Drones very small to large
Thursday, February 7, 2013
Drones very small to large
I was looking at the Time magazine article on drones from hummingbird size to really large ones. The first four I will share have only cameras on board and so are non-lethal and only used to gather visual and sometimes sound information wherever they go. The second 4 (3 for air and 1 for sea use) are military grade and potentially lethal. Actually, I find the humminbird in some ways the most disturbing because you actually might mistake it for a real hummingbird while having an important conversation regarding business or private information that you really don't want the whole world to know because it is your personal private information after all and you do have the right of privacy. However, as far as I know this is a U.S. Government intelligence tool and not for private use at present.
begin quote from wikipedia under the heading "nano air vehicle"
AeroVironment Nano Hummingbird
From Wikipedia, the free encyclopedia
|Artificial hummingbird weighs less than an AA battery|
SpecificationsDARPA contributed $4 million to AeroVironment since 2006 to create a prototype "hummingbird-like" aircraft for the Nano Air Vehicle (NAV) program. The result was called the Nano Hummingbird which can fly at 11 miles per hour (18 km/h) and move in three axes of motion. The aircraft can climb and descend vertically; fly sideways left and right; forward and backward; rotate clockwise and counter-clockwise; and hover in mid-air. The artificial hummingbird maneuver using its flapping wings for propulsion and attitude control. It has a body shaped like a real hummingbird, a wingspan of 6.3 inches (160 mm), and a total flying weight of 0.67 ounces (19 g)—less than an AA battery. This includes the systems required for flight: batteries, motors, and communications systems; as well as the video camera payload.
Technical goalsDARPA established flight test milestones for the Hummingbird to achieve and the finished prototype met all of them, and even exceeded some of these objectives:
- Artificial hummingbird developed Irish Independent. 2011-02-18.
- Nano Hummingbird. AeroVironment, Inc. 2011-02-16.
- AeroVironment Develops World’s First Fully Operational Life-Size Hummingbird-Like Unmanned Aircraft for DARPA. AeroVironment, Inc. 2011-02-16.
- It's a bird! It's a spy! It's both Los Angeles Times, 2011-02-17.
- Nano Air Vehicle Defense Sciences Office, DARPA. Retrieved: 2011-02-20.
- Press release
- Videos of the Nano Hummingbird in action
- DARPA Nano Air Vehicle web page[dead link]
- DARPA Nano Air Vehicle Program: Fact Sheet[dead li
- End quote from:
- wikipedia under the heading "Nano Air Vehicle"
- Note: Still working on getting info on the other 7 types of drones.
- Here next is the Wikipedia site on Quadrotors. At first I wanted just the A.R. Drone which is the most bought one by hobbyists likely at present around the world that can be operated by a smart phone or Ipad or other device like that. I believe it streams real time video footage looking straight down below it as it flies which likely can be captured on your smartphone or other device or sent to your laptop to put online or to store for private use.
QuadrotorFrom Wikipedia, the free encyclopedia
Quadrotor De Bothezat Quadrotor, 1923.
Early in the history of flight, quadrotor configurations were seen as a possible solution to some of the persistent problems in vertical flight; torque-induced control issues (as well as efficiency issues originating from the tail rotor, which generates no useful lift) can be eliminated by counter-rotation and the relatively short blades are much easier to construct. A number of manned designs appeared in the 1920s and 1930s. These vehicles were among the first successful heavier-than-air vertical take off and landing (VTOL) vehicles. However, early prototypes suffered from poor performance, and latter prototypes required too much pilot work load, due to poor stability augmentation and limited control authority.
More recently quadrotor designs have become popular in unmanned aerial vehicle (UAV) research. These vehicles use an electronic control system and electronic sensors to stabilize the aircraft. With their small size and agile maneuverability, these quadrotors can be flown indoors as well as outdoors.
 Second, the use of four rotors allows each individual rotor to have a smaller diameter than the equivalent helicopter rotor, allowing them to possess less kinetic energy during flight. This reduces the damage caused should the rotors hit anything. For small-scale UAVs, this makes the vehicles safer for close interaction. Some small-scale quadrotors have frames that enclose the rotors, permitting flights through more challenging environments, with lower risk of damaging the vehicle or its surroundings.
Due to their ease of both construction and control, quadrotor aircraft are frequently used as amateur model aircraft projects.
