Table Of ContentResearch Topics in Aerospace
Johann C. Dauer Editor
Automated
Low-Altitude
Air Delivery
Towards Autonomous Cargo
Transportation with Drones
Research Topics in Aerospace
Series Editor
Rolf Henke, Mitglied des Vorstands, DLR, Cologne, Nordrhein-Westfalen,
Germany
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More information about this series at http://www.springer.com/series/8625
Johann C. Dauer
Editor
Automated Low-Altitude
Air Delivery
Towards Autonomous Cargo Transportation
with Drones
123
Editor
JohannC. Dauer
Institute of Flight Systems
German Aerospace Center
Braunschweig, Germany
ISSN 2194-8240 ISSN 2194-8259 (electronic)
Research Topicsin Aerospace
ISBN978-3-030-83143-1 ISBN978-3-030-83144-8 (eBook)
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Foreword
AutomatedLow-AltitudeAirDelivery:Thetitlealoneisunwieldy,andnowthereis
anentirebook about it.If DLRhad published a bookabout eachandevery oneof
its projects, it would have produced over 1,000 different books throughout its
history since 1907. So why publish a book on this topic and what makes it so
special?
The answers are simple: There are the technical challenges, then the social
aspects,andfinallyacomponentwhichIwouldliketocall“Zukunftssehnsucht”—a
yearning for the future.
Let us start with the story from a popular-science point of view: Unmanned
aircraft havebeenaroundforalongtime,andanotherspecialbranchofaviationis
alsocloselyconnectedwiththem:the“airtaxis”.Thesehavebeenpopularsincethe
“Jetsons” cartoons, are featured regularly in magazines such as “Popular
Mechanics” and appear time and again in sketches of visions of the future. It took
two elements from outside of civil transportation aviation to provide these topics
withanewimpetus.Firstly,consumerelectronicshavedemonstratedthatbyusing
inexpensivesensors,controllersandsoftware,stableflightattitudescanbeachieved
evenforsimpledevices.Secondly,militaryaviationhasalsodevelopedapplication
possibilities outside of armed missions, such as monitoring/observation and
heavy-goods transport.
In the 2010s, a new aspect was added: Once the delivery of goods via Internet
orders had been extensively automated, it would only be a matter of time before
both large Internet companies and start-ups began to address the “last mile”. The
first video from the “Prime Air” segment of a major Internet provider in October
2015becamelegendary,andsincethen,thetopichasbeendiscussedintensively—
from the fast transport of organs to the “pizza helicopter”.
This all provided the ingredients which led to the status in 2020: Automatic
freighttransportis“withinreach”,andevenairtaxisare“envogue”again.Freight
transportbeginsatjustafewgramsforcameras.Foramajorresearchfacilitysuch
as DLR in general, and for the transport class described in this book in particular,
payloads in the range of several hundred kilos are addressed; the smaller ones are
v
vi Foreword
still left to existing companies, and the larger ones fall into the category of cargo
aircraft.
The start-ups mentioned exert a great deal of pressure on the air transport sys-
tem, which,in myopinion, isvery good for it. Fortoo long, passenger and freight
transport by air has been visible only in one way, which has led to a certain
saturation of the mind. It is now necessary to think about new concepts and to
questiontheexisting,classicmodes.Theoverallsystemisfacingnew,overarching
challenges—not only for the vehicle but also for the airspace.
Inthe case of air taxis, new and interesting alliances haveformedalongsidethe
start-ups (but some of them have already dispersed again—an indication of the
dynamicsofthesystem):AirbusandAudi,BoeingandPorsche,HyundaiandUber.
It isapparentthat,foronething,completelynew types ofaircraft areseekingtheir
place in the system, and that, for another, new business models will also charac-
terize this “new aviation”.
DLR has always had unmanned aircraft in operation, and institutes such as
Flight Systems, Robotics and Sensor Systems Technology are scientifically
engagedinthisfield.Associety’sinterestinthesevehiclesgrew,itbecameobvious
that we would have to address this topic more intensively.
