The miniaturization of sensor payloads has been a task for
some time now; however, it has been limited as to how many sensors are capable
of being compacted to fit in such a small space. Powerful and accurate sensors
in the past tended to be very large and expensive, dictating that they be
carried by platforms of similar size (Watts, Ambrosia & Hinkley, 2012). They
are however, too large to fit smaller Tier 1 and II classes of Unmanned Aircraft
Systems.
With today’s technology, we can achieve vastly powerful sensors with decreases
in size, weight and power consumption. As platforms get smaller, so to do the
sensors that are capable of being paired with them. The commercial market has for
years benefited from reducing the size of electronic components (Patterson
& Brescia, 2008). One good example is a piece of technology that mostly all
humans have come to rely on daily, called cell phones! The UAS industry is by
far one of the newest users to take advantage of this miniaturization age! It has
led to the ability to provide multiple sensor operations from a single Unmanned
Aircraft System” (Patterson & Brescia, 2008). Commercial companies will continue
to gain momentum towards miniaturization of existing technologies for UAS
Sensor Payloads, highlighting that it is the sensors payloads themselves that
will see the most advancement in the next 5-10 years.
Figure 1:
Smaller Sensor Payloads. Adapted from “Octopus ISR Reveals World’s Smalles
Four-Sensor MWIR Gimbal,” by Unmanned System Technologies, 2017, retrieved from
http://www.unmannedsystemstechnology.com/2017/05/octopus-isr-reveals-worlds-smallest-four-sensor-mwir-gimbal/
This year, Octopus ISR Systems lead the charge in designing
and developing the next-generation of gimbal payloads. What is unique about
this gimbal payload is that it is the world’s smallest, most capable sensor weighing
in at 5.7 pounds (Unmanned System Technology, 2017). It houses not only one,
but four different types of sensors. Additionally, the gimbal payload is gyro-stabilized
and can move about in a 3-axis configuration (Unmanned System Technology, 2017).
Its official name is the Epsilon 175 and it was invented for the UAS market
that weighs under 55 pounds (Unmanned System Technology, 2017). It undoubtedly unlocks
new capabilities for these UASs that are traditionally constrained by the size
and weight of previous four-sensor gimbal payloads. Its four sensors are
comprised of an electro-optical camera with 30x zoom, a medium wavelength
cameras capable 15x zoom, a laser range finder and a laser illuminator
(Unmanned Systems Technology, 2017). Truly an amazing package of technology
that could be employed for border control operations, even tactical military
uses and other civil applications (Unmanned System Technology, 2017).
References:
Patterson, M. C. L. & Brescia, A. (2008). Integrated
Sensor Systems for UAS. Retrieved from http://www.dtic.mil/dtic/tr/fulltext/u2/a503447.pdf
Unmanned Systems Technology. (2017). Octopus ISR Reveals
World’s Smallest Four-Sensor MWIR Gimbal. Retrieved from http://www.unmannedsystemstechnology.com/2017/05/octopus-isr-reveals-worlds-smallest-four-sensor-mwir-gimbal/
Watts, A. C., Ambrosia, V. G., & Hinkley, E. A. (2012). Unmanned
Aircraft Systems in Remote Sensing and Scientific Research: Classification and
Considerations of Use. Retrieved from https://www.e-education.psu.edu/geog892/sites/www.e-education.psu.edu.geog892/files/images/lesson01/
remotesensing-04-01671.pdf
Responding to
disasters is a critical function for first responders and emergency management.
(Price, 2016) “Whether conducting a search and rescue operation for a lost
hiker or assisting public agencies during a major flood event, drones can play
an essential role during emergency response” (NCDOT, 2017).