Flight controlthrust and torque about its center of rotation, as well as a drag force opposite to the vehicle's direction of flight. If all rotors are spinning at the same angular velocity, with rotors one and three rotating clockwise and rotors two and four counterclockwise, the net aerodynamic torque, and hence the angular acceleration about the yaw axis is exactly zero, which implies that the yaw stabilizing rotor of conventional helicopters is not needed. Yaw is induced by mismatching the balance in aerodynamic torques (i.e., by offsetting the cumulative thrust commands between the counter-rotating blade pairs).
Angular accelerations about the pitch and roll axes can be caused separately without affecting the yaw axis. Each pair of blades rotating in the same direction controls one axis, either roll or pitch, and increasing thrust for one rotor while decreasing thrust for the other will maintain the torque balance needed for yaw stability and induce a net torque about the roll or pitch axes. This way, fixed rotor blades can be made to maneuver the quad rotor vehicle in all dimensions. Translational acceleration is achieved by maintaining a non-zero pitch or roll angle.
- Oehmichen No.2, 1920
Etienne Oehmichen experimented with rotorcraft designs in the 1920s. Among the six designs he tried, his helicopter No.2 had four rotors and eight propellers, all driven by a single engine. The Oehmichen No.2 used a steel-tube frame, with two-bladed rotors at the ends of the four arms. The angle of these blades could be varied by warping. Five of the propellers, spinning in the horizontal plane, stabilized the machine laterally. Another propeller was mounted at the nose for steering. The remaining pair of propellers were for forward propulsion. The aircraft exhibited a considerable degree of stability and controllability for its time, and made more than a thousand test flights during the middle 1920s. By 1923 it was able to remain airborne for several minutes at a time, and on April 14, 1924 it established the first-ever FAI distance record for helicopters of 360 m (390 yd). Later, it completed the first 1 kilometre (0.62 mi) closed-circuit flight by a rotorcraft.
- de Bothezat quadrator, 1922
Dr. George de Bothezat and Ivan Jerome developed this aircraft, with six bladed rotors at the end of an X-shaped structure. Two small propellers with variable pitch were used for thrust and yaw control. The vehicle used collective pitch control. It made its first flight in October 1922. About 100 flights were made by the end of 1923. The highest it ever reached was about 5 m (16 ft 5 in). Although demonstrating feasibility, it was, underpowered, unresponsive, mechanically complex and susceptible to reliability problems. Pilot workload was too high during hover to attempt lateral motion.
- This unique helicopter was intended to be the prototype for a line of much larger civil and military quadrotor helicopters. The design featured two engines driving four rotors with wings added for additional lift in forward flight. No tailrotor was needed and control was obtained by varying the thrust between rotors. Flown successfully many times in the mid 1950s, this helicopter proved the quadrotor design and it was also the first four-rotor helicopter to demonstrate successful forward flight. Due to a lack of orders for commercial or military versions however, the project was terminated.
- Convertawings proposed a Model E that would have a maximum weight of 42,000 lb (19,000 kg) with a payload of 10,900 lb (4,900 kg).
- Curtiss-Wright VZ-7, 1958
- The Curtiss-Wright VZ-7 was a VTOL aircraft designed by the Curtiss-Wright company for the US Army. The VZ-7 was controlled by changing the thrust of each of the four propellers.
Bell Boeing Quad TiltRotorThe Bell Boeing Quad TiltRotor concept takes the fixed quadrotor concept further by combining it with the tilt rotor concept for a proposed C-130 sized military transport.
OtherSmall quadrotor aircraft are also produced commercially and for military roles such as observation.
- Aermatica Spa's Anteos is the first rotary wing RPA (remotely piloted aircraft) to have obtained official permission to fly (Permit To Fly) issued in the civil airspace, by the Italian Civil Aviation Authority (ENAC), and will be the first able to work in non segregated airspace.
- AeroQuad is an open-source hardware and software project which utilises Arduino boards and freely provides hardware designs and software for the DIY construction of Quadrocopters.
- ArduCopter is an open-source multicopter UAV. Based on Arduino, it supports from four to eight motors, as well as traditional helicopters, and allows fully autonomous missions as well as RC control. 
- OpenPilot is a model aircraft open-source software project.
