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1 INTRODUCTION

Unmanned aerial vehicles (UAVs) and autonomous

underwater vehicles (AUVs) are being increasingly

used for numerous purposes in both military and

civilian areas. Today’s applications of these systems

include surveillance, reconnaissance, remote sensing,

target acquisition, border and marine patrol,

infrastructure monitoring, communications support,

aerial imaging, industrial inspection and emergency

medical support. The UAVs and AUVs have

capacities of sensing and perceiving the environment,

processing the sensed information, communicating,

planning and decision making, as well as acting

autonomously by using control algorithms and

actuators [5]. The UAVs and AUVs presented in this

paper are deployed within EC Horizon 2020

COMPASS2020 (Coordination Of Maritime assets for

Persistent And Systematic Surveillance) project. This

project has a goal to use unmanned aerial and

underwater vehicles in operational coordination with

manned oceanic patrol vessels used by European

Maritime Safety Agency (EMSA), to enhance current

marine border surveillance operations, with a

particular focus on the detection, monitoring and

control of irregular migration and narcotics

smuggling. The project has been conceived to assist

authorities in handling the pressure put on European

external borders by the vast amount of irregular

border crossings observed in recent years. Besides

struggling with irregular migrants, Europe has a

problem with other incidents of the most disperse

nature such as the long lasting issue of narcotics

trafficking [11]. Aiming to address these two big

challenges, the project proposes the development of

an unified system based on open standards that will

enable the combined operation of multiple unmanned

assets, manned platforms currently used for marine

surveillance and the future accommodation of other

platforms and services with minor integration efforts

[7;8;18].

Performances of Some Autonomous Assets in Maritime

Missions

S. Bauk

Durban University of Technology, Durban, South Africa

ABSTRACT: The paper deals with key features of some autonomous assets, i.e., unmanned aerial and

underwater vehicles used for marine surveillance and reconnaissance missions. Firstly, performances of Airbus

Zephyr S HAPS (Solar High Altitude Pseudo-Satellite), Tekever AR5 Life Ray Evolution and the AR3 Net Ray

medium altitude unmanned aerial vehicles (UAVs) have been analysed. Then, ECA Group A18 and A9

autonomous underwater vehicles (AUVs) features have been presented. The strengths, weaknesses,

opportunities and threats (SWOT) approach is applied to position appropriately these UAVs and AUVs in the

context of maritime security operations. The need for further investigation in the field is reveiled as well. The

analysed vehicles are assets deployed with the Europen Commission’s (EC) COMPASS2020 project and tested

over European seas.

http://www.transnav.eu

the International Journal

on Marine Navigation

and Safety of Sea Transportation

Volume 14

Number 4

December 2020

DOI: 10.12716/1001.14.04.12

876

This article concerns key performances of the

UAVs and AUVs at a high level of abstraction, used

within COMPASS2020, and it is organised as follows:

Section 2 deals with UAVs: Airbus Zephyr S HAPS,

Tekever AR5 Life Ray Evolution and AR3 Net Ray;

Section 3 considers AUVs: ECA Group A18 and A9

assets; Section 4 gives a SWOT analysis of examined

UAVs and AUVs, which can be considered as an

original contribution of the article; while the last

Section 5 gives conclusion and indicates directions for

further investigation in the field.

2 KEY FEATURES OF SOME UNMANNED

AERIAL VEHICLES

In this section general features of UAVs as Airbus

Zephyr S HAPS, Tekever AR5 Life Ray Evoulution

and AR3 Net Ray have been given. The inspiration for

selecting these particular UAVs is found, as it is

already noted, in recently set up EC Horizon 2020

COMPASS2020 project.

2.1 Airbus Zephyr S HAPS

The Zephyr is the first unmanned aircraft capable to

fly in the stratosphere, harnessing the sun’s rays and

running on a combination of solar cells and high-

power lithium sulphur batteries (solar-electric power)

above the weather and conventional air traffic. It is a

High Altitude Pseudo-Satellite (HAPS) [18;21]

capable to fly for almost a month at a time

combining the persistence of a satellite with the

flexibility of an UAV (Figure 1). As HAPS, the Zephyr

uses high-definition electro-optical and infra-red

cameras to produce real-time visuals in any lighting.