In Price’s
article titled “UAS for Emergency Management” (2016) he talks about how the advancement
of UAS technology has created a ripe environment for the necessary transformation
of disaster and emergency first response activities. Application of UAS for
these efforts range from recovery, relief, and mission person searches to
damage assessments (Price, 2016). Overseas, UAS have been influential in enabling
quick and safe responses to the Fukushima nuclear accident and the Haiyan
Typhoon in the Philippines (Aasand, 2015). However here in the US, UAS have yet
to reach their full potential due to a slew of issues, but most notably NAS access
(Price, 2016). “The
timeframe required to obtain a COA is mission prohibitive for real-time
response to disasters and presents a significant barrier to agencies that may
be interested in using UASs for immediate disaster response missions” (Price,
2016).One state this year decided to do something
about that! The North Carolina Department of Transportation established best
practices and recommended policies to support immediate, safe integration of UASs
into the NAS (Lillian, 2017). These policies set in motion a safe and effective
way to aid first responders and emergency management personnel in executing
disaster and emergency operations. It is clear that if such barriers can be
removed, the true benefits of using UASs (to save lives) can be realized.
There
are several advantages for using an UAS when compared to manned aircraft
ranging from risk reduction, cost, operation, and persistence. Disaster and
emergency responses can incur high levels of risks for manned aircraft (Aasand,
2015). While UASs on the other, substantially lowers that risk because aircrews
are removed from imminent dangers posed by the disaster or emergency situation
at hand (Barnard, 2009 & Lillian, 2017). Furthermore, UASs are fairly
inexpensive, and the cost per hour (associated with maintenance and fuel) is
less than 20% when compared to manned aircraft (Barnard, 2009). As for UAS operations,
they provide quicker response times by deploying from virtually anywhere day or
night, can navigate unreachable locations more easily and at lower altitudes,
for example: dangerous terrain or in areas were toxic, radioactive or unknown gases
would otherwise risk human life to navigate (Barnard, 2009; Price 2016 &
Lillian, 2017)! Additionally, UAS can be re-tasked at a moment’s notice because
the command & control center is co-located with the operator. This is
important because information is the essence of the C2 node. By combing that
capability with the UAS, it offers a more centralized and coordinated approach.
As for payloads, it can be operation dependent and depending on the design of
the UAS, it can be a very easy process to tailor payloads to the situation (Price,
2016). UASs make the process of disaster and emergency management operations easier, tailorable, persistent
over longer distances, and safe.
References:
Aasand,
E. 2015. American Red Cross, Measure study UAVs for
disaster relief. Retrieved
from http://www.uasmagazine.com/articles/1079/american-red-cross-measure-study-uavs-for-disaster-relief
Barnard,
J. 2009. Unmanned Aircraft for Disaster Management. Retrieved from https://artes-apps.esa.int/sites/default/files/8.%20Barnard_%20UA%20in%20Disaster%20Management%20OUTPUT%20V2.pdf
Lillian,
B. 2017. North Carolina DOT Comes up with Best Practices for UAS in First
Response. Retrieved from http://unmanned-aerial.com/north-carolina-dot-comes-best-practices-uas-first-response
North
Carolina Department of Transportation (NCDOT). 2017. NCDOT Establishes Best
Practices for Drone Use in Disaster Response. Retrieved from https://apps.ncdot.gov/newsreleases/details.aspx?r=13630
Price,
D. 2016. Unmanned Aircraft Systems for Emergency Management. Retrieved from https://www.domesticpreparedness.com/resilience/unmanned-aircraft-systems-for-emergency-management/
See and
avoid is a concept to abate aircraft collisions. Integration of air traffic, in
different classes of airspace and operating under different rules, rely on it
to provide a safe flight environment. It is preferred that Unmanned Aircraft Systems (UAS) have the same
ability when it comes to see and avoid; however, it is supplemented with the
phrases detect or sense, and avoid. Information that governs see
and avoid (SAA) are found in the 14 Code of Federal Regulations (CFR) and numerous
products produced by the FAA and organizations like: Radio Technical Conference
of Aeronautics (RTCA). These standards are applied to UAS because they need to satisfy
the same standards as manned aircraft for proper integration
Regulations
The 14
CFR, Federal Aviation Administration Regulation, Parts 91.111, 91.113 and
91.115 (water) represent the main guidance for Sense and Avoid (Electronic Code of Federal
Regulations, 2017). Specifically, Part 91.113 states that “When weather conditions permit,
regardless of whether an operation is conducted under instrument flight rules
or visual flight rules, vigilance shall be maintained by each person operating
an aircraft so as to see and avoid other aircraft. When a rule of this section
gives another aircraft the right-of-way, the pilot shall give way to that
aircraft and may not pass over, under, or ahead of it unless well clear"
(Skybrary, 2016).Right of way rules are a set of standards or prescribed
maneuvers that aid the pilot in executing the safest and most effective method
to avoid a collision. They are defined according to certain categories of
operation and are used to justify giving way to slower moving objects in the
aerospace environment. These protocols are standard operating procedures for
all pilots. The Radio Technical Conference of Aeronautics (RTCA) defined UAS
see and avoid as:“The ability of a pilot to see traffic which may be a
conflict, evaluate flight paths, determine traffic right-of-way, and maneuver
to avoid the traffic” (FAA, 2009). Guidance for UAS operating in the NAS is given in FAA Order
7610.4K with the intention that UAS operations provide an equivalent level of
safety to that intended by Title 14 CFR Part 91 requirements for manned
aircraft SAA (FAA, 2009).