DLR’s aeronautics research strategy aims to ensure an evaluation capability
throughouttheentireaeronauticssystem;wewanttobeabletoprovidemeaningful
information on components, vehicles, processes and effects, with proven, reliable
accuracy,viamodels,simulationandexperiments.Inordertosharpenourtoolsfor
this, we defined six guiding concepts in 2013, whereby individual topics from
variousinstitutesareraisedtoahigherlevelofintegration.Until2019,oneofthese
guidingconceptswas“UnmannedFreightTransport”,whichcorrespondstotheera
of the ALAADy project. In the meantime, we have expanded this guiding concept
to “Urban Air Mobility”, in order to take into account the current social relevance
ofthetopic.ThetopicsaddressedbyALAADywill,ofcourse,continuetobetaken
into consideration.
ThreenewDLRfacilitieswillcontributetothesuccessoftheALAADyprogram
in the future:
(cid:129) In 2019, DLR founded its “National Experimental Test Center for Unmanned
Aircraft Systems” in Cochstedt near Magdeburg. The Center covers an exten-
sive area of land andenables research intoallpractical aspects, including those
relatingtofutureinfrastructures.ThisiswheretheALAADydemonstratormade
itsmaidenflight,andthisiswherewewillcontinuetotestthistypeofvehiclein
the future—whether developed at DLR or by partners.
(cid:129) Furthermore, in2020,DLRfoundedits“SmallAircraftTechnology”facilityin
Aachen,whichwillbesetupduringtheALAADytrials.Thetopicsplannedfor
this facility, such as the design, production, propulsion, maintenance of small
aircraft in the form of the ALAADy demonstrator or air taxis, will pursue the
continuation and implementation of the results obtained through ALAADy.
Foreword vii
(cid:129) And finally, at the Institute of “System Architectures in Aeronautics”, founded
in 2017, the entire system can be analyzed. Not only the vehicle but also its
operationinagivensystemovertheentirelifecycleisrelevant.Forthisreason,
new architectures must be developed which deviate significantly from the
classic airport-airspace concept of today’s transport aircraft.
In addition to these three completely new facilities, the scientific focus of the
ALAADy project in recent years has been achieved through many “classical”,
experienced and proven aviation institutes and their expertise, above all the insti-
tutesfor“FlightSystems”and“FlightGuidance”.Oneinstitutealonecouldaddress
solelytheindividualaspects,e.g.,thevehicle,theairspaceorthelogisticsinitsfield
of activity. By combining the capabilities of all the institutes through DLR’s
aeronauticsprogram,comprehensivesolutionsare,however,createdwhichsupport
the industry in terms of products and the politicians in their decisions.
One goal of the ALAADy project was the construction of a demonstrator, a
low-flying freighter with a payload capacity of several hundred kilos. Despite the
factthataproductsuchasthe“ALAADyDemonstrator”cannotbebought,itwas,
in addition to considerations concerning airspace and logistics, imperative to
acquireafreelyavailableproductfromtheworldofmannedaviationandtoconvert
itintoanunmannedaircraft.Thelearningeffectinsuchacaseisparticularlystrong:
Foreverysinglecomponent,itisnecessarytoconsiderwhatmustbeavailableand
with what reliability. All sensors and actuators, existing and additional, which are
required as a result of the now absent pilot, must be subjected to a critical exam-
ination in order to be utilized in unmanned operations. All this is carried out on
almostunknownterrain,asthecorrespondingapprovalregulationsdonotyetexist.
As a consequence, however, this procedure is future-oriented for DLR as well:
Otherbodiescanalsobenefitfromsuchafuture“constructionmanual”.Asamatter
offact, the institute performingtheprojectreceivednumerousenquiries duringthe
development phase, and a business model can certainly be expected in the coming
years.
Equally challenging was and is the investigation of the movement of such an
unmanned device through the general airspace. This concerns the immediate sur-
roundings in the sense of the requirement for pilots to avoid collisions: “see and
avoid”,whichmustnowbecome“senseandavoid”.Accordingly,thequestionasto
the rules under which large numbers of unmanned devices should operate, both in
their interaction with each other and in the choice of suitable flight paths, taking
into account all other traffic participants such as rescue helicopters or general
aviation, is of paramount importance. Two major DLR projects have hereby pro-
vided valuable contributions and have attracted worldwideattention: Inthe project
“UnmannedFreightOperationsUFO”,transportvialargeAirbus-classaircraftwas
investigated, resulting in the derivation of rules for smaller vehicles for ALAADy.
