Tethered Drones or UAS, Hovering platforms, and Towed parafoil system provide long range Communications and Surveillance for Combatting terrorism

Rajesh Uppal October 5, 2022 AI & IT, Security, Unmanned Comments Off on Tethered Drones or UAS, Hovering platforms, and Towed parafoil system provide long range Communications and Surveillance for Combatting terrorism 1,738 Views

Militaries have long recognized the advantages of height for surveillance platforms to overcome the Horizon limitations because of curvature of earth, therefore it has been using many such platforms like baloons, and aerostats. Security forces have also found that countering today’s asymmetric threats, which can occur at any time and place, requires reliable, cost-effective persistent surveillance systems and platforms.

The increased demand for remote communications and intelligence, surveillance, and reconnaissance (ISR) has driven interest in drones. ISR is the coordinated and integrated acquisition, processing and provision of timely, accurate, relevant, coherent and assured information and intelligence to support commander’s conduct of activities. Land, sea, air and space platforms have critical ISR roles in supporting operations in general. Effective ISR data can provide early warning of enemy threats as well as enable military forces to increase effectiveness, coordination, and lethality, and demand for ISR capabilities to support ongoing military operations has increased. Examples of ISR systems include surveillance and reconnaissance systems ranging from satellites, to manned aircraft such as the U-2, to unmanned aircraft systems such as the US Air Force’s Global Hawk and Predator and the US Army’s Hunter and PSST Aerostats, to other ground-, air-, sea-, or space-based equipment, and to human intelligence teams.

Tethered Unmanned Aircraft systems, towed parafoil systems and tethered Aerostats have emerged as low cost, local area surveillance systems that can provide surveillance for many days and can provide on demand launch over area of interest. The tethers allow them to carry long range surveillance, provide them power so that they can fly for long as well as help them withstand high winds. These systems can provide wide range of long-range surveillance and observation applications such as law enforcement, search-and rescue (SAR), homeland security and defence.

The military, law enforcement, and border patrol use tethered drones as an integral part of their remote security drone operations. Drones can cover a large area at once. The operators can monitor activity from the live feedback transmitted to a corresponding tablet or screen on the ground. This real-time feedback and video aids in criminal aerial surveillance, crowd safety, and military tactics. A mobilized drone station allows operators to move the flight area without having to land the drone first.

In 2016 Summer Olympics in Rio de Janeiro, Brazil, the ADB-150 Aerostat was deployed above the Olympics area to support the Brazilian Air Force security. The SHAPO’s gyro-stabilised three gimbal EO/IR surveillance payload was deployed on the ADB-150 aerostat to provide continuous surveillance, monitoring and public security. That military-grade security system gives Border Patrol agents a bird’s eye view of the Rio Grande Valley. Recently in March 2019 Sheriffs from around the country were granted a behind-the-scenes look at security operations at the Southern border. “This Aerostat has assisted Border Patrol in Rio Grande City by providing a higher level of surveillance and detection and increasing our situational awareness,” Olivares said, “Thereby allowing us to appropriately respond to threats as they’re crossing the river and even before they cross the river.”

Tethered drones are especially helpful for search and rescue missions. When tragedy strikes, a drone is a quick and efficient way to gather information about the scene. Drones equipped with radar and thermal sensors give first responders the needed information for understanding the scope of the disaster and locating trapped survivors. Their small size also allows them to get close-ups of areas a helicopter would not be able to and drop in needed supplies to rescuers and survivors.

Tethered Drones

There are variations of tethered drones, ranging from a standard drone tethered to the ground by using a regular fishing line, to programmed drones that use a specialized hardware tether. Specialized tethers utilize a high voltage, direct current to operate. The tether cable contains lightweight and thin conductors, which reduce the wind drag, enabling the drone to reach a higher altitude (around 400 feet).

