The protection and restoration of the biosphere is crucial for human resilience and well-being, but the scarcity of data on the status and distribution of biodiversity puts these efforts at risk. DNA released into the environment by organisms, i.e., environmental DNA (eDNA), can be used to monitor biodiversity in a scalable manner if equipped with the appropriate tool. However, the collection of eDNA in terrestrial environments remains a challenge because of the many potential surfaces and sources that need to be surveyed and their limited accessibility. Here, we propose to survey biodiversity by sampling eDNA on the outer branches of tree canopies with an aerial robot. The drone combines a force-sensing cage with a haptic-based control strategy to establish and maintain contact with the upper surface of the branches. Surface eDNA is then collected using an adhesive surface integrated in the cage of the drone. We show that the drone can autonomously land on a variety of branches with stiffnesses between 1 and 10 3 newton/meter without prior knowledge of their structural stiffness and with robustness to linear and angular misalignments. Validation in the natural environment demonstrates that our method is successful in detecting animal species, including arthropods and vertebrates. Combining robotics with eDNA sampling from a variety of unreachable aboveground substrates can offer a solution for broad-scale monitoring of biodiversity.

中文翻译：

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无人机辅助从树枝中收集环境 DNA 用于生物多样性监测

生物圈的保护和恢复对于人类的复原力和福祉至关重要，但生物多样性状况和分布数据的匮乏使这些努力面临风险。如果配备适当的工具，生物体释放到环境中的 DNA，即环境 DNA (eDNA)，可用于以可扩展的方式监测生物多样性。然而，在陆地环境中收集 eDNA 仍然是一个挑战，因为需要调查的潜在表面和来源很多，而且它们的可及性有限。在这里，我们建议通过使用空中机器人在树冠外枝上采样 eDNA 来调查生物多样性。无人机将力感应笼与基于触觉的控制策略相结合，以建立并保持与树枝上表面的接触。然后使用集成在无人机笼中的粘性表面收集表面 eDNA。我们展示了无人机可以自主降落在各种刚度在 1 到 10 之间的树枝上3个牛顿/米，无需事先了解其结构刚度，并且对线性和角度偏差具有鲁棒性。在自然环境中的验证表明我们的方法成功地检测了动物物种，包括节肢动物和脊椎动物。将机器人技术与来自各种无法到达的地上基质的 eDNA 采样相结合，可以为生物多样性的大规模监测提供解决方案。