Layered Defense to Collision Avoidance
See and
avoid is all but one of the methods used to de-conflict traffic from sparse to
high-density air traffic environments, with others being procedural control, specific
vectors or traffic advisories from a controlling agency’s radar depending on
airspace class and position reports from the aircraft themselves (avoidance for
non-cooperative traffic), and notifications from traffic avoidance systems that
like users have from TAS, to TCAS and ADS-B (defined as cooperative traffic) (Bergqvist,
2017, NASA Access 5, 2008, Rosenkrang, 2008, &Skybrary, 2016).
Figure
1: UAS Safety Layers Under Study for Collision Avoidance. Rosenkrang, Wayne.
2008. Flight Tech: Detect, Sense and Avoid. Aviation Safety World Magazine.
Retrieved from http://flightsafety.org/asw/july08/asw_july08_p34-39.pdf?dl=1
Currently,
see and avoid is the last line of defense in a layered approach to prevent a
collision. Sometimes, it is used in coordination with the previously mentioned methods
to confirm if and when a maneuver needs to be executed. Depending on the rate
of closure and position of the converging aircraft, that maneuver can be very
time-sensitive and aggressive in execution, especially when prior notification
is not available (from systems, pilots or controllers) and visual acquisition of
the converging aircraft occurs late. Even though technology has matured
enough to execute avoidance maneuvers in the layers before see and avoid needs
to be executed, in manned aircraft it still remains a viable method in case those other layers
fail (TAS, TCAS or ADS-B).
Figure 2:
Traffic Separation Layers. NASA Access 5. 2008. Collision Avoidance Functional
Requirements for Step 1. Retrieved from https://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/20080017111.pdf
Current & Future Implementation of DSA Technology
For Collision Avoidance
Current testing has centered on using manned aircraft and Next Gen technologies to execute Detect/Sense and Avoid (DSA) actions. Detection
and sensing is more appropriate for UAS operations because sensors will need to
denote if something is there and if it presents a threat, either to a remote
pilot or the autopilot in a fully automated UAS (FAA, 2009). Non-cooperative
traffic detection aims to replace the pilot seeing a traffic conflict, while cooperative sensors provide
an additional capability (NASA Access 5, 2008 & Rosenkrang, 2008). Together, the combination of systems are comprised of radar, TCAS and ADS-B
these sensors represent active systems to detect cooperative and
non-cooperative traffic (FAA, 2009). These sensors already have certification
from the FAA, which will speed up the process for NAS integration.
Future systems
and specifically, smaller UASs, may see an emergence of more passive systems
like electro-optical and infrared devices to define the presence of
uncooperative traffic in lieu of radar (FAA, 2009). While early DSA efforts
focused on single systems, more recent efforts have focused onmultiple
sensor that are capable of cooperative and uncooperative detection/sensing.
This synergy provides a fuller spectrum to cover gaps and provide a redundant/cross-referencing
capability for some attributes of DSA, see Figure 3 (FAA, 2009).
Figure 3: Technology Attributes for DSA FAA. 2009. Literature
Review on Detect, Sense, and Avoid Technology for Unmanned Aircraft Systems.