It costs around 5 million US$, while an orbital

satellite costs between 50 and 400 million US$ [22], so

it is considerably cheaper than a satellite. At the

moment, Airbus possesses two types of the Zephyr,

designed to accommodate a variety of payloads. The

production model Zephyr S has a wingspan of 25 m

and weighs less than 75 kg. It is able to carry see,

sense and connect payloads. Presently, the larger

Zephyr T, which is under development, has a

wingspan of 33 m and a Maximum Take-Off Weight

(MTOW) of 140 kg [2].

Figure 1. Airbus Zephyr S HAPS in stratosphere (Source:

Airbus)

The Airbus Zephyr S has been firstly launched on

11 July 2018 in Yuma, Arizona, USA. Previously, it

was transported from Farnborough, UK. It had a

small ground infrastructure. This was a historical

take-off, when after eight hours Zephyr reached the

stratosphere. Its lower altitude was 18 km, and the

highest 23 km. This was, at the time, the longest flight

without refueling, lasting 25 days, 23 hours and 57

minutes [1]. Unfortunately, on 15 March 2019, the

Zephyr aircraft crashed near its launch site in

Wyndham, Western Australia [19]. This was caused

by severe adverse weather. Luckily, it happened in an

extremely remote location and caused no injuries or

property damage. Work on the Zephyr improvements

is continued and it is to be expected that the Zephyr’s

mechanical launcher will be tested soon.

Zephyr sees clearly, senses efficiently, and

connects precisely. It is able to revolutionase missions

all over the world, including defence, humanitarian,

security and environmental operations. It shapes the

future of connectivity. Zephyr delivers new services,

new business models and new opportunities to the

connectivity market. It is flexible, scalable and

connects beyond. Zephyr detects and tracks vessels in

all weather through High Altitude Radar Persistent

Imagery (HARPI) within the range of 35 nm (Figure

2). It is suitable for adaptive missions planning at

distances greater than 100 nm (Figure 3). In addition,

it cues other air assets to investigate; provides

situational awareness to maritime agencies; enables

maritime network evolution; adds security and

resilience to the network, in a way to integrates it

with existing IP networks and like.

Figure 2. Zephyr vessels’ tracking by HARPI (Source:

Arbus)

Figure 3. Zephyr adaptive mission planning (Source:

Airbus)

The Zephyr was conceptually integrated in the

proposed COMPASS2020 architecture, as a valuable

asset for future concepts of operation. Due to its

potential of acting as a high altitude platform capable

877

of performing early detections and providing the

respective warnings to the system, it is considered to

bring added value to the solution, by providing

persistent surveillance and the first detection of

potential events of interest. The goal of the project is

to develop the solution in such a way that it will be

possible and simple to integrate the Zephyr (both

physically and in terms of data processing) within the

overall system, once this platform has reach a

development maturity that allows it to become fully

operational [7;8].

2.2 Tekever AR5 Life Ray Evolution

The AR5 Life Ray Evolution is a medium-endurance

and medium-altitude fixed wing UAV (Figure 4). It is

designed for wide area land and maritime

surveillance, pollution monitoring, fisheries

inspection and communication relay [10]. The AR5

Life Ray Evolution has advanced on board capacities

in terms of data processing. It can simultaneously

process Electro-Optical/Infra-Red (EO/IR), radar and

AIS data [17].