A Power station (aka drone station or tether station) on the ground converts AC electricity into the higher-powered DC. The drone itself also has a DC-DC converter to supply lower-voltage power to the camera system and other components. Tethered drones are also easy to extract and retract using a winch system to which they are typically connected.

A tethered UAS has a reduced spatial area where it can fly. Because of the flying restrictions the tether creates, and their greater control, their operation does not require a trained pilot. It also does not require GPS navigation, which is a significant contributor to reducing any technical errors that lead to drones crashing. Normal Drone are prone to crashes due to technical or human error. Tethered drones dramatically reduce technical and human error crashes in flight.

The design challenges for the tethered architecture are mainly directed to the power supply system. Power must be delivered from the host ship to the multi-rotor drone at very high voltage and low current to allow the use of thinner and lighter hardware resources, which in turn allows greater mobility of the drone and higher air payloads.

The weight, dimensions, and electrical properties of the tether have a direct impact on the performance of tethered drones. The power delivery network (PDN), in turn, has a direct impact on the tether design. To enable a thinner and lighter tether, power must be delivered from the host ship to the drone at very high voltage and low current. This allows greater mobility and heavier aircraft payloads, which leads to improved communications and surveillance.

The many benefits of a tethered drone system include:

Persistent Operation: The continuous power delivered to Tethered drones make them persistent systems that can remain airborne for hours, if not indefinitely. Many tethered drones have longer flight times compared to free-flying, battery-operated drones. Free-flying drones have an average flight time of twenty minutes on a single, full charge. Most tethered drones have an unlimited flight time and can stay afloat until a problem occurs within the grounded power source, such as a motor or propeller failing.

Secure data: The tether means secure communications, unjammable, and immune to interference.

Overt Deterrence: Tethered drones are an overt surveillance deterrent.

Continuous Streaming: Tethered systems allow continuous and interference-free high-quality video broadcast. Free flying drones require a lot of skill and several hours of practice to operate efficiently. Due to the restricted movement of a tethered drone, the operator does not need piloting skills and can mainly focus on their tasks. The tether stabilizes drone movement, which enables capturing clear photos and videos; this is especially helpful for photographers.

Safe Operation: In crowded areas, public safety is essential. The tethered drone is dramatically more reliable than alternatives.

Free-flying drones are defined as unmanned aircraft, subjecting them to many rules and regulations set by the FAA. Tethered drones are considered Professional Unmanned Aerial Systems. Commercial use of drones was permitted by FAA Rule 107, and Tethered Drones are not exempt.

Tethered Drones for ISR and Security

Elistair is a French and US-based company founded in 2014. Elistair is a market leader in tethered drones supplying both DIY and Integrated systems. They have over 300 customers worldwide using their specialized tethered drone systems, and Elistair tethered drone has won several awards and competitions in France and The United States.

Hoverfly Technologies is a Florida based company. Hoverfly was founded in 2010 and has a long and proven history of innovative and first-to-market technologies, including the first tethered-power sUAS (the LiveSky™), the first optionally tether-powered free-flying drone (the BigSky™), and the first power-tether kit for consumer drones. Hoverfly designs and manufactures tether-powered aerial drones and third-party power tether kits.

Drone Aviation Corp. was founded in 2014, and recently merged with ComSovereign Corp. and is based in Florida. Drone Aviation designs, develops, markets, and sells specialized tethered aerial monitoring and communications platforms serving national defense and security customers for use in situational awareness applications including intelligence, surveillance, and reconnaissance (“ISR”) and communications.

CyPhy Works, founded in 2008, recently rebranded as Aria Insights. The new company focuses on utilizing artificial intelligence and machine learning to help analyze data collected by drones. Aria will build upon CyPhy’s tethered flight data collection system, to help pull information in dangerous situations from oil tankers and pipelines to natural disasters.

