CNRS Toulouse

http://www.cnrs.fr/


Cooperative surveillance and environment monitoring by heterogeneous teams of unmanned aerial vehicles (Kooperativní dohled a senzorické snímání heterogenními týmy bezpilotních vzdušných a pozemních prostředků)

The main objective of the proposed project is to design, implement and experimentally evaluate a complex heterogeneous system of fixed-wing unmanned aerial vehicles (UAVs), vertical take-off and landing micro aerial vehicles (MAVs) and unmanned ground vehicles (UGVs) designed for cooperative surveillance and environment monitoring. Taking advantage of expertise of Centre national de la recherche scientifique (CNRS) partner in deployment of UAVs in environment monitoring applications and expertise of Multi-robot Systems (MRS) group in design of techniques for MAVs flying in GPS-denied environment, we aim to combine abilities of UAVs to cover large areas under surveillance and MAVs to operate in GPS-denied areas. In addition, both partners have a long-term experience with integration of UGVs into teams of aerial vehicles, which also increases deployability of the system and its operation time. The aim of the project is to design methodologies that provide motion planning for UAV-MAV-UGV teams in a cooperative manner and that enable fusion of low-resolution data gathered during flights of fixed-wings UAVs in higher altitudes together with high-resolution information provided from MAVs and UGVs simultaneously observing areas in which the rough overview from UAVs is insufficient.

 

Cooperation with Simon Lacroix from Centre national de la recherche scientifique (CNRS), France: Simon Lacroix, Antonio Franchi, Juan Cortes 


Localization of UAVs based on Blinking Ultraviolet Markers

Mutual relative localization is a crucial tool for formation preservation, swarming and cooperative task completion in scenarios in which UAVs share working space in small relative distances. In most current systems of compact UAV swarms the localization of particular UAVs is based on the data obtained from motion capture systems for indoor experiments or on precise RTK-GNSS data outdoor. Such an external infrastructure is unavailable in most of real multi-UAV applications and often cannot be pre-installed. To account for such situations, as well as to make the system more autonomous, reliance on onboard sensors only is desirable. In the proposed approach, we rely on  ultraviolet LED markers, that emit light in frequencies that are less common in nature than the visible light or infrared radiation, especially in high intensities. These markers are viewed with cameras eqipped with fisheye lenses and UV bandpass filters. This allows for a smaller size of the markers to be sufficient, without burdening the processing resources. Thus the proposed system aspires to be an enabling technology for deployment of large swarms of possibly micro-scale aerial vehicles in real world conditions and without any dependency on an external infrastructure. In order to account for visual anonymity of the markers in UV spectrum, the identity of the markers is encoded in blinking frequencies. A novel method for tracking such disappearing markers in an image was developped, based on 3D time-position Hough transform.

 

Fast Mutual Relative Localization of UAVs using Ultraviolet LED markers

A demonstration of our system for relative mutual localization of UAVs. It exploits there are not many strong natural sources of UV light, allowing for easy and efficient segmentation, detection and localization of artificial UV sources. The intended use is in stabilization and control of UAV swarms in arbitrary environment.

Mutual Localization of UAVs based on Blinking Ultraviolet Markers and 3D Time-Position Hough Transform

Mutual relative localization is a crucial tool for formation preservation, swarming and cooperative task completion in scenarios in which UAVs share working space in small relative distances. In most current systems of compact UAV swarms the localization of particular UAVs is based on the data obtained from motion capture systems for indoor experiments or on precise RTK-GNSS data outdoor. Such an external infrastructure is unavailable in most of real multiUAV applications and often cannot be pre-installed. To account for such situations, as well as to make the system more autonomous, reliance on onboard sensors only is desirable. In the proposed approach, we rely on ultraviolet LED markers, that emit light in frequencies that are less common in nature than the visible light or infrared radiation, especially in high intensities. Additionally, common camera sensors are sensitive to ultraviolet light, making the addition of a filter the only necessary modification, keeping the platform low-cost, which is one of the key requirements on swarm systems. This also allows for a smaller size of the markers to be sufficient, without burdening the processing resources. Thus the proposed system aspires to be an enabling technology for deployment of large swarms of possibly micro-scale aerial vehicles in real world conditions and without any dependency on an external infrastructure.


Publications

  1. R Pěnička, M Saska, C Reymann and S Lacroix. Reactive Dubins Traveling Salesman Problem for Replanning of Information Gathering by UAVs. In ECMR. 2017. URL BibTeX

    @inproceedings{penicka_ecmr_rdtsp,
    	author = "R. Pěnička and M. Saska and C. Reymann and S. Lacroix",
    	title = "Reactive Dubins Traveling Salesman Problem for Replanning of Information Gathering by UAVs",
    	booktitle = "ECMR",
    	year = 2017,
    	url = "http://mrs.felk.cvut.cz/ecmr17rdtsp"
    }
    
  2. V Walter, M Saska and A Franchi. Fast mutual relative localization of uavs using ultraviolet led markers. In 2018 International Conference of Unmanned Aircraft System (ICUAS). 2018. BibTeX

    @inproceedings{walter_laas_cnrs,
    	author = "V. Walter and M. Saska and A. Franchi",
    	title = "Fast mutual relative localization of uavs using ultraviolet led markers",
    	booktitle = "2018 International Conference of Unmanned Aircraft System (ICUAS)",
    	year = 2018,
    	note = "accepted to ICUAS 2018"
    }
    
  3. V Walter, N Staub, M Saska and A Franchi. Mutual localization of uavs based on blinking ultraviolet markers and 3d time-position Hough transform. In 2018 International Conference on Automation Science and Engineering (CASE). 2018. BibTeX

    @inproceedings{walter_laas_cnrs_hought,
    	author = "V. Walter and N. Staub and M. Saska and A. Franchi",
    	title = "Mutual localization of uavs based on blinking ultraviolet markers and 3d time-position Hough transform",
    	booktitle = "2018 International Conference on Automation Science and Engineering (CASE)",
    	year = 2018,
    	note = "submitted to CASE 2018"
    }