- Parrot AR.Drone is a small radio controlled quadrocopter with cameras attached to it built by Parrot SA, designed to be controllable with iOS or Android devices. Parrot AR.Drone 2.0 carries a HD 720P camera and more sensors, such as altimeter and magnetometer.
- Leishman, J.G. (2000). Principles of Helicopter Aerodynamics. New York, NY: Cambridge University Press.
- Anderson, S.B. (March). "Historical Overview of V/STOL Aircraft Technology". NASA Technical Memorandum 81280
- Hoffmann, G.M.; Rajnarayan, D.G., Waslander, S.L., Dostal, D., Jang, J.S., and Tomlin, C.J. (November 2004). "The Stanford Testbed of Autonomous Rotorcraft for Multi Agent Control (STARMAC)". In the Proceedings of the 23rd Digital Avionics System Conference. Salt Lake City, UT. pp. 12.E.4/1-10.
- Büchi, Roland (2011). Fascination Quadrocopter. ISBN 978-3-8423-6731-9.
- Pounds, P.; Mahony, R., Corke, P. (December 2006). "Modelling and Control of a Quad-Rotor Robot". In the Proceedings of the Australasian Conference on Robotics and Automation. Auckland, New Zealand.
- Hoffman, G.; Huang, H., Waslander, S.L., Tomlin, C.J. (20–23 August 2007). "Quadrotor Helicopter Flight Dynamics and Control: Theory and Experiment". In the Conference of the American Institute of Aeronautics and Astronautics. Hilton Head, South Carolina.
- Arduino-based quadcopter
- UAVP-NG based quadcopter
- "Oemichen helicopter - development history, photos, technical data".
- "De Bothezat - development history, photos, technical data".
- "Helicopters of the World" Flight 2 November 1956 p722]
- Microdrones: commercial quadrotors[dead link]
- Datron Scout military quadrotor model aircraft
- "Products". Aermatica. Retrieved 2012-05-30.
- Davies, Chris (13 January 2010). "DIY Quadrocopters: Quaduino NG and AeroQuad [Videos"]. SlashGear. Retrieved 4 February 2012.
- "ArduCopter 3D Robotics Quadcopter". Retrieved May 24, 2012.
- "Open Pilot CopterControl Board". Retrieved March 22, 2012.
end quote from Wikipedia under the Heading "Quadrotor".
I couldn't find a page yet at Wikipedia regarding the Draganflyer X6 so I have to quote directly from it's actual page.
Applications at a GlanceAll Applications
IndustrialWhether you are in the business of constructing, managing, selling, promoting, or inspecting, the addition of aerial photography and/or videography can enhance your business.
GovernmentBe it resources, law, transportation, fire, emergency measures, all can benefit from aerial observation and recordings to assist with management and enforcement issues.
EducationAdvance research in various fields such as advanced UAV flight and robotics. Acquire aerial photography and video for research on natural resources, geology and archeology.
Features at a GlanceAll Features
- Six Rotor Configuration The 6-rotor design provides double the thrust while leaving a smaller footprint than our equivalent sized 4-rotor helicopters. Able to tolerate loss of 1 engine... and land. More Info
- GPS Fly into position, flick a switch, and maintain position without any control input - operate hands-free. Able to ascend and descend within in a vertical column. More Info
- Anti-Vibration Camera Mount Designed specifically for the characteristics of the digital still, HD video, FLIR and low light B/W all with 90° remote controlled tilt. More Info
Draganflyer X6 Overview
What is the Draganflyer X6?The Draganflyer X6 is a remotely operated, unmanned, miniature helicopter designed to carry wireless video cameras and still cameras. Operate the Draganflyer X6 helicopter with the easy to use handheld controller while viewing what the helicopter sees through video glasses. The Draganflyer X6 helicopter uses a unique 6-rotor design refined from an original concept that has been under development since early 2006. Draganflyer X6 Tech Specs
ExpandableThe Draganflyer X6 helicopter accepts multiple interchangeable video camera and still camera modules.