The AeroVironment’s “Tether Ey”e unmanned aircraft system is designed to provide continuous, 24-hours-a-day surveillance at up to 150 feet above its launch point. Tether Eye deploys automatically from a small, weather-sealed, self-contained base station and ascends to a pre-determined hover altitude from where viewers of its video feed take advantage of its 360-degree field of view.

“Tether Eye effectively complements our family of small unmanned aircraft systems by providing a valuable new capability – continuous ISR and security for buildings or stationary vehicles in defense, security and commercial applications,” said Kirk Flittie, AeroVironment vice president and general manager of its Unmanned Aircraft Systems business segment.The specially designed and ruggedized tether connecting Tether Eye to its base station provides continuous power, which, combined with AeroVironment’s track record of proven reliability, enables uninterrupted long-term operation.

“Having the ability to deploy a ‘virtual observation tower’ at a moment’s notice above buildings and vehicles represents a game-changing capability for ISR and security operations that has the potential to save lives,” said Amanda Toman, Program Manager at the CTTSO. “We look forward to continuing our evaluation of Tether Eye’s capabilities with AeroVironment as a possible deployable capability across government facilities.”

Current Tether Eye payloads include electro-optical (EO) and infrared (IR) cameras and AeroVironment’s encrypted Digital Data Link (DDL). The EO/IR camera provides both day and night imagery with full motion video transmitted directly to a Ground Control Station (GCS) that operates each platform within AeroVironment’s market-leading family of small UAS and Tactical Missile Systems. The Digital Data Link, integrated into each of AeroVironment’s platforms, provides secure communication with the unmanned aircraft system and communications relay with other platforms.

Sky Sapience Hovermast

HoverMast 100 is a tethered hovering platform that enables unlimited 24/7 continuous operation running on electricity from a silenced generator installed on the vehicle, It can be tethered on a wide range of platforms like UGVs/USVs (unmanned ground /surface vehicles), pick-up trucks, boats, ATVs, communication vehicles, etc.The hovering Micro Air Vehicles have the operational flexibility of being able to take off vertically, hover and land vertically, but usually they have limitations in forward flight, such as low speed and poor endurance. Sky Sapience has developed Hover Mast that has removed both of these constraints.

The system is capable of carrying any payload of up to 6 kg, such as CCD/IR cameras, radars, laser designators, relays, cellular antennas, and hyperspectral sensors and can receive COMINT and ELINT. Hovermast can trace a tank from a distance of 3km and a person from a distance of 1km.It can also be deployed and undeployed very rapidly, after the ignition button is pushed, it flies to heights of up to 50 meters within 15-20 seconds. It combines advanced flight algorithms, for high stabilization and materials like composites, lightweight motors and lightweight, high strength tethers to provide the highest payload-to-size ratio available today.

It can satisfy the needs of the army and security forces in a wide range of applications like Border control, Port security, Federal and local law enforcement, Anti-terror activities, Critical infrastructure protection, Mega event protection and crowd control, Special forces, infantry and naval operations and Urban warfare.The HoverMast-100 has been delivered to the IDF Ground Forces and is currently operational in several countries around the world for military and HLS missions.

The HoverMast-120 is a larger version of the HM-100. It rises to greater heights (up to 100 m) and is capable of hosting heavier payloads (up to 18kg). It is typically mounted on larger vehicles, and is suited for missions requiring extended operational and visual range.

Dragonfly Pictures (DPI) has developed a new class of drones, the tethered hover-in-place drone.

This new vertical take-off drone is weatherproof and can stay in the air for long periods of time. The drone uses a flexible cable as a permanent physical link to provide power and communications as well as mechanical support. DPI’s tethered drones are currently qualified for use by the U.S. Navy in marine/maritime environments for intelligence, surveillance, reconnaissance (ISR), communications, and video applications.