And one of DLR’s most significant projects on the topic of “Urban Air Mobility”,
the “City ATM” project, extends the airspace integration of ALAADy to include
operation over urban areas.
viii Foreword
As one of the very few research centers in the world, DLR is able to analyze,
simulateandoptimizeboththeindividualvehiclesandtheirutilizationinaholistic
manner. For selected points, universities or other research centers in Europe also
achieve success, but only the breadth and depth of DLR’s expertise can result in
usable concepts for low-altitude cargo delivery, i.e., ALAADy.
Whilethisprefaceisbeingwritten,the“ALAADyDemonstrator”isundergoing
flighttestingatthenewDLRtestcenterinCochstedt.Simultaneously,theplanning
for further demonstrators—and, consequently, other projects within DLR and also
with partners inGermany and Europe—isbeing carried out inthefascinating field
of unmanned aircraft in all their diversity.
At the same time, work is being undertaken in Europe and internationally on
certificationrules,whichDLRwillhelptodefine.Inadditiontonewregulationsfor
the vehicle and its movement in the airspace, new certification rules are also
required for innovative—often electric—propulsion systems. In the case of the
ALAADy Demonstrator, the propulsion system is still “classic”, but we will also
use this knowledge and share it with the authorities in order to forge ahead in the
broader context of unmanned small aircraft.
I hope that this book about ALAADy will be a rewarding experience for all
readers. The authors and supporters deserve my sincere thanks; it takes a tremen-
dousamountofworkandcommitment notonly todeliver aproject reportbutalso
toscientificallyanalyzethistopicfromtheverybeginning.ALAADywas“only”a
projectinDLRaviationresearch,butitisalsoasynonymforourworkingprinciple:
interdisciplinary, holistic, comprehensive, with thematic breadth, high standards
and scientific depth in the support of research, industry and politics.
August 2020 Rolf Henke
Preface
This book presents the condensed results of the project Automated Low Altitude
AirDelivery(ALAADy)oncargodeliverywithunmannedaircraftdevelopedatthe
GermanAerospaceCenter(DLR).Wesummarizethefindingsoftheyears2016to
2019. Payload capacities of one metric ton are considered. At the same time, it is
investigated if the operational risks for such comparably large aircraft can be
reduced to a point where a design for the operation within the EASA specific
categoryisjustified.Theriskssuchunmannedaircraftposetotheenvironmentare
minimized by flying below general air traffic and exclusively over sparsely popu-
latedareas.Besidecontributingtoandovercomingmanytechnicalchallenges, this
work serves two major goals. First, the EASA specific category is challenged to
identify possible limitations in size and operational conditions. Second, a safety
benchmarkiscreatedtoserveasatestfortheAcceptableMeansofCompliancefor
this operational category.
The book is divided into four parts. Part I establishes the basis of the project,
whichprovidesareferenceforthefollowingpartsofthebook.Thesefundamentals
includeapplyingthemethodstoconsidertheoperationalriskinthedevelopmentof
new unmanned aircraft. Additionally, the potential use-cases and economic per-
spectives are discussed. Part II of the book examines the aspects of the aircraft
configuration.Thefocusisontheimpactoftheoperational-risk-basedmethodson
theaircraftitself.PartIIIisdedicatedtothecomponentsandmethodstoenablesafe
autonomy. The focus includes airspace integration, detect and avoid, onboard
system architecture, route planning, runtime monitoring and datalinks. PART IV
of the book presents the verification and validation of the study. It summarizes
different forms of simulations and several technology demonstrations.
The first chapter of the book introduces the goals of the ALAADy program in
detail and spans the various research questions that arise. The following chapters
are each dedicated to answer individual questions based on each technical disci-
pline. The final chapter of the book brings together the results from the different
research activities and provides an overall perspective of the findings.
ix
