Abstract The risk toward human lives in situations involving chemical, biological, radiological, and nuclear (CBRN) threats can be mitigated or even neutralized by deploying carrying a suite of suitable sensors. Furthermore, mobile robots open up the possibility for automated radiological field surveys and monitoring operations, which have important applications in scenarios with CBRN threats. A path planner is one of the essential tools required for these robots to perform their tasks autonomously. Moreover, sophisticated path planners can greatly increase the efficiency of monitoring tasks by maximizing the information gathered in the minimum amount of time. This work proposes an informative path planner as an instrument to efficiently estimate maps of scalar quantities (e.g., radiation intensity, chemical concentration), motivated by applications in radiological inspection. The proposed path planner models the path with B-splines, enabling planning in continuous space. A Gaussian Process with a squared exponential kernel is used to model the underlying field. A modified form of mutual information, estimated from the Gaussian Process, is maximized to determine the most informative path, additionally rewarding observations made in regions where the field magnitude is large (e.g., near a radioactive source). A maximum likelihood estimator for source parameters is used to demonstrate that the proposed solution increases the accuracy of the estimated source positions. Simulation results show that the informative path planner adapts to non-convex environments and increases the number of observations made close to radioactive sources while avoiding obstacles.

中文翻译：

---

非凸场景中放射调查的探索-利用权衡信息路径规划器

摘要 在涉及化学、生物、放射和核 (CBRN) 威胁的情况下，可以通过部署携带一套合适的传感器来减轻甚至消除对人类生命的风险。此外，移动机器人为自动化放射现场调查和监测操作开辟了可能性，这在存在 CBRN 威胁的场景中具有重要应用。路径规划器是这些机器人自主执行任务所需的基本工具之一。此外，复杂的路径规划器可以通过在最短的时间内最大限度地收集信息来大大提高监控任务的效率。这项工作提出了一种信息丰富的路径规划器，作为一种有效估计标量图（例如辐射强度、化学浓度）的工具，受放射学检测应用的启发。建议的路径规划器使用 B 样条对路径进行建模，从而能够在连续空间中进行规划。具有平方指数内核的高斯过程用于对基础场进行建模。根据高斯过程估计的一种修正形式的互信息被最大化以确定信息最丰富的路径，另外奖励在场强大的区域（例如，靠近放射源）进行的观察。源参数的最大似然估计器用于证明所提出的解决方案提高了估计源位置的准确性。仿真结果表明，信息化路径规划器适应非凸环境，在避开障碍物的同时增加了靠近放射源的观测次数。