Soil moisture monitoring is a fundamental process to enhance agricultural outcomes and to protect the environment. The traditional methods for measuring moisture content in soil are laborious and expensive, and therefore there is a growing interest in developing sensors and technologies which can reduce the effort and costs. In this work, we propose to use an autonomous mobile robot equipped with a state-of-the-art non-contact soil moisture sensor that builds moisture maps on the fly and automatically selects the most optimal sampling locations. The robot is guided by an autonomous exploration strategy driven by the quality of the soil moisture model which indicates areas of the field where the information is less precise. The sensor model follows the Poisson distribution and we demonstrate how to integrate such measurements into the kriging framework. We also investigate a range of different exploration strategies and assess their usefulness through a set of evaluation experiments based on real soil moisture data collected from two different fields. We demonstrate the benefits of using the adaptive measurement interval and adaptive sampling strategies for building better quality soil moisture models. The presented method is general and can be applied to other scenarios where the measured phenomena directly affects the acquisition time and needs to be spatially mapped.

中文翻译：

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基于克里金的机器人探索使用宇宙射线传感器进行土壤水分测绘

土壤水分监测是提高农业成果和保护环境的基本过程。测量土壤水分含量的传统方法既费力又昂贵，因此人们对开发可以减少工作量和成本的传感器和技术越来越感兴趣。在这项工作中，我们建议使用配备了最先进的非接触式土壤湿度传感器的自主移动机器人，该传感器可动态构建湿度图并自动选择最佳采样位置。机器人由自动探索策略引导，该策略由土壤水分模型的质量驱动，该模型指示信息不太精确的田地区域。传感器模型遵循泊松分布，我们演示了如何将此类测量集成到克里金框架中。我们还研究了一系列不同的勘探策略，并通过一组基于从两个不同领域收集的真实土壤水分数据的评估实验来评估它们的实用性。我们展示了使用自适应测量间隔和自适应采样策略构建质量更好的土壤水分模型的好处。所提出的方法是通用的，可以应用于测量现象直接影响采集时间并需要进行空间映射的其他场景。我们还研究了一系列不同的勘探策略，并通过一组基于从两个不同领域收集的真实土壤水分数据的评估实验来评估它们的实用性。我们展示了使用自适应测量间隔和自适应采样策略构建质量更好的土壤水分模型的好处。所提出的方法是通用的，可以应用于测量现象直接影响采集时间并需要进行空间映射的其他场景。我们还研究了一系列不同的勘探策略，并通过一组基于从两个不同领域收集的真实土壤水分数据的评估实验来评估它们的实用性。我们展示了使用自适应测量间隔和自适应采样策略构建质量更好的土壤水分模型的好处。所提出的方法是通用的，可以应用于测量现象直接影响采集时间并需要进行空间映射的其他场景。