USN has revised its Maritime strategy, for decisive warfighting advantage, in anti-access, area denial environment. US Navy’s vision is to achieve an integrated hybrid force of manned and unmanned systems with the ability to sense, comprehend, predict, communicate, plan, make decisions and take collaborative action to achieve operational goals. The employment of these systems will reduce risk for Sailors and Marines and increase capability.
US Navy vision is for naval platforms that are agile, fuel efficient, flexible and capable of operating cost effectively in varied environments. Enable manned and unmanned naval platforms and forces to seamlessly operate in hostile environments while avoiding, defeating and surviving attacks
Under his strategy, the Navy has taken several new steps in its development of several large underwater drones designed to conduct undersea reconnaissance, share combat essential data with submarine “motherships,” search for and destroy mines and – in some cases – launch attacks on enemy surface and undersea vessels. The Navy has launched Large Displacement Unmanned Underwater Vehicle (LDUUV) program that will design, fabricate, and field a new class of large displacement highly autonomous, Unmanned Undersea Vehicles (UUVs) to provide increased endurance, long range, and payload hosting.
China has also developed large Autonomous Underwater Vehicle. On October 1, 2019, the People’s Republic of China celebrated its 70th birthday in grand fashion, complete with a lavish parade showcasing its growing national power and military might. Among the hypersonic missiles, stealth drones, and other advanced weapons and technologies on display were two somewhat unassuming unmanned undersea vehicles (UUVs) marked “HSU001.” While China has offered sneak peeks into its unmanned undersea R&D efforts before, this marked the first glimpse at a large-scale UUV program designed specifically for covert military operations. While HSU001 lacks the capacity for such large-scale payload integration, it may be capable of deploying micro UUVs or other sensors, or carrying payloads via external hardpoints. While it lacks adequate energy stores to transit thousands of nautical miles like Orca, it will likely be capable of long-endurance missions lasting several weeks to several months.
The Navy in FY2021 and beyond wants to develop and procure three types of large unmanned vehicles (UVs). These large UVs are called Large Unmanned Surface Vehicles (LUSVs), Medium Unmanned Surface Vehicles (MUSVs), and Extra-Large Unmanned Undersea Vehicles (XLUUVs). The Navy wants to acquire these large UVs as part of an effort to shift the Navy to a more distributed fleet architecture. Compared to the current fleet architecture, this more distributed architecture is to include proportionately fewer large surface combatants (i.e., cruisers and destroyers), proportionately more small surface combatants (i.e., frigates and Littoral Combat Ships), and the addition of significant numbers of large UVs.
The US Defense Advanced Research Projects Agency (DARPA) launched a programme in 2019 designed to develop a new class of future unmanned underwater vehicles (UUVs) that are capable of both long duration missions and large payload capacity. The current UUV designs, are constrained to allow either large payload capacity or long endurance missions.
“Today’s payload-capable UUV operations are generally limited to shorter duration missions due to propeller‐driven propulsion powering requirements and a fixed battery capacity,” it said, adding that energy capacity limitations “typically couple existing UUVs to manned host platforms, larger UUVs, or ports for periodic recharging”.
In Sep 2021, Chinese researchers also tested a new undersea drone shaped like a manta ray, in what appears to be its first open water test in the South China Sea. Utilizing a type of bio-inspired design, the drone—created by a university with strong ties to the Chinese military—uses the manta ray’s shape to help it efficiently glide through the water.
The unnamed UUV is modeled on the “shape and motion” of a manta ray, and can “flap its wings and slide underwater” like a real ray, per Xinhua. It explains that the rays are the ocean’s “most efficient swimmers,” and are known for “high propulsion efficiency, high mobility and stability, low noise and large load capacity.”
Manta Ray program
The next-generation UUV, known as the Manta Ray, is intended to provide operational commanders with expanded capacities without disrupting current operations by remaining independent of manned vessels and ports once deployed. UUVs that operate for extended durations without the need for on-site human logistics support or maintenance offer the potential for persistent operations during longer term deployments. And they could be acquired and supported at a significantly reduced cost compared to current UUV types.
A secondary goal of the program is to advance key technologies that will benefit other naval designs such as low lifecycle cost UUV operations, long duration undersea energy management techniques, biofouling reduction technologies, and long duration navigational enablers. According to DARPA, specific capability areas of interest include novel energy management techniques for UUV operations, innovative low‐power means of underwater threat detection and classification, and mission management approaches for extended durations while accounting for dynamic maritime environments.