Figure 4. Tekever AR5 Life Ray Evolution (Source: Tekever)

The AR5 Life Ray Evolution is sub-tactical UAV

dealing with 180 kg MTOW. It allows high speed

beyond line of sight (BLoS) satellite communications

(SATCOM). It also provides high precision video,

imagery and sensor data in real time. Its features

include a flexible architecture, supporting multiple

types of payloads and datalinks. Moreover, this

platform complies with the highest production

standards as the first European-wide UAV-based

maritime surveillance system, which is International

Traffic in Arms Regulations (ITAR) free [13]. As an

UAV that requires a runway for take-off and landing,

its automatic take-off and landing capabilities, as well

as the fact that it can use short and unpaved airstrips,

are great advantages. The AR5 Life Ray Evolution has

a cruise speed of 100 km/h and a standard endurance

of approximately 16 hours. The available payload

capacity is up to 50 kg, wingspan 7.3 m and length 4.0

m. It is equipped with a three axis multi-sensor gyro-

stabilised gimbal, capable of supporting the

integration of multiple types of payloads. This

includes AIS transciever, multiple EO/IR sensors,

Emergency Position Indicating Radio Beacon (EPIRB),

radar, etc [24;27].

Within COMPASS2020, the AR5 Life Ray

Evolution UAV plays an important role as a middle

layer platform, which is able to provide wide

maritime area surveillance, complementing the

operational gap between the wider coverage but

lower resolution capabilities of the Zephyr, and the

lower altitude and more localized situation

monitoring provided by the AR3 Net Ray, which will

be presented in the following sub-section [6;8].

2.3 Tekever AR3 Net Ray

The AR3 Net Ray is a ship-borne UAV designed to

carry out several types of maritime and land-based

missions (Figure 5). These missions include:

intelligence, surveillance, target acquisition and

reconnaissance (ISTAR) actions, pollution

monitoring, infrastructure surveillance and

communication support operations. This UAV is

capable of delivering an endurance up to 10 hours,

which makes it an ideal solution to carry out both

maritime and land based missions. The payload

capacity is 4 kg and it includes: multiple options for

EO/IR sensors, near-infrared to long-wave infrared

(LWIR) sensors, laser illuminators, communication

relay systems, AIS transceivers and EPIRB. It

provides real time collection, processing and

transmission of high definition video. Its

communication range is up to 80 km within radio

Line of Sight (LoS), cruise speed is 85 km/h, MTOW is

23 kg, launch is conveyed via catapult, recovery via

parachute and airbags (for land based operations) or

using a net system (for maritime based ship-borne

operations). The AR3 dimensions are 3.5 m of

wingspan and a length of 1.7 m [26].

Figure 5. Tekever AR3 Net Ray taking-off (Source: Tekever)

The AR3 Net Ray UAV will be included in the

COMPASS2020 surveillance ecosystem as an organic

asset of the oceanic patrol vessels operated by the

maritime authorities. This UAV will be operated

(launched, piloted and recovered) from the vessel to

provide the tactical teams with enhanced real time

information to help decision making. The AR3 will

cover a surveillance level below the AR5, providing a

more localised monitoring of events and situations of

interest [6;8].

3 KEY FEATURES OF SOME UNDERWATER

UNMANNED VEHICLES

In this section, crucial features of AUVs as ECA

Group A18 and A9 are briefly presented. The

inspiration for selecting these particular UAVs is like

in the previous case of UAVs found within EC

Horizon 2020 COMPASS2020 project. These assets are

robots-drones that travel underwater without

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requiring input from an operator. They are

autonomous platforms, without cable, integrated

their own energy. In other words, they execute

missions autonomously. They are capable to follow a

programed pattern with very accurate positioning,

while navigating close to the seafloor with very good

stability. They provide high resolution images in

order to improve survey efficiency. These drone

systems are used for underwater mine warefare,

homeland security, crucial infrastructure protection,

harbor and coastal surveillance and protection, rapid

environmentas assessment (REA), search and rescue

(SAR) operations, intelligence, surveillance, and

reconaiance (ISAR), commercial applications

(offsore), and deep water survey and inspection. They

are lounched and recovered via robots [14].