Unlike battery-operated multi-rotor drones that require a battery change every 20 minutes or a fast recharge, tethered drones receive power through an electrical cable connected to a base station. This allows them to remain operational for more than 400 hours at up to 500 feet above sea level – thanks to the continuous flow of energy through the tether. The tethered military/industrial-grade UMAR (Unmanned Multirotor Aerial Relay) drone is designed to track maritime and land-based platforms such as ships, boats, trucks, and other vehicles, in addition to the classic use as a base station for naval communications.

Tethers can be made of aramid or other lightweight synthetic materials to provide strength, with copper or plated copper for energy conduction and optical fiber for data and communications. The system can be ground-based or vehicle-based. Tethered drones, which hover hundreds of feet above a ship, overcome the challenge of ship communication systems that are limited by the curvature of the earth and can only communicate in line of sight with the horizon. Tethered Unmanned Aerial Systems (UAS) can provide continuous communications Beyond Line of Sight (BLOS). The tether provides continuous power and command/control to the UAS, thus greatly increasing the duration of the mission. Connected UAS systems reduce operator workload and mission planning, allowing the host ship and the off-board resource to communicate longer.

Compared to classic drones, these offer vertical take-off and landing capabilities. No runway, launch, or recovery equipment is required. They also offer good performance in turbulent weather, rain, snow, dust, and heat and are optimized for saltwater marine environments. The tether eliminates the dangers of electronic interference and therefore makes the system autonomous from GPS and radiofrequency. DPI’s tethered drones are currently qualified for use by the U.S. Navy in marine/maritime environments for intelligence, surveillance, reconnaissance (ISR), communications, and video applications.

Drones typically provide up to a few hundred meters of operational altitude, with the limiting factor being the ability of the drone to support the weight of the tether. Tethers can be made of aramid or other lightweight synthetic materials to provide strength, with copper or plated copper for energy conduction and optical fiber for data and communications. The system can be ground-based or vehicle-based.

“UMAR can host a variety of sensors including cameras, radar, and weather data can be collected at altitude for an extended duration. DPI has tested its tethered UAS systems on various vessels from 45 ft US Coast Guard vessels, US Navy ships, and US Army ground platforms,” said Joe Pawelczyk, vice president of operations at DPI.

The UMAR could be a useful tool to communicate with unmanned surface ships during defense and commercial operations. The UMAR could also be a back-up for telecommunications as a backhaul method for mobile communications at sea. Its potential applications include a base station for communications in offshore oil and gas and renewable energy operations. For longer distances, multiple daisy-chained drones can be used.

Power Challenges

The power levels are of the order of 8 to 10kW; under these conditions, UMAR drones are extremely powerful and robust and can maintain persistent stationary positioning in turbulent conditions affecting the positioning of the host ship. Inside the multi-rotor drone, the high voltage conversion must be done with the smallest footprint possible and with a form factor that reduces space and thermal effects. To meet these aggressive power challenges, DPI employs low-profile Vicor high voltage BCM VIA modules within its UMAR to enable high efficiency (98%) conversion with only 2% loss and heat from 800V to 50V.

To power the eight independent drone rotors, DPI uses eight Vicor high-voltage BCM4414 fixed ratio DC-DC converters. These modules have intrinsically low EMI with few high-frequency harmonics. Integrated EMI filtering within the Vicor BCMs helps minimize EMI noise by adding less size and weight than conventional DC-DC converters. “Using Vicor power modules, we have been able to lower the weight of all the components onboard the drone to increase altitude and airspeed while carrying the required mission payload,” said Pawelczyk.

UAV Corp’s Lighter Than Air Detachable Drone Completing Avionics Installation, reported in March 2022

UAV Corp has announced the near completion of the new Lighter Than Air Detachable Drone “LTATDD SA-70” with the avionics installation in its final stage and integration of subsystems before flight. Over the past three years UAV Corp’s wholly owned subsidiary Skyborne Technology, Inc. has designed, developed and is currently completing the manufacturing of innovative technology to provide disaster relief, communications, agriculture assessment, public safety, defense and other functions for domestic and international customers.