According to DARPA, the Manta Ray programme plans to advance key technologies – up to and including at-sea demonstrations – that will benefit future UUV designs. Among the technical themes highlighted by DARPA are low‐power, high efficiency undersea propulsion systems, undersea energy harvesting techniques (at operationally relevant depths), new approaches to mitigate biofouling, corrosion, and other material degradation during long duration missions, and innovative means to leverage existing maritime data and exploit novel maritime data for high‐efficiency navigation and/or communications. These also include novel energy management techniques for UUV operations; low-power, high-efficiency propulsion systems; innovative low-power techniques for underwater detection and classification of hazards, and counter-detection of threats.
“The Manta Ray program aims to increase at-sea operational capacity and capabilities for the combatant commander while minimizing disruptions to current operations by remaining independent of crewed vessels and ports once deployed,” said CDR Kyle Woerner, the Manta Ray program manager in DARPA’s Tactical Technology Office. “If successful, this new class of UUVs would allow operational flexibility and relief of workload for both traditional host ships and servicing ports.”
Manta Ray Awards
Manta Ray is a multi-phase effort that includes at-sea demonstration of critical technologies. The program is using a disciplined systems engineering approach to define demonstration system objectives and identify enabling technologies needed for future systems.
DARPA’s Manta Ray Program aims to demonstrate critical technologies for a new class of long duration, long range, payload-capable unmanned underwater vehicles (UUVs). UUVs that operate for extended durations without the need for on-site human logistics support or maintenance offer the potential for persistent operations during longer term deployments.
DARPA has selected three companies to focus on development of an integrated solution for Manta Ray technology and operational areas. They are:
- Lockheed Martin Advanced Technology Laboratories
- Northrop Grumman Systems Corporation
- Navatek, LLC
A fourth company, Metron, Inc., will work toward critical technology and solutions specific to the field of undersea energy harvesting techniques at depths necessary for successful operations.
In Feb 2021,It was reported that Defense Advanced Research Projects Agency (DARPA) has selected three prime contractors for an unmanned underwater vehicle (UUV) development programme. The selected contractors for the Manta Ray project include Northrop Grumman Systems, Martin Defense Group, (formerly Navatek) and Metron. The preliminary design reviews were completed earlier in 2021 year.
The Manta Ray program plans to advance key technologies that will benefit future UUV designs, including, but not limited to new energy management and energy harvesting techniques at operationally relevant depths; low-power, high-efficiency propulsion; and new approaches to mitigate biofouling, corrosion, and other material degradation for long duration missions. The program also seeks process improvements, including mission management approaches for extended durations while accounting for dynamic maritime environments; unique methods for leveraging existing maritime datasets and new maritime parameters for high-efficiency navigation; and new low-power means of underwater detection and classification of hazards.
In Sep 2021, Martin Defense Group was awarded a $54.8 million contract to develop control software and energy harvesting module for the Defense Advanced Research Projects Agency’s long-range unmanned underwater vessel. The effort is under the second developmental phase of DARPA’s Manta Ray UUV program and the Honolulu, Hawaii-based small business is expected to complete the software and module by August 2024, the Department of Defense said Wednesday. The aim is to develop an energy-harvesting system to power it indefinitely, allowing the robot sub to carry out missions lasting months or years without returning to base or refueling.
Manta Ray is targeting three phases of development, culminating with a fully integrated demonstration vehicle completing an underwater mission in a dynamic, open-ocean environment.
DARPA launches Phase Two of Manta Ray UUV maritime drone project in Dec 2021
DARPA originally launched the Manta Ray UUV project in 2020, but in Dec 2021 it said it had signed deals with two defense companies to continue work on the aquatic drone. Teams from Northrop Grumman Systems Corporation and Martin Defense Group will work to develop full-scale demonstration versions of what until now have been conceptual and schematic computer-generated simulations.
DARPA says Phase One of the Manta Ray program concluded with critical reviews that demonstrated conceptual and design viability, and the project’s overall readiness to proceed to the next development stage. As it does, Martin Defense and Northrop Grumman will work first on subsystem testing, followed by production and submarine demonstrations of completed UUVs – presumably something not dissimilar, in generally fishy security terms, to the Robo-Shark drone China unveiled this year.
By the end of Phase Two, the two contracting groups are expected to exhibit the operational capacities of the Manta Ray UUVs, whose main function will be to perform long-distance and -endurance aquatic missions. Being a national defense innovation unit as it is, DARPA has declined to offer a plethora of detail on the future maritime drone, other than to say its tech will allow for payload-capable autonomous ocean sorties.
A YouTube video DARPA uploaded titled “Manta Ray – Breaking the UUV mold” offers a tad more insight into what the UUV may be used for. As it cruises the ocean, the triangular vehicle stabilizes itself to allow a second drone to pop out of its back for apparent data collection and surveillance work. The smaller craft is tethered, presumably to facilitate transfer and storage of information in the host UUV, in which the mini-craft re-docks before the pair moves silently on.