Drones Free Dome (DFD) - Zickel Engineeringzickel.net/pdf/ZickelEngineeringDroneFreeDome... · 7/15/2017 · Zickel Engineering Consulting and Training LTD Tel: +972-4-8769229, Fax:

Zickel Engineering Consulting and Training LTD

Tel: +972-4-8769229, Fax: +972-77-7009229, Web: www.zickel.net eMail: [email protected]

Page 1 of 20

The information included in this document is Zickel Engineering sole Intellectual Propriety (IP).

This IP should be used for the purpose of establishing venture with Zickel Engineering only.

Drones Free Dome (DFD) By Robert Zickel, Zickel Engineering Ltd

1. Scope

Our goal is to improve the level of civil safety in the up and coming drones’ era. This

document deals with anticipated operational needs of detection and interception of low

signature – low altitude UAVs (Unmanned Arial Vehicle), and describes the basics for a

system that protects selected assets and/or events.

The following information should be used according to Israel’s export legislation.

2. Introduction

The drones’ warfare is similar to the cyber warfare. The situation today is exactly the

same as in the beginning of the computer viruses and is similar to the early phases of the

cyber warfare.

We anticipate a wide usage of drones for legitimate missions in a fast evolving

environment – technical and regulatory.

The race can’t be stopped and the bad guys’ capabilities are already here and immediate

solutions are needed now, any solution will be evolving to meet future threats.

The use of low cost drones, such as quadcopters and hobby RC drones, for recreational,

commercial and security purposes is expected to ever grow in the decade ahead. The

result of this process will be an abundance of low cost drones accessible for all to

purchase or build freely.

Past experience shows that every new technology inherently attracts outlaws and terrorist

to adapt it for their activities. Hence, a simple threat analysis, taking into account this

obvious market trend together with past experience, predicts that the proliferation of

drones inevitably leads to criminal abuse of the technology.

As a response to the threat there will be regulations, laws and enforcement. The proposed

Drone Free Dome System provides protection against those who don’t obey the laws and

regulations.

http://www.zickel.net/



Page 2 of 20



2.1. Today’s Typical Threat

As a first step in the process of mitigating the drones’ threat, a survey of the existing and

available drones, the possible detection methods to detect them and possible methods to

intercept them was conducted.

A typical off-the-shelf drone uses efficient electric motors with efficient batteries, powerful

processor, MEMS (Inertial, Magnetic & Baro) & GNSS for sensing, modern data links,

cameras, and low weight composite materials structure. It has a flight endurance of up to

30 minutes within a typical radius of a few hundreds of meters (under mile). The drone

weight is 1-10Kg and half of it can be payload. Such a drone cost is in the range of a few

hundred dollars to a few thousand dollars. Sample of small UAVs is shown in Figure 1.

Figure 1 Samples of small drones

2.2. Recent Events of Exposure to the Threat

At present, in 2015, FAA lists about 150 reported events of drones in the vicinity of the

flight path per month! Superposing the above rather obvious prediction with this FAA

report reveals a scary picture of a disaster knocking on our door and ready to drop onto

us. Counter measures must be developed, but the development cycle of 3 to 5 years must

not start only after the first event materialised, leaving all of us exposed to the threat for

that period.




Page 3 of 20



To elaborate the previous statement, enclosed are just a handful of other examples from

recent events of people and sites that failed being kept secured, in spite of the obvious

necessity:

16 September 2013, Dresden, Germany,

A camera drone had a rough landing in front of Chancellor Angela Merkel at an election

campaign event in Germany after police told its operator to bring down the craft

(Figure 2).

https://www.youtube.com/watch?v=1-5MDqGGon8

Figure 2 Rough landing of a drone in front of Chancellor Angela Merkel

27 January 2015, Washington DC, USA

White House drone crash: drunk government employee crash lands Quadcopter on

Obama’s lawn. An investigation is still ongoing after a government worker reportedly

crashed his small recreational drone onto the White House lawn early Monday morning

(Figure 3).

https://www.youtube.com/watch?v=qRH6Ec82jR4

Figure 3 Illustration of a drone in front of the White House


https://www.youtube.com/watch?v=1-5MDqGGon8

https://www.youtube.com/watch?v=qRH6Ec82jR4



Page 4 of 20



05 November 2014, Belleville-sur-Loire nuclear plant, France

Police arrested three people found in possession of remote-controlled drones near one

of the nuclear plants involved in a series of mystery overflights by the unmanned

aircraft (Figure 4).