The LTATDD SA-70 semirigid structure encompasses a helium-filled, lighter-than-air (LTA) drone, fixed site mooring and tether controls as well as the LTA Drone is unique in that it allows the command-and-control personnel to release the tether and initiate flight as a remotely piloted unmanned airship.

The LTATDD SA-70 will be equipped with a modular pod (APOD) system which includes the flight deck and housing for up to two (2) unmanned drones for in-flight launch. Our first LTATDD SA-70 will be utilized for FEMA Disaster Relief efforts for the State of Florida through the Triumph Fund-Gulf/Coast State College Program. Our market research after Hurricane Michael and ongoing dialog with government agencies such as Homeland Security, Customs and Border Patrol, Naval Warfare Center, FEMA, Air Force, and other government agencies led to new advanced designs for the build of the LTATDD SA-70-12.

During the LATDD SA-70’s development, the company has re-engineered all hard structures, outer/inner envelopes, new UAS drone decks and an avionics suite for manned and unmanned capabilities. The hard structure CAD designs that can be transferred from aircraft aluminum to composites which could reduce the LTA Drone weight allowing for additional future surveillance and telecommunication systems. The avionics suite is a state-of-the-art system for remotely piloted operations.

“The company chose to invest in advanced technologies to be ahead of the curve for a total aerial communication system at an affordable cost,” stated Michael Lawson CEO. With the planned infrastructure upgrades to UAV Corp’s Costin Airport improvements will give the company a well-equipped operating base to complete the planned test flights of their LTATDD.

“I am pleased to report that the Gulf County Commission unanimously approved a motion to go out for construction bids to provide the $1,034,000 in infrastructure support to develop UAV Corp’s Skyborne hangar and operations facility in Port St. Joe Florida. The scope of work includes paving Cessna Drive and provision of water, sewer and electricity. We are excited by the possibilities and look forward to assisting UAV Corp in making this facility a reality!” stated Jim McKnight, Executive Director Gulf County Economic Development Coalition.

We continue to show that we are building our proprietary new technology to benefit both commercial, military and humanitarian opportunities. We believe that focusing our business directive on these markets will provide future growth and continue to add value for our shareholders.” stated Billy Robinson, Chairman. (Source: UAS VISION)

Military-grade Aerostat technology

Another comparable system is Rapidly Elevated Aerostat Platform (REAP) of Lockheed Martin, that was used in Iraq. This 31-feet long aerostat, operates up to 300 feet (91.44 meter) above the battlefield, takes approximately 5 minutes for rapid deployment from the back of a HMMWV and carries daytime and night vision cameras. Its sensors can see out to 18 NM (33.34 Km) from 300 feet. It provides endurance of upto 10 days.

Alberto Olivares is a Special Operations Supervisor, and cited statistical improvements in tracking capabilities. “This Aerostat has assisted Border Patrol in Rio Grande City by providing a higher level of surveillance and detection and increasing our situational awareness,” Olivares said, “Thereby allowing us to appropriately respond to threats as they’re crossing the river and even before they cross the river.”

The large white balloon was previously used in military operations in the Middle East. Its heavy-duty material can withstand gunfire. The Aerostat is tethered to the ground and flies at about 4,500 feet in the air, depending on wind conditions. Two 360-degree cameras attached to the balloon allow Border Patrol agents to view live video feeds from ten to 15 miles in any direction. “There’s a lot of smuggling of all kinds. Human and other, in this area, so it’s really increased our effectiveness here,” Olivares said.

Large groups of armed immigrants have been known to enter the country illegally through their property. “Groups of twenty to sometimes thirty,” Jody Guerra said. “Most of them carrying backpacks and there’s usually one or two people with rifles or weapons on them.”

