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Common Unmanned Underwater Vehicle (UUV) Stern Launch and Recovery System

Description:

TECHNOLOGY AREA(S): Ground Sea 

OBJECTIVE: Develop a launch and recovery system that can accommodate a variety of sizes of Unmanned Underwater Vehicles (UUVs) when installed aboard LCS ships. 

DESCRIPTION: The Navy is looking for a common solution to launch and recover a variety of UUVs from large to small, and that can operate from near the waterline (Freedom variant Littoral Combat Ship (LCS)) to high above the waterline (Independence variant LCS). The Navy needs a system for launching and recovering UUVs that are of a variety of sizes, weights, and shapes from a variety of ship platforms and waterline heights. UUVs are off-board vehicles that are typically cylindrical or semi-cylindrical in cross section and can range in size from a small, hand-launched system such as the Woods Hole Oceanographic Institute (WHOI) REMUS 100 to large systems such as the HUGIN 3000 and REMUS 6000. UUVs can be designed to be free-flooding or hermetically sealed, but often their shells are not adequate for lifting or grappling purposes. They often have easily damaged external features such as fins, propulsors, propellers, and antennas. Different manufacturers design different features for lifting including nose lift, tail lift, single-point body lift, and two-point body lift. Many UUVs are not designed to be driven or piloted through the water; they operate on a point-to-point system, diving underwater to transit via Inertial Navigation System (INS)/Inertial Measuring Unit (IMU) to a location where they surface to acquire the Global Positioning System (GPS) for a location fix. Many UUVs are equipped with forward looking or bottom mapping sonars that make interfacing with these areas difficult. Current commercial launch and recovery systems are often ship specific and UUV/AUV specific. Institutions such as WHOI and private industries supporting the petroleum industry all use UUVs/Autonomous Underwater Vehicles (AUVs) and conduct numerous launch and recovery operations every year. Pier-side launch and recovery of UUVs is relatively simple as large cranes or davits can be used to lower or recover UUVs in sheltered bays, inlets, waterways. There is often unlimited overhead and the launch/recovery system is not in motion. With underway launch and recovery aboard a ship, the ship may be transiting to maintain heading and minimize ship motions. The ship may be hovering to allow the UUV to be lowered or lifted from a fixed location. The ship may be stationary but not hovering, in which case the ship will be driven by wind and waves, often causing the ship to heave, roll, sway, and yaw. The launch and recovery system will likewise be in motion at the same time the UUV will be in motion, often with a different frequency, phase, and magnitude. The UUV will not necessarily be aligned to the same heading as the ship, or be able to be commanded to do so. Many UUVs do not have tow points allowing them to be put undertow by the ship for launch or recovery. The goal of this design is to provide flexibility of capability and interfaces that will support a variety of UUVs (in various sea states). This should take into consideration the design constraints associated with UUVs such as easily damaged components (e.g., fins, propellers/propulsors, external antennas), hull/shell strength, hard points/lift points, and UUVs that cannot be driven/piloted like a boat (i.e., they only operate by underwater movement from GPS coordinate to GPS coordinate). The Navy has an objective to launch and recover UUVs in sea states through sea state 3 in accordance with STANAG 4194:1983. Supported platforms potentially could have a freeboard anywhere from near the waterline to as high as 15’ above the waterline. Both variants of the LCS as well as the Expeditionary Fast Transport (EPF) ship utilize stern launch and recovery of watercraft, versus using a moon pool or side mounted launch and recovery system. A common approach to stern launch a UUV from a ship is to bring the ship to a standstill, deploy the handling system and lower the UUV to the water’s edge before releasing it. Depending upon whether the UUV is suspended or captive, a towline can be rigged to ensure the UUV maintains a suitable orientation relative to the ship and to the horizon. Once the UUV is clear of the ship, it can begin its functional mission. Other methods include slowing the ship to a minimal speed at which steerage can be maintained, and towing the UUV as it enters the water. The current process to recover a UUV depends upon the approach. Web page searches will show multiple approaches from underbelly lift for small UUVs (REMUS 100), nose tow up a ramp (HUGIN 3000), and vertical recovery (REMUS 6000) using an A-frame stern launch and recovery system. WHOI developed a Launch and Recovery System (LARS) specific to the REMUS 6000. From information available on the WHOI website: “The REMUS Launch and Recovery System has made over 1,000 successful launch and recoveries to date. Due to the vehicle's larger size, this self-contained system has been engineered here at WHOI in the OSL. It enables the L & R of the vehicle in sea states up to those created by the Beaufort Scale 5 winds. It requires only one operator and, therefore, does away with the need to use tag lines eliminating extra people on deck and creating a safer working environment. LARS is installed on the stern of a ship. For launch, the LARS has a built-in A-frame, which tilts the cradle up and over, while leaving the vehicle hanging by its nose well clear of the fantail. The cradle supports the vehicle during A-frame rotation, stabilizing the vehicle until it is a safe distance from the stern. The docking head provides damping to reduce swing in heavy seas. The vehicle is then lowered into the water, tail first, while the ship is making approximately 1-2 knots forward way (this allows the vehicle to stay well clear of the ships screws). All systems are given one final checkout before release. When ready, the vehicle is commanded to release its tow-line and begin its mission.” Likewise, from the same website, the LARS for the REMUS 3000 is described as follows: “The REMUS 3000 Launch and Recovery system, similar to the proven system of our REMUS-6000 which has completed over 1,000 successful launch and recoveries to date, has a footprint of 5.5' x 10'. The control consists of a tilt A-frame, tilt docking head, pay in/out winch and rotate vehicle. This system enables the launch and recovery system of the AUV to be simple, reliable, easy to operate and time-saving with the hydraulics operating at 10-15 HP with a built-in joystick controls in a waterproof operator console. The system is vessel dependent and is mounted on the stern of a ship. It allows the vehicle to be operated from a vessel in sea states up to those generated by the Beaufort Scale 5 winds.” The HUGIN 1000 can be installed in a 20-foot ISO container, which is used for storage, maintenance, launch, and recovery. According to the Kongsberg website, the HUGIN 1000 and launch device (stern ramp) can be deployed from the 20-foot ISO container from the stern of a ship. Typically, the largest challenge is to align the ship to a stationary UUV, secure a suitable lifting or towing apparatus to the UUV, and then lifting or towing the UUV from the water. Since UUVs can roll, approaches such as a v-shaped ramp or underbelly netting are generally not going to be acceptable approaches to lifting a wide range of UUVs because so many cannot afford to roll over or have fins/propellers take strain from lifting systems. Lifecycle costs will be reduced by having a single ship that can perform multiple functions/missions with UUVs, all while using a single LARS. Likewise, savings can be realized in the use of a common LARS across various ship and shore platforms. Cost savings can be realized through reduced need for spares/use of common spares; standardized technical support services and manuals; savings through larger purchase quantities; commonality of materials and fluids. Additionally, a common handling system can be used as design criteria for future UUVs allowing them to integrate to a single system, versus developing a unique approach for every new UUV before the Navy or other users have an opportunity to influence interfaces and design. Proposers need to mindful that, if applicable, the development of supporting software must be done in an open architecture environment to facilitate maximum compatibility with future system iterations. 

