“One of the key benefits of rotary wing aircraft is their flexibility to operate from smallest start & landing sites”, Lars Zander, Swiss UAV’s CSO says. “With our new system, we are now able to perform fully automatic takeoffs & landings with up to now unknown precision and reliability – even if the ground is moving and space is limited!”
Currently, automated manoeuvres for VTOL UA such as landing on small vessels or on the back of moving trucks are significantly limited by the accuracy & reliability of available sensor systems – traditionally GPS combined with inertial augmentation.
“We see an increasing demand to operate our UAVs fully automatically, also from moving ground. We decided to incorporate the Astrium solution that enables us to perform relative navigation with an accuracy of less than 20cm even in areas with high RF multipath conditions”, Zander explains.
After successful joint flight trials on Board of a German Coast Guard Vessel last autumn, Swiss UAV now signed a respective contract with EADS Astrium. The contract foresees the full incorporation of Astrium’s DeckFinder High-Precision Local Navigation System into the Swiss UAV Neo and its modernized avionic suite for UAV systems.
DeckFinder is a GPS independent, relative navigation system that provides the UAV autopilot with the relevant relative positioning & heading information during start, final approach & landing. DeckFinder consists of a ground segment of six locally deployed ‘Satellites’, and a corresponding airborne receiver.
DeckFinder system concept: GNSS independent ranging signals for high accuracy near-field navigation, with an accuracy to safely “hit-the-grid”
“During the operational tests we performed during the last months, we have realized that having a sensor system like DeckFinder will provide us with several new, unique capabilities, that both enhance the applications spectrum of our Neo UAV, as well as the safety and reliability of operations during critical phases of the flight.”
Based on the DeckFinder generated information, the Neo series can now be safely operated from ships or trucks. As the DeckFinder System calculates the relevant navigation information for start and landing directly inside the UAV flight control computer, landings under emergency conditions could still be performed, even in potential communication link-loss situations. As DeckFinder does not rely on GPS, it enables the UAV to continue approach & landing also in GPS jamming scenarios. If DeckFinder is operated with two Antennas on the UAV, it also provides the autopilot with attitude information – a feature that is especially relevant if the UAV’s magnetometers are disturbed, as they have been during the tests performed on the German Coast Guard Vessel last year.
In order to operate up to high sea states, the DeckFinder signals have been designed to be weather independent, and the high update rate provided to the avionics system enables the UAV to also cope with highly dynamic situations.
Swiss UAV will have completed the integration of DeckFinder into its new avionics suite within the next months. This upgrade goes hand-in-hand with a broader avionics systems upgrade, both on Swiss UAV’s ground and airborne systems. The new Ground Control Station has been redesigned to NATO STANAG standards, and the upgraded Flight Control Unit will provide additional state-of-the art flight modes, one of them being the capability to perform ATOL on moving ground.
Zander: “We have designed a highly innovative, standardized avionics system for our Neo UAV, designed to meet MIL STD 810E. From June 2012 on, we will offer this solution also on the open market, allowing any fixed or rotary wing UAV to upgrade its current capabilities with minimal effort at an affordable price.”