https://www.youtube.com/watch?v=xIaVWP34FO0

Figure 4 Illustration of a drone above a nuclear plant in France

2016, ISIS use of commercial drones for attacks (Figure 5).

https://videos.files.wordpress.com/TneJgWZZ/isis-ninawa_dvd.mp4

Figure 5 ISIS use of attack drones


https://www.youtube.com/watch?v=xIaVWP34FO0

https://videos.files.wordpress.com/TneJgWZZ/isis-ninawa_dvd.mp4



Page 5 of 20



3. Threat Detection Method

The main difficulty for an early detection of a drone imposing a threat is its low signature

which leads to a close range of possible detection. Short range corresponds to a very

short time of detection and response. Furthermore, a low-signature light UAV may be

launched from a very close range from its target, escalating the above mentioned

difficulty.

The first key element in achieving an effective defence over a specific, designated area

from such potential attack is short range fast detection with low rate of false alarms.

Achieving this objective is feasible only through multi-domain sensors fusion.

The proposed detection system is flexible, modular and scalable. In the heart of the

system, the real-time data-fusion, classification, and analysis, scenario driven algorithms

and software.

The sensors’ suit will be tailored according to the specific, designated area, the

anticipated threats and the possible scenarios.

For example, in rural areas, radar is beneficial over visual alone. However, for in an urban

area, the visual is crucial and today’s radar is inadequate.

3.1. Sensing

Table 1 summarizes the basic characteristics of some of the common detection methods.

Table 1 Available detection methods

Method Characteristic

Radar

Suites for use in open, unpopulated areas.

Problematic to use in densely populated areas.

For achieving effective results a scanning system is required or a

number of passively staring systems or a combination of the two.

Optics, Visual

Daylight use.

At dark, the need for an external light source restricted effectiveness.

Using a variety of cameras concurrently enables fast detection,

classification and verification process.

Optics, IR Most effective in dark / cold ambience.

Complimentary to the vision range wavelength. Combines SWIR/NIR.




Page 6 of 20



Laser Scanner Efficient pointing to suspect targets

Acoustics

Mostly a complimentary system for warning. Limited use in noisy

environment.

For some types of drones, in a quiet environment and with a properly

distributed array of microphones this method enables to detect angle of

arrival, velocity and the type of threat by its acoustic signature.

Radio

Suites for RC drones. Such drones use specific frequencies between

VHF up to 5.8GHz.

Locating the source of radio transmission enables neutralising the

operator and greatly decreases the false alarm rate while increasing the

probability of drone detection.

Cyber Details can not be disclosed at present.

3.2. From Data Fusion to Sinergy

In the heart of the threat detection and verification system lay a number of powerful

parallel distributed processing units which fully share information among themselves. The

system collects the data from all sensors and using advanced data fusion and pattern

recognition algorithms, some of which mimic human’s brain methods, it recognises any

abnormal patterns and behaviour. Thus, it is possible to identify multiple potential threats

in a complex scene. Table 2 demonstrates part of the sensors and their respective

contribution to the threat detection analysis.




Page 7 of 20



Table 2 Expected detection range with various sensors

Range, m 20 40 80 150 300 600

Threat level Acute High Medium Low None

Phase Verification Identification Detection

Radio

spectrogram

Phase Verification Identification Detection Suspicion

Visual

image

0.25mr/Pix

Phase Identification Detection Suspicion

Thermal

image

0.5mr/Pix

Phase Detection Suspicion

360° Image

1mr/Pix

Phase Detection Suspicion

Aucoustic

spectrogram

Image relative

size

A dynamic signature bank of known threats and non-threats is to be integrated into the

system. As the system is operationally deployed, this bank automatically expands and

enhanced by the system’s classification and learning algorithms. A shared repository

would let all authorised systems to be updated in real time or offline.




Page 8 of 20



At present, in order to establish a seed for this signatures bank, we have classified a few

dozen models of drones. The classification is based on basic characteristics of the drone

physical qualities, type of communication, navigation and command systems, range of

operation, etc. Here is a partial list of the classes used:

Command method: pre-programmed, online, hybrid, man in the loop, autonomous

Range: line of sight, BVR1, distance

Navigation system: None, Baro & Compass, GNSS2, INS3, Hybrid

Radio link: up-link, down-link, frequency, bandwidth, spectral signature, etc.

Video use: no camera, live use of video input onboard vs. at base station.