Retrieved from http://www.tc.faa.gov/its/worldpac/techrpt/ar0841.pdf
It will represent
the new norm for medium and high-altitude long endurance UASs, but small UASs
might not be able to carry the same amount or type equipment due to its smaller
size and lower power generation (FAA, 2009). Thus, a solution for small UASs
might be to remove the system from the UAS itself and provide more technologies
(applications in GCS, ground radar or other methods) that are capable of facilitating
collision avoidance to meet the detect/sense and avoid requirement. Active
systems that can be further miniaturized (like ADS-B) provide an additional
alternative or additive capability (FAA, 2009). Utilizing ground systems (radar
and cellular towers) and ADS-B is NASA’s focus for testing and providing a
complete UAS Traffic Management (UTM) system (NASA, 2017).
References:
Electronic
Code of Federal Regulations. 2017. Title 14, Chapter I, Subchapter F, Part 91 –
General Operating and Flight Rules. Government Publishing Office. Retrieved
from https://www.ecfr.gov/cgi-bin/text-idx?c=ecfr&sid=3efaad1b0a259d4e48f1150a34d1aa77&rgn=div5&view=text&node
=14:2.0.1.3.10&idno=14
FAA.
2009. Literature Review on Detect, Sense, and Avoid Technology for Unmanned
Aircraft Systems. Retrieved from http://www.tc.faa.gov/its/worldpac/techrpt/ar0841.pdf
NASA
Access 5. 2008. Collision Avoidance Functional Requirements for Step 1. Retrieved
from https://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/20080017111.pdf
NASA.
2017. Unmanned Aircraft System (UAS) Traffic Management (UTM). Retrieved from https://utm.arc.nasa.gov/index.shtml
Rosenkrang,
Wayne. 2008. Flight Tech: Detect, Sense and Avoid. Aviation Safety World
Magazine. Retrieved from http://flightsafety.org/asw/july08/asw_july08_p34-39.pdf?dl=1
Skybrary.
2016. See and Avoid. Retrieved from http://www.skybrary.aero/index.php/See_and_Avoid
Comparing Military UAS Missions
to Similar Civil UAS Missions
The
development of Unmanned Aircraft Systems (UAS) has revolutionized the way we
think about and employ aerospace vehicles to improve our daily lives, support
our security and protection, and conduct wars. Different types of mission sets
are possible because of the varying sizes or classes of UASs that have been
developed and mostly due in part to the fact the human has been removed from
the equation. This in turn allows room for payloads and allows the engineer to
design a platform that if big and efficient enough, can stay aloft for long
periods of time.
Voice and
data communications is one area that continues to be improved constantly. Terrestrial
and space-based systems are the preferred methods for ensuring access to this type
of technology but has its challenges and limitations. The military relies
heavily upon communications to execute its various missions today. However,
terrestrial systems are not well suited for providing communication to a highly
mobile ground force and spaced based systems are becoming crowded due to
competing needs and the military simply does not own enough organic systems
which constitutes a reliance on civilian space assets.
Military UASs That Enhance
Communication
The
introduction of UAS systems like the EQ-4B has provided the military with a mission
set that allows voice and data transmissions and is dubbed the Battlefield
Airborne Communication Node (or BACN) (Northrop Grumman, 2017). The EQ-4B BACN mission
enables a persistent gateway in the sky that receives, bridges and distributes
communication for all participants in a battle” (Northrop Grumman, 2017).More specifically, the EQ-4B BACN
enables communication among tactical data links in aircraft and ground forces that
might not be interoperable, enables joint range extension, BLOS connectivity
for disadvantaged LOS users and IP-based data exchange among dissimilar users
(Northrop Grumman, 2017). Some might think of it as a cell phone tower combined
with a satellite in the sky (Miller, 2015)! Another military application is the
AAI Shadow Tactical UAS, which is equipped with the Forward Airborne Secure
Transmissions and Communication (FASTCOM) system (Textron News Release, 2011).
It can provide a secure, mobile cellular network for up to 100 users simultaneously
to enable voice, data and imagery communication, satellite communication
connectivity among multiple users and backhaul across the battlefield (Textron
News Release, 2011). As with all military applications, they can easily be
translated into a civil application.
