The US Army is exploring development of a high speed obstacle and collision avoidance system for small UAVs operating in urban areas.

A solicitation for concept development, released as part of the latest round of the US small business innovation research programme, calls for sensors that would allow UAVs to operate at speed in complex environments. The same lightweight suite is envisaged as being able to provide small UAVs with a sense and avoid capability for airspace deconfliction and integration.

Solicitation documents describe flight in urban areas, mountainous regions and in crowded airspace as “one of the biggest challenges for autonomous UAVs....Current technologies limit the velocities at which UAVs can travel in such complex environments. A slow UAV is not a very survivable UAV.

“Current technologies also are too large and require more power than typically allowable on small UAVs. These factors limit the potential that exists for using small UAVs at their most appropriate best: agile manoeuvring in complex environments.”

The proposed development effort is focussed on small rotary wing UAVs however the technology is seen as also being potentially applicable to fixed wing types. Later phases of the proposed development programme would concentrate on the US Army Future Combat System UAVs.

Possible sensor options cited by the solicitation include “GPS position information, terrain data to identify areas of probable obstacles complemented by use real-time higher resolution visual (electro-optical/infra-red, LADAR, synthetic aperture radar, etc.) and non-visual (radio frequency, acoustic, etc) data to detect stationary as well as moving obstacles in its path”.

The stationary and moving obstacle detection method “must support route deconfliction with other non-cooperative manned and unmanned aircraft travelling at speeds in the same order of magnitude as the host UAV.”

The solicitation also says that “an approach that integrates the detection system to a near-horizon route planning approach that would enable it to execute the avoidance manoeuvre autonomously would be highly desirable, although it is not a requirement”.

Key technical challenges identified by the solicitation are the achievement of sufficiently low cost, low weight and lower power sensor suites, as well as the minimisation of latency in sensor data processing to allow the UAV to fly “at or near maximum manoeuvre speeds”.

Proposals are required by 13 June.