Homing system: man in the loop, autonomous, radio locked, video assisted, etc.

Propulsion system and thermal signature.

The different class correspond to different drone size and different ambient signatures,

hence to different means of detection and threat mitigation.

4. System’s Objectives and Design

4.1. Shielding Target Zones

Enforcing a no-fly-zone and shielded area varies with the nature of the target or event at

hand. At the lowest end, a small specific target over a small confinement, such as a

personal protection of a VIP on a political rally. Such a limited target system is of a

relatively low cost, tribute to the size of the shielded zone, limited features and the

possibility to provide the target some other extra means of complimentary protection.

Two main differentiators classify the different shielded zones and the means to protect

them: the size of the shielded area and the level of potential damage. As the protected

target gets bigger and the potential global damage is greater, e.g. a sport event or a

nuclear plant, the complexity of the required shielding system increases.

1 BVR – Beyond Vision Range

2 GNSS – Global Navigation Satellite System

3 INS – Inertial Navigation System




Page 9 of 20



Among other, here is a partial list of typical facilities needed to be protected:

Communication Infrastructure: Radio / TV / Phone broadcasting base stations, etc.

Energy Infrastructure: Power plants, Fuel reservoirs, etc.

State facilities and borders: Army camps, Jails, Hospitals, Courts, Borders, etc.

Events: Sport events, Open air concerts, Parades, etc.

4.2. System Structure

The basic features of the system are: modularity, scalability and hierarchically. All end

units are designed to communicate and co-operate directly and or through a local

command and control unit or via a global command centre. Thus, a bigger system is

easily assembled from a number of ready modules and sub-systems, incorporating sensor

units, communication units and command units. Whether and ad-hoc deployment of a

fixed installation, the system is fast to deploy, simple to maintain and bears low total cost

of ownership. It is ready to connect to the clients’ infrastructure via a connectivity module.

This design also ensures redundancy and high survivability of the system.

5. Preliminary Tests

Sample visual and thermal pictures of drones at various ranges were taken, acoustics

recording were analysed, and radio tracking of WiFi source was performed. The results

points out that there is no technological gap, and the expected results are listed in table 2

above.

5.1. Optical Detection

To achieve fast detection with low false alarm range a mix of visual and thermal cameras

is required. Wide FOV and narrow FOV cameras are required as shown in Fig 6.

Figure 6 – Visual & Thermal images of a drone




Page 10 of 20



5.3. SWIR Imaging

Using a SWIR camera with an eye safe laser at 1550 nano meter, as shown in figure 7

demonstrates the ability to detect reflecting objects at total darkness

Figure 7 – Processed SWIR image with illuminatiion




Page 11 of 20



5.4. Starring Cameras

Using of starring cameras allow relatively low cost coverage of large angles as

demonstrated in figure 8. In case that there is a need for high resolution, one may

use a high resolution sensor that are very expensive, or combine multiple low cost

cameras as demonstrated in figure 9.

Figure 8 – Starring cameras with large FOV




Page 12 of 20



Figure 9 - Multiple low cost cameras for high resolution coverage of large FOV




Page 13 of 20



5.5. Optical Tracking Example

Using staring cameras combined together in order to localize flying objects is a cost

effective method, while the cost of detectors by pixels drops each day.

Method Demonstration - Two IP cameras with 5 mega pixels sensors and upper

hemisphere coverage were mounted 1 m separated in order to be installed on a car, as

described in figure 10.

Figure 10 – Two aligned IP cameras separated 1 meter

Figure 11 describes the view of the two cameras with marking of the flying object

deviation from the centre of view, while figure 12 shows the schematic geometry.

Figure 11 – Two upper hemisphere images by two cameras separated 1 m




Page 14 of 20



Figure 12 – Top View of the cameras and the drone

5.6. Acoustic Detection

Drones’ propellers have a typical acoustic signature. Appropriate filtering can distinguish

between ambient noise and drone acoustic signature. Adding wind information will

improve the detection. Figure 13 demonstrates the spectrogram of a quadcopter together

with ambient noise.

Figure 13 – Acoustic Spectrogram of a Drone




Page 15 of 20



5.7. Radio Tracking

A 6 antennas radio signal tracking was used to track radio signal of a drone. The test

demonstrated the ability to find direction to a radio source with reasonable effort. The

required number of antennas and their locations will be determined to fit the expected

scenarios. Test results are shown in Figure 14.