Choose the camera that is best for you:
- 14.1 MP digital still camera with 1080p video recording
- Thermal imaging video camera
What can it do for you?Use the high definition motion video provided by the Draganflyer X6 helicopter for security, reconnaissance, inspection, damage assessment, research, real estate promotion, or advertising. It can be used for virtually anything. Draganflyer X6 Applications
Easy to FlyThe Draganflyer X6 helicopter uses 11 sensors and thousands of lines of code to self-stabilize during flight. This means the Draganflyer X6 is easier to fly than any other helicopter in its class. The Draganflyer X6 on-board software is the result of extensive testing and development since early 2006. Draganflyer X6 Flight Stability
ReliableWith no unnecessary moving parts, the Draganflyer X6 helicopter will operate without maintenance many times longer than conventional helicopters. The motors directly drive the rotors; there are no gears to wear out. Draganflyer X6 Advanced Power System
Grant AssistanceThe Department of Homeland Security makes grants available to states, local and tribal jurisdictions, and other regional authorities to assist in planning, equipment purchase, training, and exercise needs. Draganfly Innovations will provide grant writing support, consultation, and assistance to qualified agencies.
- Contact Kevin, our grant assistance specialist,
Call 1-800-979-9794 or 306-955-9907 (ext. 6111)
AffordableThe Draganflyer X6 provides many of the same benefits of larger surveillance aircraft at a fraction of the cost. Obtain aerial photography without the cost of having to rent a plane each time! Request a Quote
UAV Tactical UseThe Draganflyer X6 helicopter is a revolutionary reconnaissance Unmanned Aerial Vehicle (UAV); it can be transported in a lightweight softshell pack with a military grade backpack while always being ready for flight in minutes. Fly it over hills to get a safe view of what is on the other side. Draganflyer X6 Military Applications
end quote from: http://www.draganfly.com/uav-helicopter/draganflyer-x6/
Here is the Raven Drone a Military Grade Intelligence gathering smaller Drone: Begin quote from Wikipedia under the heading "Raven Drone"
AeroVironment RQ-11 Raven
From Wikipedia, the free encyclopedia
|RQ-11 Raven UAV|
|Army Cpl. Jerry Rogers assembles an RQ-11 Raven unmanned aerial vehicle (in Taji, Iraq)|
|Role||Remote controlled UAV|
|First flight||October 2001|
|Status||In use on combat field|
|Primary users||United States Army
United States Air Force, United States Marine Corps, United States Special Forces, international land forces
|Number built||19,000+ airframes|
|Developed from||FQM-151 Pointer|
The RQ-11 Raven was originally introduced as the FQM-151 in 1999, but in 2002 developed into its current form, resembling an enlarged FAI class F1C free flight model aircraft in general appearance. The craft is launched by hand and powered by a pusher configuration electric motor. The plane can fly up to 6.2 miles (10.0 km) at altitudes of appx 500 feet (150 m) above ground level (AGL), and over 15,000 feet (4,600 m) above mean sea level (MSL), at flying speeds of 28-60 mph (45–97 km/h).
Design and developmentThe Raven RQ-11B UAV system is manufactured by AeroVironment. It was the winner of the US Army's SUAV program in 2005, and went into Full-Rate Production (FRP) in 2006. Shortly afterwards, it was also adopted by USSOCOM, the US Marines, and the US Air Force for their ongoing FPASS Program. It has also been adopted by the military forces of many other countries (see below). More than 19,000 Raven airframes have been delivered to customers worldwide to date. A new Digital Data Link-enabled version of Raven now in production for US Forces and allies has improved endurance, among many other improvements.
The Raven can be either remotely controlled from the ground station or fly completely autonomous missions using GPS waypoint navigation. The UAV can be ordered to immediately return to its launch point simply by pressing a single command button. Standard mission payloads include CCD color video cameras and an infrared night vision camera.
The RQ-11B Raven UAV weighs about 1.9 kg (4.2 lb), has a flight endurance of 60–90 minutes and an effective operational radius of approximately 10 km (6.2 miles).
The RQ-11B Raven UAV is launched by hand, thrown into the air like a free flight model airplane. The Raven lands itself by auto-piloting to a pre-defined landing point and then performing a 45° slope (1 foot down for every 1 foot forward) controlled "Autoland" descent. The UAV can provide day or night aerial intelligence, surveillance, target acquisition, and reconnaissance.