PHASE I: Define and develop a concept for both launch and recovery of UUVs of various sizes as defined in the description. Investigate innovative solutions to meet shipboard operational environments, interface with a variety of UUVs, and establish that the solutions can be feasibly developed into useful products for the Navy. Establish feasibility by analytical modeling and simulation to provide an initial assessment of their concept performance. Provide a final report as a deliverable documenting their design and design constraints and describing both the envisioned approach for installing the proposed system on both a ship with low deck (near the waterline) and one with a high deck (at least 15 feet above the waterline) and the essential characteristics of the system supported by feasibility simulations of launch and recovery. The Phase I Option would include the initial layout and capabilities description to build the unit in Phase II. Provide a Phase II Initial Proposal as a deliverable. 

PHASE II: Based on the results of Phase I and the Phase II Statement of Work (SOW), develop a prototype for evaluation and delivery. Test the key software and hardware components of the prototype initially in a lab and then pier-side. After the integration of any refinements required, the Navy will evaluate the prototype to determine its capability to meet the performance goals defined in the Phase II SOW and the Navy requirements for the launch and recovery of UUVs in various sea states. Support Navy demonstration and evaluation of the system performance through prototype testing and evaluation on a representative ship or ships (to meet both waterline requirements) with UUVs or UUV simulators (i.e., floating shapes intended to represent actual UUVs) over the required range of parameters. Testing will include numerous deployment cycles to demonstrate repeatability. Use the evaluation results to refine the prototype into a design for a first-order production unit that will meet Navy requirements. Prepare a Phase III development plan to transition the technology to Navy use. 

PHASE III: Support the Navy in transitioning the technology for Navy use. Produce a developmental model, and integration plan for the launch and recovery of UUVs as a modular system that can be installed on a variety of LCS ship platforms. Support the Navy for test and validation to certify and qualify the system for Navy use. A lucrative market currently exists for at-sea launch and recovery of Autonomous/Underwater Unmanned Vehicles. Current commercial launch and recovery systems are often ship-specific and UUV/AUV-specific. Institutions such as WHOI and private industries supporting the petroleum industry all use UUVs/AUVs and conduct numerous launch and recovery operations every year. The ability to operate multiple systems from a common platform is seen as an advantage since it affords the operators flexibility of both ship design and AUV/UUV capability. 

REFERENCES: 

1: "REMUS 100." Woods Hole Oceanographic Institution website, http://www.whoi.edu/main/remus100

2:  "HUGIN AUV Launch & Recovery System." YouTube. KONGSBERG Gruppen, 16 November 2011. https://www.youtube.com/watch?v=-H5uZWv22Ws

3:  "REMUS 6000." Woods Hole Oceanographic Institution website. http://www.whoi.edu/main/remus6000

4:  "STANAG 4194:1983 Standardized Wave and Wind Environments And Shipboard Reporting Of Sea Conditions." SAI Global, 2017. http://infostore.saiglobal.com/store/details.aspx?ProductID=456675

KEYWORDS: Shipboard Launch And Recovery Of UUVs; Unmanned Underwater Vehicles; Off-board Vehicles; Autonomous Underwater Vehicles; Handling System; REMUS 

CONTACT(S): 

Darryl Updegrove 

(850) 235-5142 

darryl.updegrove@navy.mil 

Ms. Samantha Smith 

(850) 230-7966 

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