3.1 ECA Group A18-M

The A18 is a configuration of ECA Group AUVs

family (Figure 6). Its applications for the defense and

security sector encompass: (i) Rapid Environment

Assessment (REA); (ii) Intelligence, Surveillance and

Reconnaissance (ISR); (iii) organic underwater mine

warfare: mine countermeasures mission module for

large multipurpose vessel and mission module for

oceanic mine warfare, and (iv) conventional

underwater mine warfare: detection and

classification. The system can be delivered with a

Launch And Recovery System (LARS) allowing

automatic underwater recovery. Data post processing

can be made with Triton imaging applications. It

performs autonomous missions up to 300 m depth,

and is easily transportable by plane for overseas

missions. Due to its large endurance, very high area

coverage rate (2km2/hour) and payload capacity, it is

able to host high performance payloads according to

the mission’s requirements as Synthetic Aperture

Sonar (SAS), Conductivity, Temperature and Depth

(CTD) sonde, video, forward looking sonar (FLS),

multi-beam echo sounder, and others [23]. For

navigation, it uses Inertial Navigation System (INS),

Doppler Velocity Log (DVL), military global

navigation satellite system (GNSS) and Global

Positioning System (GPS) periodically, after

resurfacing. It can communicate via WiFi, Ethernet,

Iridium and/or acoustic wireless communication

channel. Its average speed is 3-5 knots (while the

maximum is 6 knots). It withstands harsh

environmental conditions and offers a greater

stability when encountering heavy turbulence from

waves. The high degree of stability enables this AUV

to capture high-resolution images. The information

obtained by the platform is processed to the

command centre [15;9].

Figure 6. ECA Group A18 launching and underwater

mission (Source: ECA Group)

3.2 ECA Group A9

The A9 is a member of ECA Group UAVs family for

environmental monitoring (Figure 7). In addition to

the seabed image acquisition, the A9 AUV can record

bathymetric data as well as environmental

information such as water turbidity, conductivity,

temperature, fluorescence, dissolved oxygen and/or

pH. Mission planning and monitoring are done

through user friendly software which allows operator

to follow the vehicle at any time during its mission.

This underwater drone has been designed to meet

STANAG 1364 requirement; as such, its acoustic and

magnetic signatures are minimised in order not to

trigger any underwater mines when doing the mine

warfare survey. As part of early trials for the SWARM

project, ECA Group A9 fitted with the

interferometer sidelooking sonar demonstrated

ability to conduct surveys in a shallow water of 13-20

m depth. It uses a phase differencing bathymetric

sonar that increases area coverage by close to 200%

over conventional multi-beam echo sounders in

shallow water [16]. For navigation, it uses INS, DVL,

GPS and for communication purposes radio (UHF),

WiFi, Ethernet and the acoustic wireless

communications. Its payload consists of, but it is not

limited to: Interferometer Side Scan (ISS) sonar,

video, CTD, and environmental sensors (turbidity,

pH, fluorescent Dissolved Organic Matter (fDOM) /

waste water discharge).

Figure 7. ECA Group A9 (Source: ECA Group)

Within the COMPASS2020 project plans, the

AUVs are to be deployed from the offshore patrol

vessel into a strategic location that is coincident to the

traffickers’ typical routes. The AUVs are programmed

to follow circular trajectories in the area of interest,

navigating underwater at low depth in order to

remain undetected from the smugglers and at the

same time staying closely enough to the surface in

order to optimise the possibility of detecting the

target. The AUVs carry sets of hydrophones that

enable detecting speed boats and localise dumped

cargo (cases or bags with narcotics). After detection of

the target, the AUVs can communicate to the Zephyr,

which is used as a communication relay in the system

[11].

