Abstract

Unmanned Aerial Vehicles (UAVs) can be a powerful tool for live (interactive) remote inspection of large-scale structures or areas of interest. Instead of manual, local, and labor-intensive inspections, we envision human operators working together with networks of semi-autonomous UAVs. The current state-of-the-art for low-delay high-throughput inter-vehicle networking relies on Time-Division Multiple Access (TDMA) techniques that require accurate synchronization among all network nodes. In this paper, we propose a delay-tolerant synchronization approach that converges to the correct order of the TDMA slots implemented over COTS WiFi in a fully-distributed way and without resorting to a global clock. This highly flexible solution allows building an ad-hoc aerial network based on a backbone of relaying UAVs. We show several alternatives to achieve this synchronization in a concrete aerial network and compare them in terms of slots’ overlap, throughput, and packet delivery. The results show that these alternatives lead to trade-offs in the referenced metrics. The results also provide insight into the delays caused by buffering in the protocol stack and especially in the WiFi interface.

Highlights

  • Unmanned Aerial Vehicles (UAVs), in particular multirotors, can be used for a myriad of applications such as live remote inspection of large-scale structures, e.g., towers, bridges, pipelines, or of specific areas of interest, e.g., for search and rescue [1] or wild-life surveys [2]

  • We propose a delay-tolerant synchronization approach that converges to the correct order of the Time-Division Multiple Access (TDMA) slots implemented over COTS WiFi in a fully-distributed way and without resorting to a global clock

  • In the case of a network relying on a shared medium, such as Radio Frequency (RF), TDMA provides a separate slot to every transmitter in the network, preventing mutual interference

Read more

Summary

Introduction

Unmanned Aerial Vehicles (UAVs), in particular multirotors, can be used for a myriad of applications such as live (interactive) remote inspection of large-scale structures, e.g., towers, bridges, pipelines, or of specific areas of interest, e.g., for search and rescue [1] or wild-life surveys [2]. An operator at a ground Base Station (BS) defines a remote Area-of-Interest (AoI) and instructs a group of semi-autonomous sensor-capable UAVs to navigate there; secondly, interactive control of the fine position and pose of UAVs is initiated to focus on features of interest; concurrently, a live stream of sensor data from the AoI to the BS is initiated; the necessary communication backbone is established, by means of a complementary autonomous group of relaying UAVs, linking sensor UAVs to the BS

Methods
Results
Conclusion

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.