EGNSS usage as enabling technology

GNSS represents an essential technology as it allows to realise more efficient and reliable operations. To clarify this concept, it is noteworthy that Search and Rescue activities request

Efficiency (Speed of handling operations), as few minutes in these dramatic emergency situations may represent the difference between life and death for localised survivors.
Reliability, as contingent platform outages may cause the mission failure
Operations Continuity, where missions may last even several hours starting from ship departure to arrival at the harbour.

Moreover, the RPAS has to operate in a Dynamic environment; flying tethered to a ship moving (with a velocity of several m/s) over the sea and having position and attitude quickly and unpredictably varying over time.
Having in mind the above considerations, now it is evident the importance of the accurate evaluation about the baseline between the RPAS and the hangar that are linked by means of an extensible (not fixed) cable. During current experimental activities (documented in section 1.3.1) we’re experiencing as having the possibility to monitor the baseline can provide a significant improvement with clear impact in reliability (it avoids excessive mechanical stress to extensible cable) and efficiency of operations (above all during cable deployment and winding).

Moreover, RPAS semi-automatic take-off and landing are critical phase too as performed on board a ship, which is moving. More importantly, the landing area is narrow on a ship, and interference related to the maritime environment due to wind disturbance and wave motions varies greatly, making maritime RPAS landings quite difficult. In order to land RPAS in such a rapidly changing environment requires a high-precision navigation system on-board RPAS.

According the Joint Precision Approach and Landing System (JPALS), the requirements of shipboard landing include vertical accuracy on the order of 0.3 meters, and the requirement for the vertical protection level is 1.1 meters. To meet these accuracy requirements, the consortium is looking to investigate the use of RTK. This focus is particularly interesting as the claimed performances

have to be reached in a dynamic environment such that it involves moving base RTK that makes it very challenging to meet high positioning accuracy requirements. In this framework, the SARA project will be an important occasion to verify these techniques and to confirm results that are preliminary documented in existing literature.

Considering the aforementioned challenges, the EGNSS technology represents an essential asset and it is noteworthy that EGNSS receivers installed on board the RPAS may also allow to better evaluate the attitude and in particular the azimuth which is important to detect the survivors position with reference to the ship location.

What is EGNSS, Galileo and EGNOS?

  • EGNSS is the European Global Navigation Satellite System and includes both Galileo and EGNOS.
  • Galileo is the European Global Navigation Satellite Constellation.
  • The European Geostationary Navigation Overlay Service (EGNOS) is Europe’s regional satellite-based augmentation system (SBAS) that is used to improve the performance of GNSSs, such as GPS and Galileo.
  • More information on Galileo and EGNOS can be found on gsa.europa.eu

This project has received funding from the European GNSS Agency (grant agreement No 776099),
under the European Union’s Horizon 2020 research and innovation programme GALILEO-3-2017.