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4 SWOT ANALYSIS

This section deals with some basic positive and

negative factors connected with previously

introduced UAVs and AUVs. These factors are

summarised through a SWOT analysis (Table 1). In

accordance with SWOT principles, strengths,

weaknesses, threats and opportunities of the

considered UAVs and AUVs are highlighted. Current

solutions for analysed UAVs and AUVs are in

development and/or testing phases [12]. Therefore, it

was not possible to conduct surveys due to their

strengths, weaknesses, threats and opportunities

among potential endusers such as Europen maritime

and coastal authorities. Developers and researchers

involved in the project have dreated their oven

internal documentation, which is treated as the

intellectual property of the project. Therefore, the

following SWOT analysis is based mostly on

secondary literature resources [3;4;20;25] and some

information upon the results of the field experiments

recently being carried on. However, used references

are sound and promise quality of conducted study.

Through further investigation the examined features

of UAVs and AUVs can be assessed within the

specific context, which might be different from the

analysed one – European coastal areas monitoring

and combat against narcotic smugglers by the

maritime authorities. Apart from this, at the current

stage of the research in the field, the following SWOT

is at high level of abstraction and only partly

anchored to the afore mentioned project and its

setting.

Table 1. SWOT analysis of the UAVs and AUVs

__________________________________________________________________________________________________

Strengths

__________________________________________________________________________________________________

UAVs AUVs

__________________________________________________________________________________________________

- Lightness. - Capacity to support high risk activities.

- Manual launching or reduced logistics footprint. - Capacity to reach areas inaccessible for humans.

- Low energy consumption. - Capacity to explore unexplored marine habitats.

- Lower acquisition price in comparison to satellites. - Capacity to monitor and repair underwater constructions,

- Better quality of information in comparison with pipelines and cables.

satellites. - High level of autonomous navigation, collecting data and

- Lower operational costs in comparison with manned coming back to the seasurface vessel.

aircrafts used for the same mission profiles. - Silence operation and conseguently not disturbing the

- Ability to fly for more hours continuously in environment and being imperceptible to potential foes.

comparison to manned aircrafts, as there is no need for - Being tight and waterproof.

aircraft downtime for pilot rendition. - Having shape that mimics sea creatures (fishes, crabs, turtles,

- High seeing, sensing and communication capacities. beetles and snakes).

- Capacity of both LoS and BLoS operations. - High appropriateness of kinetic and dynamic properties for

- Large coverage and durability of flight without underwater environment.

recharging. - Capacity of delivering with a Launch And Recovery System

- High level of automation. (LARS).

- Possibility to be safely integrated with commercial - Navigation with combination of Inertial Navigation System

aviation. (INS), Doppler Velocity Log (DVL), military global

- Capacity to support high risk activities. navigation satellite system (GNSS) and Global Positioning

- Capacity to reach areas inaccessible for humans. System (GPS) periodically.

- Possesing advanced sensors like: Synthetic Aperture Sonar

(SAS), video, forward looking sonar (FLS), multi-beam echo

sounder and like.

- Communications via acoustic, radio and optical (light and

laser) waves.

__________________________________________________________________________________________________

Weaknesses

__________________________________________________________________________________________________

UAVs AUVs

__________________________________________________________________________________________________

- Complexity of the UAVs makes them more vulnerable. - Better adaptive control using neuro-fuzzy techniques is

- Requirements for highly skilled personnel for needed.

designing, creating, operating-controlling, maintaining - More accurate localising using improved INS non-linear

and upgrading the UAVs. Kalman filters, cooperative localization (swarm intelligence),

- Lack of law regulations at a wider scale. artificial intelligence vision and object detection, odometry,

- Lack of management and operational knowledge at are to be developed.

different levels of the UAVs operation. - Underwater wireless communications are to be improved,

- Lack of common communication capacities between particularly at the longer distances.

the UAVs and other vehicles within integrated traffic - High-density battery power supply is necessary.

and transportation system.

- The link between the UAVs and ground control stations. - Energy harvesting methods are to be improved.

- Maneuvering and obstacles’ avoidance algorithms and

features are under development.

- Computer vision is also still until development.

__________________________________________________________________________________________________

Opportunities

__________________________________________________________________________________________________

UAVs AUVs

__________________________________________________________________________________________________

- Increasing safety and security at sea and in general. - Increasing safety and security at sea and in general.

