Follow-on testing of the Army Aviation and Missile Research, Development and Engineering Center’s (AMRDEC) fly-by-wire Rotorcraft Aircrew Systems Concept Airborne Laboratory, or “RASCAL,” points toward the next generation of unmanned rotorcraft.
“The end result will be software algorithms and supporting sensor and flight control system technologies that enable the development and fielding of rotorcraft with fully autonomous or optionally piloted capabilities,” an AMRDEC spokesperson told Defense Daily.
RASCAL is a JUH-60A Black Hawk Helicopter specially equipped with the H.N. Burns 3D-LZ ladar for terrain sensing. The aircraft is a flying laboratory and used for a wide range of tests. Pilots are onboard to monitor the tests and safely assume control if necessary.
The flights at Aviation Development Directorate and Aeroflightdynamics Directorate (ADD/AFDD) are to advance the technology in rotorcraft autonomy to a technology readiness level that supports the transfer of this technology to the existing fleet or any new Army rotorcraft, the spokesman said in an e-mail response. “Requirements for future vertical lift platforms include the need for optionally piloted vehicles. In the nearer term, we can use this capability to increase the autonomous behavior of today’s manned and unmanned systems.”
This work advances the scientific and engineering knowledge base for autonomous flight systems and reduces technical risk for the development of future Army systems by U.S. industry, the spokesman said.
The work also directly supports the acquisition of future Army rotorcraft or upgrades “by creating a cadre of engineers within RDECOM that have direct engineering experience with rotorcraft autonomy,” the spokesman said. “These engineers will be critical as (subject matter experts) SMEs when acquisition decisions about system upgrades or new rotorcraft are made.”
During the May flight tests, the RASCAL was tested through a series of key maneuvers, obstacles and other events human pilots encounter and react to during flight: Terrain Awareness, Avoid High-Power Lines, Avoid Other Aircraft, Selecting a Landing Area, and Exiting from a Box Canyon. The tests were conducted in the Diablo Range, 40 miles east of San Jose, Calif.
In the RASCAL’s first flight test performed Nov. 5, 2012, AMRDEC personnel successfully demonstrated low-level autonomous behaviors critical to the next generation of unmanned military rotorcraft. These behaviors include obstacle field navigation, or OFN, in complex/cluttered terrain and safe landing area determination, or SLAD.
More testing is on the way.
“ADD/AFDD will continue with testing the Autonomous Flight Control System (AFCS), Obstacle Field Navigation (OFN) and Safe Landing Area Determination (SLAD),” the spokesman said. “We plan to evaluate LADAR sensors with improved capabilities and to continue testing advanced OFN and SLAD algorithms.”
In the near term, he said, “we expect to increase OFN flight speed and increase the SLAD operational tempo.”
Also, flight test demonstrations for DoD stakeholders are also planned.
In the long term, additional areas of autonomy research will be explored, such as co-operative autonomy, multi-sensor fusion, redundant control management, aggressive maneuvering, and operation in a GPS denied environment, the spokesman said.
The ADD/AFDD-developed technologies apply to other rotorcraft as well.
“The origins of the AFCS/OFN/SLAD came from development on Yamaha RMAX remotely piloted helicopters,” said the AMRDEC spokesperson. These are 200-pound radio controlled vehicles that were developed for seeding and spraying in commercial agriculture applications.
The algorithms were transferred to the 15,000-pound JUH-60A RASCAL, and used on the flights that can be viewed on the Army AMCOM YouTube page.
“In addition, the SLAD and OFN algorithms have been packaged for external release and are available for use by U.S. industry on other vehicles. The SLAD algorithm was used in an Army/Lockheed-Martin [LMT]/Kaman [KAMNA] flight demonstration on the K-MAX aircraft in June 2013,” the spokesman said.