Figure 14 – Preliminary radio tracking results

6. Threat Interception

The interception process starts in analyzing the drone broadcast and if possible analyzing

the operator’s broadcast. Once the broadcast protocols are identified, the possibility to

perform virtual interception by overtaking the drone up-link is examined and applied.

Drones’ interception is divided into categories according to the nature of the protected

area, according to the detected drone configuration, and the scenario. The main issue is

to maintain a high safety level according to the regulations. Meaning, it’s allowed to take

down drones only in dedicated killing zones. Interception outside the killing zones requires

capture of the drone and carrying it to the safe killing zone.

Hard-Kill Methods:

The threat is physically captured by a larger combat drone system. The combat drones

are spread in automatic launch nests, so they can reach the detected threat in short time.

The conventional war heads used for killing airborne targets is replaced by a capture

system that carries the threat to a safe zone. In specific events a standard killing method

is applied.




Page 16 of 20



We divide the Hard-Kill Method into the following cases:

A Standard weight which is about 2 Kg heavy – This drone will be captured by another

larger drone and carried to a safety zone.

A Heavy drone which is about 10 Kg heavy – This drone will be captured by the larger

drone and will be carried by an attached to a motorized parachute to a safety zone.

The intercept is time critical:

Short range interception at less than 200 m is performed by a combat drone

Medium range interception which ranges from 200 – 800 m is performed by a rocket

launched drone (With all flying objects attached to parachutes.

Ranges above 800 m are handled with standard antiaircraft methods

Hard Kill Intercept Timeline

The DFD is an SOS that is deployed at various levels. The current description is a single

drone nest, receiving its launch command from the DFD server. The different intercept

stages are described herein:

Nest Opening

The intercept drone is nested within its nest, a box, charged and ready for launch. Once

launch data and launch command received, the nest checks the local conditions: weather,

winds, and safety. It reports “Ready to Launch” and performs launch procedure.

Intercept Drone Launch

The drone is launched vertically and it accelerates toward the predicted intercept point. It

cruises at high speed and approaches the target pointing its camera toward the expected

intercept point.

End-Game – Camera Guidance

The End-Game starts when the target is detected by the camera and further identified.

The drone guides itself to the point where it’s effective to fire the net in order to hit or catch

the intruder. Figure 15 demonstrates direct hit test of a homing drone hitting a balloon.




Page 17 of 20



Figure 15 – Our Killer Drone chase and hit targets

Capture

The intercept drone is equipped with an automatically deployed capture net, which is

connected to it.

The drone deploys the net and captures the intruder.

Carry Away

The captured intruder drone is now carried by the drone to a safe disposal zone, where it

can be dumped or safely landed.

Typically, the plan is to use the drone as a carrier for the intruder. However, in case of

large intruders (drones) the drone will deploy a parawing, thus enabling to carry triple of its

carry capacity.




Page 18 of 20



Soft-Kill Methods:

Immediate intercept, fits in sterile areas, can be done: by jamming of the radio

channels of the drone, by another combat drone, firing, or energy weapon.

Diverting the drone to a sterile area by overtaking the up-link or spoofing the GPS.

Return home – Jamming the GPS will typically cause the drone to try to return home,

or to land immediately.

Controlled landing – to be performed by overtaking the up-link.

Taking over the command and control station – following detection of the drone, the

command station can be located and the drone mission will be aborted.

The spread drones’ nests system is the most cost effective solution to protect valuable

assets and events. It is deployed in short notice and it is ready to be deployed on ground

and maritime vehicles. Minimal nest holds one combat drone, while a larger nest holds a

battery of combat drones.




Page 19 of 20



7. Example of Shielding the Yankee Stadium in New York

Figure 16 demonstrates deployment of 3 detection stations of the DFD with visual and

radio capabilities to cover the stadium. The DFD allow lock on drone and interception

above the open park to minimize the peripheral damage.

Figure 16– Drone Free Dome shields Yankee Stadium

8. Live Demo

As far as we know there are no combat proven system deployed.

The detection and interception system integrates COTS products as well as custom made

elements. The main activity is the development of detection algorithms, data fusion

algorithms, target characteristic signatures, full coding of the software and system

integration. Following this parallel development GANTT it would be possible to achieve a

live demo shortly.




Page 20 of 20




Documents

Drones Free Dome (DFD) - Zickel Engineeringzickel.net/pdf/ZickelEngineeringDroneFreeDome... · 7/15/2017 · Zickel Engineering Consulting and Training LTD Tel: +972-4-8769229, Fax: