DARPA has announced that it has successfully completed its Anti-Submarine Warfare (ASW) Continuous Trail Unmanned Vessel (ACTUV) program.

The technology demonstration vessel, christened Sea Hunter, has officially been transferred to the Office of Naval Research (ONR). ONR will continue developing the vehicle, which is described as “the first of what could ultimately become an entirely new class of ocean-going vessel able to traverse thousands of kilometers over open seas for months at a time, without a single crew member aboard—as the Medium Displacement Unmanned Surface Vehicle (MDUSV).”

“ACTUV’s move from DARPA to ONR marks a significant milestone in developing large-scale USV technology and autonomy capabilities,” says Alexander Walan, a program manager in DARPA’s Tactical Technology Office (TTO).

“Our collaboration with ONR has brought closer to reality a future fleet in which both manned warships and capable large unmanned vessels complement each other to accomplish diverse, evolving missions.”

Robert Brizzolara, ONR program officer for MDUSV, says, “ONR appreciates the truly impressive work by DARPA in advancing this technology, and the strong partnership we've had on ACTUV over the years. As ACTUV transfers from DARPA to ONR, ONR is looking forward to continuing and capitalizing on the science and technology work.”

The collaboration between DARPA and ONR began back in September 2014, when the agencies agreed to jointly fund an extended test phase of an ACTUV prototype. A christening ceremony in April 2016 marked the vessel’s formal transition from a DARPA-led design and construction project to a new stage of open-water testing conducted jointly with ONR in San Diego, California.

DARPA and ONR began at-sea testing Sea Hunter’s sensing and autonomy suites in October 2016. Between February and September of last year, Sea Hunter passed three progressively challenging tests to integrate the suites and use them to comply with International Regulations for Preventing Collisions at Sea (COLREGS) in “operationally realistic scenarios.”

DARPA and ONR also performed tests to prove the “flexibility to handle diverse missions by switching among modular payloads,” which is considered a key element of the ACTUV/MDUSV design. In September 2016, Sea Hunter had a successful joint test with DARPA’s Towed Airborne Lift of Naval Systems (TALONS) research effort. In August 2017, Sea Hunter conducted at-sea tests with a mine countermeasures (MCM) payload.

ONR plans more at-sea tests to continue the development of ACTUV/MDUSV technologies, including “automating payload and sensor data processing, rapidly developing new mission-specific autonomous behaviors, and exploring autonomous coordination among multiple USVs.” MDUSV could transition to U.S. Navy operations at some point this year, depending on test results.