- Reduction of traffic congestion in areas with high - Approaching up to now inapproachable corners of seabed.

density traffic. - Approaching areas of high risk for humans.

- Approaching up to now inapproachable areas. - Gathering more information on distance areas, acquatic flora

- Approaching areas of high risk for humans. and fauna, constructions.

- Gathering more information on distance areas, - Lower ecological footprint.

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entities, constructions. - Developing 3D path planning with obstacle avoidance.

- Lower ecological footprint. - Developing potentials of autonomous systems.

- Developing 3D path planning with obstacle avoidance. - Further development of artificial super-complex AUV

- Developing potentials of autonomous systems. systems.

- Further development of artificial super-complex

UAV systems.

__________________________________________________________________________________________________

Threats

__________________________________________________________________________________________________

UAVs AUVs

__________________________________________________________________________________________________

- Collapse of the UAVs due to severe weather - Losing human control over the crafts.

conditions/harsh environments. - Unsafe Launch And Recovery System (LARS).

- Negative effects of external factors as natural forces - Internal disturbances and faults in the systems as super-

and cosmic impacts. complex ones.

- Losing human control over the crafts. - Over-reliance on technology, AUVs in the analysed context.

- Unsafe landing and recovering. - Unauthorised malicious intrusion into the system (hacking).

- Internal disturbances and faults in the systems as - Scarcity of the cost-benefit analysis.

super-complex ones. - High investment risks.

- Over-reliance on technology, i.e., UAVs in the analyzed - The lack of readiness of entrepreneurs to support further

context; development of AUVs.

- Unauthorized malicious intrusion into the system - Uncertain revenue of investments.

(hacking); - Users’ reluctance to accept high risk investments in the

- Scarcity of the cost-benefit analysis; AUVs innovations.

- High investment risks; - Questionable innovation acceptance success.

- The lack of readiness of entrepreneurs to support

further development of UAVs;

- Uncertain revenue of investments;

- Users’ reluctance to accept high risk investments

in the UAVs innovations;

- Questionable innovation acceptance success, etc.

__________________________________________________________________________________________________

5 CONCLUSION

A review of the UAVs and AUVs within the context

of the COMPASS2020 project has been given. The

Zephyr, the AR5 and the AR3 UAVs and A18 and A9

AUVs have been described through pointing out their

key features. Based on the findings from secondary

literature resources and experiences from the project

up to now, some strengths, weaknesses, opportunities

and threats of the considered UAVs and AUVs have

been highlighted.

The future research in this area should provide a

deeper insight of compatibility of the UAV and AUV

systems with the existing and well established

manned and unmanned crafts used for the same or

similar purposes. Common communication schemes

and algorithms among (un)manned, aerial, seasurface

and underwater craft are currently under further

development.

There is a strong argument in favour of increasing

initiatives for testing, validating and integrating

unmanned systems within current surveillance

infrastructures (both land and maritime based), as

these assets can assist current surveillance and

monitoring capabilities of authorities in a cost-

effective way. However, the so-called blind-belief in

technology, including the analysed UAVs and AUVs,

should be critically reviewed. The willingness of

various involved parties to develop, implement and

adopt such advanced systems should be investigated

with the aim to provide their innovation

implementation success in military, civil, industry

and other errands.

Such advanced systems can be used as subjects of

further research work and base for applying for

research funds not only in developed, but also I

developing countries as South Africa. The scope of

the analysed craft can be broaden beyond patroling

and combat missions in European seas. For instance,

the South Afican Operation Pakhisa programme

inspired by blue economy can inrich its scope by

investigating possibilities of optimal deploying the

UAVs and AUVs within the national context, in

accordance with the actual needs and preferences in

maritime.

ACKNOWLEDGMENT

This article has been inspired by Europen Commission’s

Horizon 2020 COMPASS2020 Project (Grant Agreement

No: 833650). The author is an external expert at the Project.

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