- RQ-11A Raven A (no longer in production)
- RQ-11B Raven B
- RQ-11B eight channel
- RQ-11B DDL (Digital Data Link)
- Solar Raven - In November 2012, the Air Force Research Laboratory integrated lightweight, flexible, high-efficiency solar panels into the Raven platform. The additional power from the solar panels increased the Raven's endurance by 60%. The solar cells were successfully integrated onto the removable wing sections of the UAV. They are 20 square centimeters in size and adhere to the wings of the vehicle using a clear, protective plastic film and an adhesive. The cells were integrated into the existing power system to augment the lithium ion battery. Future improvements include improving the durability of the solar panels and reducing their weight. Integration work is also being conducted on the AeroVironment Wasp and the RQ-20 Puma.
OperatorsUnited States Army, Air Force, Marine Corps, and Special Operations Command. Additionally, foreign customers include Australia, Estonia, Italy, Denmark, Spain and Czech Republic. As of early 2012, over 19,000 airframes have already been shipped, making it the most widely adopted UAV system in the world today.
The British forces in Iraq are using U.S. Raven equipment and personnel on loan. The Royal Danish Army acquired 12 Raven systems in September 2007 - three systems will be delivered to the Huntsmen Corps, while the remainder will be deployed with soldiers from the Artillery Training Center. A 2010 documentary film, Armadillo, shows Danish forces deploying a Raven in operations around FOB Armadillo in the Helmand province of Afghanistan.
The Netherlands MoD has acquired 72 operational RQ-11B systems with a total value of $23.74 million for use within Army reconnaissance units, its Marine Corps and its Special Forces (KCT). At the turn of the year 2009 to 2010 the systems were deployed above the village Veen, as part of the Intensification of Civil-Military Cooperation. In 2012 and 2013 the Raven was loaned by the Defense department to the police department of Almere to combat burglary. 
In April 2011, the U.S. announced that it would be supplying 85 Raven B systems to the Pakistan Army.
In June 2011, the U.S. announced $145.4 million in proposed aid for anti-terror efforts in north and east Africa, including four Raven systems to be used by forces from Uganda and Burundi as part of the ongoing African Union peacekeeping mission in Somalia.
Capture by Iran
|This section's factual accuracy is disputed. (February 2013)|
- Wing Span 55in (130 cm)
- Length 36in (109 cm)
- Weight 4.2 lb (1.9 kg)
- Engine Aveox 27/26/7-AV electric motor
- Cruising speed approx. 30 kn (56 km/h)
- Range 6.2 miles (10 km)
- Endurance approx. 60-90 min
- Related lists
- "RQ-11 Raven". GlobalSecurity.org. Archived from the original on 21 January 2009. Retrieved 2009-01-09.
- Tomlinson, Cpl Ryan L (2008-05-14). "Gunfighter debuts Raven". IIMEF, Official Site US Marine Core, 2nd Light Armored Reconnaissance Bn. Retrieved 2010-02-23.
- "RQ-11 Raven". Army-technology.com. Retrieved 2009-10-09.
- "RQ-11 Raven datasheet". AeroVironment. Archived from the original on 3 January 2010. Retrieved 2010-02-08.
- Solar Raven - SUASNews.com, November 17, 2012
- "Gallery: The Complete UAV Field Guide; Current: RQ-11B Raven (AeroVironment)". Popular Science. February 23, 2010. Archived from the original on 30 March 2010. Retrieved 2010-03-01.
- "US Raven "loan" to MoD". UAV News. October 3, 2006. Archived from the original on 14 October 2006. Retrieved 2006-10-30.
- "Netherlands Ministry of Defence: Raven Small UAS ready for use". Defensie.nl. September 1, 2009. Retrieved 2009-09-01.
- "Vliegende nachtkijkers ingezet tijdens jaarwisseling". Defensie.nl. January 1, 2009. Retrieved 2010-01-04.
- "AlmereSpionagevliegtuigje ingezet tegen inbraken". OmroepFlevoland.nl. January 28, 2013. Retrieved 2013-01-28.
- "US to Provide 85 Hand-Launched RQ-11 Raven UAVs to Pakistan". Pakistan Military Review. April 21, 2011. Retrieved 2011-11-30.
- "US allocates US$145 million to fight terrorism in north, east Africa". defenceWeb. June 29, 2011. Retrieved 2011-07-07.
- "New Bird of Prey Hunts Somali Terrorists: Raven Drones". Wired.com. June 27, 2011. Retrieved 2011-07-07.
- "Czech military to buy two MUAVs for Afghanistan". ČTK (Czech Press Agency, www.ctk.cz). October 2, 2009. Retrieved 2009-10-02.