Civilian Missions That Seek to Enhance
Communication
A mature civil
application that is similar to the EQ-4B BACN is still in its infancy.
AT&T is currently testing an UAS called cell on wings (or COW), and has
been operating for a year (UAS Weekly, 2017). It is designed to enhance
coverage in notorious troublesome areas of reception to extend cellular
coverage like a stationary cell tower does (UAS Weekly, 2017). Additionally,
the UAS captures data from network sites to feed to AT&T systems and a new
round of testing, in coordination with intel, will determine the feasibility of
using LTE-connected drones to provide better wireless service at large venues (UAS
Weekly, 2017). Another civilian application is Titan Aerospace’s high-altitude,
solar-powered drone that aims to deliver internet service to underserved areas (O’Toole,
2014). While Titan’s drones are not
commercially available, the concept has been tested in demonstration flights (O’Toole,
2014).
Strengths and Weaknesses
The military
UAS applications like the EQ-4B BACN and the AAI Shadow are two of the most
advanced airborne UAS communication nodes. They provide a multiple of services
from one platform that can meet the needs of multiple users and multiple types
of networks.
The weaknesses
with virtually all airborne platforms is their endurance or ability to stay
aloft. Specifically, for these UAS communication nodes you have to compare it to
terrestrial or space-based systems that are designed to function for longer
periods of time and are maintained (terrestrial) or replaced at certain
intervals (space-based). The global hawk provides 30 hours of coverage, while
the AAI Shadow only has an endurance of. The AT&T small UAS will undoubtedly
have the lowest endurance just due to its small design but the Titan Aerospace
high-altitude drone is expected to stay aloft for 5 years (O’Toole, 2014). Not
all of these systems will do the exact same mission set because they were
designed for customers with different requirements but they do have some
similarities and overall will serve as some type of communication node for a
ground customer.
Future of UAS as Communication Nodes
The future
application for UAS based communication nodes that are capable of providing voice
and data communication is bright. Military applications are most certainly
leading the effort and will continue to be a part of ensuring war fighting
elements are connected for a common air picture. The future for military
applications might see it not only applied to all UASs, but every single
aircraft and ground based vehicle to provide a robust and redundant network.
For civilian
applications, ensuring that dead spots and other degraded areas of coverage receive
reliable voice and data services is game-changing for those long car rides
through places like Eastern New Mexico where coverage may be limited due to lack
of infrastructure (UAS Weekly, 2017). As well as bringing voice and data
services to countries that do not have a terrestrial network or is not covered
by satellite communication services. Additionally, an aero-communication node
could function as a backup or booster to satellites when services are degraded
by electro-magnetic interference from space or severe scintillation from atmospheric
events.
References:
Friedrich,
George. 2014. Applications of military and non-military Unmanned Aircraft
Systems (UAV). Retrieved from http://www.academia.edu/11154604/Applications _of_military_and_non-military_Unmanned_Aircraft_Systems_UAV_
Miller, Frank.
2015. Global Hawk reaches new milestone, helps in fight against ISIS. Retrieved
from http://www.af.mil/News/ArticleDisplay/tabid/223/Article/628873/
global-hawk-reaches-new-milestone-helps-in-fight-against-isil.aspx
O’Toole, J.
2014. Google buys drone maker Titan Aerospace. CNN Tech. Retrieved from http://money.cnn.com/2014/04/14/technology/innovation/google-titan-drone/index.html
Textron News
Release. 2011. AAI, OVERWATCH AND VIASAT TO SHOWCASE FASTCOM™ AT EMPIRE
CHALLENGE 11. Retrieved from http://investor.textron.com/news/news-releases/press-release-details/2011/AAI-Overwatch-and-ViaSat-to-Showcase-FASTCOMTM-at-Empire-Challenge-11/default.aspx
UAS Weekly.
2017. AT&T Testing ‘Flying COW’ UAS To Enhance Cell Coverage. Retrieved
from http://uasweekly.com/2017/02/22/att-testing-flying-cow-uas-enhance-cell-coverage/
