As we witness the fast growth of the Unmanned Aerial Vehicles (UAVs) field, new applications and services emerge at a rapid pace. Above all, the interest in groups of UAVs working together (swarms) is gaining momentum. This interest emerges since swarms are able to undertake more sophisticated tasks. Furthermore, they can also increase task performance and/or robustness. However, organizing a multi-UAV flight is not easy, involving challenges in terms of (i) swarm formation definition, (ii) takeoff procedure, (iii) in-flight coordination, (iv) communication between the swarm elements, (v) swarm layout reconfiguration, (vi) handling the loss of swarms elements, and (vii) controlled landing. These and other issues still hold back the mainstream adoption of swarms in sectors such as agriculture, border surveillance, and parcel delivery.

In this work we provide solutions for two of the main critical challenges: (a) swarm layout reconfiguration, and (b) handling the loss of swarm elements. A wide set of experiments were made using our own realistic UAV emulation tool (ArduSim) in order to validate our proposals. The experiments show that the chances of facing collisions during the reconfiguration are greatly reduced even in error-prone scenarios, and that, in many cases, the loss of a UAV is handled seamlessly; otherwise (in the worst-case scenarios) a delay of just a few seconds is introduced. Additionally, this work addresses cases where, due to the lack of proper communication between the swarm elements, a swarm splits up. Experiments show that with our swarm resilience mechanisms those cases are inherently solved by creating autonomous sub-swarms which will then complete their part of the mission independently.

随着我们目睹无人飞行器（UAV）领域的快速增长，新的应用和服务正在迅速兴起。最重要的是，人们对共同协作（群居）的无人机群体的兴趣正在增强。由于人们有能力执行更复杂的任务，因此产生了这种兴趣。此外，它们还可以提高任务性能和/或鲁棒性。但是，组织一次多次无人机飞行并不容易，这涉及到以下方面的挑战：（i）编队定义，（ii）起飞程序，（iii）飞行中的协调，（iv）编队要素之间的通信，（v）重新配置群集布局，（vi）处理群集元素的丢失，以及（vii）控制着陆。这些问题和其他问题仍然阻碍了在农业，边境监视和包裹运送等部门中大量采用蜂群。

在这项工作中，我们提供了两个主要挑战的解决方案：（a）群集布局重新配置，以及（b）处理群集元素的丢失。为了验证我们的建议，使用我们自己的逼真的无人机仿真工具（ArduSim）进行了广泛的实验。实验表明，即使在容易出错的情况下，在重新配置过程中遇到碰撞的机会也大大减少了，而且在许多情况下，无人机的损失得到了无缝处理。否则（在最坏的情况下）会引入仅几秒钟的延迟。另外，这项工作解决了由于虫群元素之间缺乏适当通信而导致虫群分裂的情况。