- "Iraqi Army's UAVs give troops the big picture". Army.mil. Retrieved 2010-03-28.
- "Lebanon to receive US-built UAV's". defence.professionals (defpro). April 16, 2009. Retrieved 2009-04-16.
- "Heavy U.S. Military Aid to Lebanon Arrives ahead of Elections". Naharnet Newsdesk. April 9, 2009. Retrieved 2009-04-09.
- "Lebanon gets Raven mini UAV from U.S.". United Press International. March 23, 2009. Retrieved 2009-03-24.[dead link]
- US delivers military vehicles to Lebanese Army. Daily Star, March 24, 2009.
- "RQ-11 Raven". Popular Science: 12. March 2006.
|Wikimedia Commons has media related to: RQ-11 Raven|
- Army-Technology RQ-11 Raven Project Details
- RQ-11 Raven Details on Globalsecurity.org
- Newsweek's Interactive Graphic. Raven: The Tiniest Drone
- Video of RQ-11 Raven launch from building in Najaf, Iraq
- Danish page about Raven
- AeroVironment, Inc.
The next one is the beginning of the "Potentially Lethal Drones" listed in the Time magazine article on Page 30 and 31 in the Feb. 11th 2013 issue with the Predator Drone on the cover.
It is 2 feet long. It's primary function is to "home in on Snipers" and to go to them and blow them up along with itself.
begin quote from Wikipedia under the heading "Switchblade"
en.wikipedia.org/wiki/AeroVironment_SwitchbladeThe operator looks through a viewer that displays video from the drone. Switchblade can also be directed to co-ordinates using Global Positioning System (GPS) ...
From Wikipedia, the free encyclopedia
|Primary users||United States Army
United States Marine Corps
DesignThe Switchblade has a small warhead and is launched from a 60 cm long container/launcher tube. As it launches its small wings unfold and can be guided to its target via a nose-mounted camera. The operator looks through a viewer that displays video from the drone. Switchblade can also be directed to co-ordinates using Global Positioning System (GPS). Powered by an electric motor it can reach speeds up to 80 kilometres per hour (50 mph) and loiter for up to 40 minutes. The Switchblade weights 1 kilogram (2.2 lb) and can be fired from a man-portable launch tube or a 70 mm rocket pod. It is operated by the same equipment used to control other AeroVironment UAVs. The explosive effect of the warhead is about equivalent to a hand grenade.
HistoryThe Switchblade was first tested in 2010 by the United States Army. 10 were purchased for evaluation and were deployed successfully. In September 2011, the Army ordered over a hundred for troop use. The Army then issued a $5.1 million contract modification effective March 20, 2012 to their previous order to produce and deliver more systems.
In May 2012, the United States Marine Corps ordered the Switchblade UAV.
- Aerovironment Switchblade - Aerovironent
- http://defense-update.com/products/s/switchblade_31122010.html Defense Update
- Switchblade enters service - Strategypage.com, September 24, 2011
- U.S. Army Awards AeroVironment $5.1 Million Order for Switchblade - Aerovironment press release, May 23, 2012
- Marine Corps pursues ‘kamikaze’ drone - Marine Corps Times.com, May 16, 2012
|This article on an unmanned aerial vehicle is a stub. You can help Wikipedia by expanding it.|
end quote from:
The next one is the only sea drone mentioned in this grouping at Time magazine the drone issue at the top of the page on page 31. It is called the Sea Fox. It is a small, maneuverable underwater drone that searches for anddestroys floating mines. Last year the Navy deployed it in the Straight of Hormuz.
From Wikipedia, the free encyclopediaThe Seafox is anti-mine marine drone. It is an expendably-priced, hunter-killer remotely operated vehicle (ROV) manufactured by Atlas Elektronik to destroy ground and moored mines.
- www.naval-technology.com/contractors/mine_disposal/atlasThe SeaFox I, a small, reusable and unmanned underwater drone, is used for inspection, identification and training purposes, while the identical combat vehicle ...
- gizmodo.com/.../the-strait-of-hormuz-will-keep-flowing-thanks-to-th...Jul 16, 2012 – The SeaFox Mine Sweeper Will Destroy Iran's Explosives in the Strait of ... up Iran's mines with smaller, American drone mines like the SeaFox.