DARPA’s Towed Airborne Lift Of Naval Systems (TALONS) prototype

The US Defense Advanced Research Projects Agency (DARPA) has successfully tested a towed airborne lift of naval systems (Talons) prototype. This low-cost, fully automated parafoil system can be towed behind boats or ships and also can be deployed by hand from smaller boats, or by mast from larger ships

These systems would provide long-range intelligence, surveillance and reconnaissance (ISR) and other capabilities over greater distances and time periods than helicopters and would require far less dedicated infrastructure resources than conventional fixed-wing manned and unmanned aircraft.Talons are designed to extend maritime vessels’ long-distance communications and improve their domain awareness. The system will be capable of carrying intelligence, surveillance, reconnaissance and communications payloads of up to 150lb between 500ft and 1,500ft in altitude, which is higher than current ships’ masts.

In 2016, DARPA’s Anti-Submarine Warfare (ASW) Continuous Trail Unmanned Vessel (ACTUV) program developed and built a technology demonstration vessel with its first payload: a prototype of a low-cost, elevated sensor mast developed through the Agency’s Towed Airborne Lift of Naval Systems (TALONS) research effort. While aloft, TALONS demonstrated significant improvements to the range of the sensors and radios it carried compared to mounting them directly on a surface vessel. For example, TALONS’ surface-track radar extended its range by 500 percent—six times—compared to its range at sea level. Its electro-optical/infrared scanner doubled its observed discrimination range. The TALONS team plugged in a commercial handheld omnidirectional radio; that radio’s range more than tripled.

Talons is part of DARPA’s Phase 1 research for Tern, a joint programme between DARPA and the US Navy’s Office of Naval Research. Tern seeks to give forward-deployed small ships the unprecedented capacity to serve as mobile launch and recovery platforms for medium-altitude, long-endurance unmanned aerial systems (UAS).

DARPA’s SideArm effort seeks to create a self-contained, portable apparatus able to horizontally launch and retrieve UAS of up to 900 pounds from trucks, ships and fixed ground facilities. The small-footprint system is designed to enable rapid setup and controlled decelerations and adapt to current and future UAS. Based on subscale tests last summer, DARPA will conduct further risk reduction and hardware testing this year, and then plans to test recovery of two different aircraft types at full scale. “Through SideArm, TALONS and other projects, DARPA aims to make it much easier, quicker and less expensive for the Defense Department to deploy persistent ISR and strike capabilities almost anywhere in the world,” said Dan Patt, DARPA program manager.

DARPA demonstrated TALONS capability aboard US Navy vessel in 2017

DARPA has already demonstrated that TALONS ( low-cost, elevated sensor mast carrying ISR payload ) could also be useful in Warfare where they could extend the range of Unmanned Surface Vehicles used for submarine tracking and countermine activities.

In 2017, The Defense Advanced Research Projects Agency (DARPA) tested a prototype of a low-cost elevated sensor mast on-board the US Navy’s commissioned Cyclone-class patrol coastal ship USS Zephyr for the first time. The three-day trial period saw the crew of the 174ft-long naval vessel evaluate the prototype of DARPA’s Towed Airborne Lift of Naval Systems (TALONS) near Naval Station Mayport, Florida.

TALONS exhibited safe and routine operation from USS Zephyr’s deck under different sea states and wind conditions during the trials, without adversely affecting the vessel’s operational capability. The system also significantly improved USS Zephyr’s communication range between itself and remote platforms such as the vessel’s rigid hull inflatable boats (RHIBs). It also enhanced the ship’s capacity to detect, track and classify objects of interest.

In addition, the test showed that TALONS could persistently suspend intelligence, surveillance and reconnaissance (ISR) instruments and communications payloads of up to 150lb when towed behind boats or vessels at altitudes between 500ft and 1,500ft above sea level. DARPA Tactical Technology Office programme manager Scott Littlefield said: “We’re very pleased with the USS Zephyr testing, which showed that a future system based on TALONS could provide operational benefits for even small navy vessels.” Littlefield added that the organisation intends to continue its collaboration with the US Navy next year in order to work towards the full automation of launch and recovery operations.