Accurate and safe EGNOS-SoL navigation for UAV-based low-cost SAR operations

The context of CLOSE-SEARCH is that of search-and-rescue (SAR) operations in a number of critical circumstances ranging from outdoor sports to natural or man-made disasters. This context covers a broad range of situations: from position-tagged (geo-referenced) distress calls, to loosely-geo-referenced and non-geo-referenced ones. The proposed search system can be operated day and night in rather inaccessible areas. By systematically flying over a region and through the detection of the body heat, CLOSE-SEARCH is intended to identify survivors or lost people. In other words, CLOSE-SEARCH would be a low-cost and robust system to support the SAR search component in situations where there is only an approximate knowledge of the search area.

The use of unmanned aircraft (UA) for SAR operations is not new. When a small plane crashes in a remote area, a fishing boat is lost at sea, or a hurricane devastates a region, SAR teams must scramble every available resource to scan vast areas for evidence of victims or wreckage. Wilderness Search and Rescue (WiSAR) generally entails searching over large regions in often rugged remote areas. Because of the large regions and potentially limited mobility of ground searchers, WiSAR is an ideal application where small or tactical UA have been used to provide aerial imagery of the search region.

Description

CLOSE-SEARCH will innovate in the following areas:

• low-cost search component of a SAR;
• automatic GPS-EGNOS-based small unmanned helicopter flight control;
• hyper-redundant integrated navigation concept with altimeters, redundant-INS, GNSS-EGNOS/SoL;
• hyper-redundant integrated navigation implementation with altimeters, redundant-INS, GPS-EGNOS;
• analysis of the contribution of a multi-constellation GNSS and Galileo SoL service;
• integration with 3D geospatial databases.

Different teams are brought together in this project: technologists, scientists, 3D spatial data providers and a SAR end-user. In so doing, the team guarantees that there is an impact –a technology push influence – of recent and forthcoming evolutions of navigational technology on the market, that there is an impact in the way 3D spatial information should be represented (the long overdue new 3D models beyond simple DEM and DSM) and that there is feedback – a market pull influence – on the actual needs of the final user. 
The team members are contributing hardware and software that will not only deliver a prototype to demonstrate end-to-end functionality, but also to indicate the characteristics of a low-cost operations-ready system.

Objectives

The goal of CLOSE-SEARCH is to integrate, in a small unmanned aircraft, a thermal imaging sensor and a multi-sensor BA/RINS/GPS-EGNOS-based navigation system with an Autonomous Integrity Monitoring (AIM) capability, to support the search component of search-and-rescue (SAR) operations in remote, difficult-to-access areas and/or in time-critical situations. The proposed integration will result in a hardware and software prototype that will demonstrate an end-to-end functionality. For reasons of manoeuvrability, the proposed UA will be a helicopter.

It is also the goal of CLOSE-SEARCH to demonstrate the added value of a future multi-constellation-augmented GNSS configuration, like Galileo/GPS-EGNOS. Two key target attributes of the proposed concept are ultra-safe navigation and overall low cost, so it can be safely and widely implemented. A simple piece of equipment available in ski resorts, tourist areas, mountaineering clubs and local civil protection premises is also envisioned.