确保切割操作高效地继续进行。末端执行器将包括样品回收工具以及切割工具。这使得这些工具能够协同工作，同时将重量和复杂性降至最低。其目的是使控制战略具有适应性，并允许在退役战略演变过程中根据需要纳入其他工具。该系统将包括一个完整的端到端解决方案，并在日本和英国的实际条件下进行验证。

There are many legacy sites within the nuclear industry that contain facilities that are submerged, such as the primary contain vessels in Unit 1 of the Fukushima Daiichi Nuclear Power Plant in Japan, and the storage ponds at Sellafield in the UK. These submerged sites often contain, or have contained, highly radioactive materials and as such are highly hazardous. As part of the decommissioning strategy of these facilities, it is necessary to confirm the properties of the materials within these submerged areas, so that they can be removed as safely as possible. Whether it be for validation, or other reasons, at some point it is necessary to remove a small sample of the material for lab-based testing, which may involve determining the mechanical, chemical or radiological properties of the sample. Due to the hazardous nature of the environment, such sample collection cannot be conducted manually. However, robotic systems capable of this task are not available, as most cutting tools for underwater decommissioning were developed for the large-scale removal of structures and hence, are not suitable for the task. Also, these tools often need to be secured to the structure being cut to accommodate the forces generated. This methodology cannot be employed in this scenario. This project proposes a new solution, whereby an unmanned underwater vehicle (UUV) based robotic manipulator will be used to position and orientate underwater cutting tools to remove samples semiautonomously. Such a system will be able to access almost any submerged environment and retrieve samples where no other system could. This system would mean that the cutting tool will not need to be secured, reducing the need for manual intervention, making the process much safer. Navigation in the turbid conditions caused by particle suspension will be achieved using sonar data presented to the operator using virtual reality. The sonar data will also support imaging systems on the manipulator used to inform and monitor the cutting process locally. The radiological environment will also be assessed concurrently to inform decision making, such as the identification of the corium position or its nature. To achieve this, a novel compact neutron sensor capable of estimating the dose rate and neutron energy spectrum underwater will be developed and integrated.Additional sensing and feedback systems will be used to monitor the position and orientation of the manipulator joints and end effectors. This will include information about the hydrodynamic loading on the manipulator. An adaptable semiautonomous control algorithm will be developed and implemented based on the inverse dynamics of the manipulator that will compensate for the hydrodynamic forces and the movement of the UUV to ensure the cutting operation continues efficiently. The end effector will incorporate a sample retrieval tool, as well as a cutting tool. This allows the tools to work collaboratively, whilst minimising weight and complexity. It is intended that the control strategy will be adaptable and will allow other tools to be incorporated as required as decommissioning strategies evolve. This system will comprise a complete end-to-end solution, validated in realistic conditions in both Japan and the UK.