Exodronics

We provide innovative tools in the field of Terrestrial Observation through UAVs or drones

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StratoTrans: Roads & Traffic Management from the Sky

Researchers from Exodronics, Eurecat & EACOM publish interim findings

Previous blog entries have reported the project Kick-off (ref 08-04-2020), its objectives (ref 26-02-2020) and initial achievements (ref 14-10-2020). This article, summarising the latest results, is a synthesis extracted from the article accepted for publication by the prestigious journal “Drones”.  

StratoTrans: Unmanned Aerial System (UAS) 4G communication framework …

Entitled “StratoTrans: Unmanned Aerial System (UAS) 4G communication framework applied to the monitoring of road traffic and linear infrastructure” the paper describes the operational solution developed to directly connect drones to internet by means of 4G telecommunications. 

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Figure 1: A) On board hardware devices. B) Complete hardware implementation in the EXO C2-L+ fixed wing drone. C) The implementation is adaptable to multicopters and fixed-wing drones, useful for different purposes.

The novelty of this work is the application of 4G connection to link the drone directly to a data server where video (in this case to monitor road traffic) and imagery (to monitor road infrastructures) are processed. However, this framework is appliable to any other monitoring purpose where the goal is to send real-time video or imagery to the headquarters where the drone data is processed, analyzed, and exploited. 

Key points, such as the hardware to use, the data stream, and the network coverage, are covered – but also the complete resulting implementation of the applied UAS communication system through a Virtual Private Network (VPN) featuring a long-range telemetry high-capacity video link (up to 15 Mbps, 720p video at 30fps with 250 ms of latency). 

…Applied to the monitoring of roads infrastructure…

The paper goes on to describe the data acquired by the prototype drone; this includes telemetry and imagery but with a focus on video transmission. 

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Figure 2: The drone tracks a flight plan following the linear infrastructure and takes images. The imagery is saved in EXO Data dockers and postprocessed using photogrammetric, remote sensing and GIS software. The infrastructure manager can retrieve information for conservation, maintenance or exploitation purposes.  

The imagery downloads and storage is also performed thorough internet, although the Structure from Motion postprocessing is not real-time due to photogrammetric workflows. 

… and to road traffic analyses

This platform is set-up for the real-time exploitation of the video, obtaining key information for traffic managers such as vehicle tracking, vehicle classification, speed estimation, and roundabout in-out matrices.

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Figure 3: Traffic flow Computer Vision algorithms process the video received in EXO Data server. This allows near real-time information for traffic management, such as in-out roundabout matrix (segmented by object class) and speed estimation.

Conclusions

The paper describes a real-case application of drone connection to internet thorough 4G network, but it can be adapted to other applications. Although 5G will – in time – surpass 4G capacities, the described framework can enhance drone performance using the telecoms that are generally available today. 

Author: Simon Hayes, Consultant, Global-Local Projects