REMUS 6000

Figure 1. REMUS 6000

http://mil-embedded.com/articles/unmanned-navys-sea-mine-hunting-capabilities/

A recently deployed Unmanned Systems Maritime Search and Rescue vehicle is the REMUS 6000, (Figure 1.) an unmanned underwater vehicle (UUV) which is an innovative, versatile research tool, designed to operate in depths ranging from 82 feet to 19,685 feet (Woods Hole Oceanographic Institution, 2017).  

The REMUS 6000 played a key role in the search and recovery of the wreckage of Air France Flight 447, an Airbus A33-200, which disappeared over the ocean on June 1, 2009, after encountering severe thunderstorms while enroute to Paris from Rio de Janeiro. In April 2011, a search team lead by Woods Hole Oceanographic Institution, operating three REMUS 6000 autonomous underwater vehicles made by Hydroid, located the plane’s wreckage and black boxes off the coast of Brazil. The discovery was made in nearly 2.5 miles below the Indian Ocean’s surface in topography similar to the Rocky Mountains (Cole, 2014).

The vehicle uses acoustic navigation to independently survey an area, while sensors sample and record data. After data from a large-scale survey is analyzed and smaller field of interest are identified, the REMUS 6000 can gather more detailed, up-close images using high-resolution imaging systems located on the bottom of the vehicle (Woods Hole Oceanographic Institution, 2017).

The inertial navigational unit consists of accelerometers and gyros which measure the vehicle’s movement in three directions and three rotations, which determine the vehicle’s velocity and current mission travel distance. The vehicle uses pulses of sound bounced off of the seafloor to determine its altitude and ground speed, and aids the collision avoidance system in evasive actions to maneuver around an obstacle (Woods Hole Oceanographic Institution, 2017).

The REMUS 6000 also has a 3-way antenna that allows the vehicle, when at the surface, to determine its position using the Global Positioning System (GPS). The antenna also enables the vehicle to “phone home” with its location, if it becomes lost. A custom mounted camera snaps digital photographs when within 10 meters of the seafloor, synced with strobe light. It tags photos and time and stores them in an onboard hard drive, downloadable at the surface (Woods Hole Oceanographic Institution, 2017).

Modifications

Although the REMUS 6000’s dual frequency side-scan sonar helped locate the aircraft wreckage, its maximum operating limit is only 3.7 miles beneath the surface. Consideration for redesigning the REMUS 6000 for increased operating depths should be considered because the limitation required the United States Navy to also deploy a Bluefin-21 vehicle in order to reach the ocean floor, estimated at five miles below the surface (Cole, 2014). Another limitation that can hinder the REMUS 6000 during search and rescue efforts is its endurance, which is only rated at 22 hours (Woods Hole Oceanographic Institution, 2017). Due to long-duration recovery operations, the logistics of having to resurface daily can contribute to delays. Therefore, extending the battery life, or installing a backup battery, would enhance the vehicle’s overall contribution to recovery efforts. 

Unmanned Aerial Systems Interoperability          

The UUV has not only proven beneficial in civilian recovery operations, but in military operations as well. In 2016, during an Annual Naval Technology Exercise, the U.S. Navy successfully launched an unmanned aerial vehicle (UAV), which linked to several UUVs and a submarine control system through a secure digital datalink. The exercise proved that the systems could be successfully linked, while providing real-time information during discreet military operations (Figure 2.) (Howard, 2016).    

Figure 2. U.S. Navy demonstrates AeroVironment's submarine-launched Blackwing™

small UAV that links manned submarines to unmanned undersea vehicles (Howard, 2016).

 (Photo: Business Wire)

Unmanned Systems Advantages

            Unmanned maritime systems present very clear advantages. The major advantage is that it increases the safety factor by decreasing the chances of humans getting hurt during search and rescue operations. Secondly, unmanned systems are able to remain under water for extended periods of time. Another advantage is also during military operations when a UUV can be deployed to detect and identify unknown objects under the sea. The sensor suite that is most effective, especially on UUV, is the dual side sonar, which consists of two arrays of transducers -underwater speaker and microphones, which monitors both sides of the vehicle. The sensor also provides illumination of the seafloor through sound waves, by generating pings which projects a 2D image of objects resting on the seafloor (Woods Hole Oceanographic Institution, 2017).

References

Cole, S. (2014). Unmanned Underwater Vehicles Modernize U.S. Navy’s Sea-Mine-Hunting

Capabilities. Retrieved on 14 July, 2017, from http://mil-

embedded.com/articles/unmanned-navys-sea-mine-hunting-capabilities/

Howard, C. (2016). United States Navy Uses AeroVironment Blackwing UAS for Cross-Domain

Communications, Command, and Control. Retrieved on 14 July, 2017, from http://www.intelligent-aerospace.com/articles/2016/09/united-states-navy-uses-aerovironment-blackwing-uas-for-cross-domain-communications-command-and-control.html

Wood Hole Oceanographic Institution (2017). Remus 6000 – Deep Ocean, Large Area

Search/Survey. Retrieved on 14 July, 2017, from http://www.whoi.edu/main/remus6000