The animated version of these slides is available UTM in ......Centralized and Distributed UTM in...

Centralized and Distributed UTM in Layered Airspace

Leonid Sedov, Valentin PolishchukLinköping University

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The animated version of these slides is available online - https://tinyurl.com/icrat18utm

1. Introduction and motivation

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ATM realityPre-planned airport-to-airport flights

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UTM designer dream (NASA, Ectl ConOps) = ATM reality

● All know all● Centralized system● Flightplans submitted● Conflicts checked● Conflicting flightplans delayed

(Ground Delay Program)

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UTM designer dream (NASA, Ectl ConOps) = ATM reality

● All know all● Centralized system● Flightplans submitted● Conflicts checked● Conflicting flightplans delayed

(Ground Delay Program)

COMMon UNmanned Integrated System

Management

COMMUNISM 5

UTM ≠ ATM

Model Boeing 747-400 DJ Phantom 4

Max # of passengers 660 0

Speed 982 km/h 72 km/h

Weight 184.567 kg 1,4 kg

Length x Width x Height 70,60 m x 64,44 m x 19,41 m 0,32m x 0,38 m x 0,22 m

Requires runway 6

Drone aerodromes

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Flexibility where possible, structure where necessary

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2. Airspace designs

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Single-layer design

All drones occupy the same altitude

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Ground Delay12

The animated version of this slide is available online - https://tinyurl.com/icrat18utm

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Ground Delay

The animated version of this slide is available online - https://tinyurl.com/icrat18utm

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Ground Delay

The animated version of this slide is available online - https://tinyurl.com/icrat18utm

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Airborn delay (hovering)

The animated version of this slide is available online - https://tinyurl.com/icrat18utm

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Airborn delay (hovering)

The animated version of this slide is available online - https://tinyurl.com/icrat18utm

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Airborn delay (hovering)

The animated version of this slide is available online - https://tinyurl.com/icrat18utm

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Airborn delay (hovering)

The animated version of this slide is available online - https://tinyurl.com/icrat18utm

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Multi-layer design

20Something similar to “Layers” in Metropolis project ↑

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Layer assignment

The animated version of this slide is available online - https://tinyurl.com/icrat18utm

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Layer assignment

The animated version of this slide is available online - https://tinyurl.com/icrat18utm

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Layer assignment

The animated version of this slide is available online - https://tinyurl.com/icrat18utm

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Descending

The animated version of this slide is available online - https://tinyurl.com/icrat18utm

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Descending

The animated version of this slide is available online - https://tinyurl.com/icrat18utm

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Descending

The animated version of this slide is available online - https://tinyurl.com/icrat18utm

Conflict resolution algorithms

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Single-layer Multi-layer

Centralized Ground delay Layer assignment

Distributed Hovering On-demand descending

Single- vs Multi-layer

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Single-layer design Multi-layer design

Limited need in airspace The airspace is limited

Loss of efficiency No loss of efficiency

3. Simulation

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InstantiationCal model

● [Bulusu, Sengupta, Liu (Berkeley) @ ICRAT'16] ● [PK (NASA's UTM PI) @ Google:

"every home will have a drone and every home will serve as an aerodrome"]

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Population density

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UAV = disk

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Ground Delay: Direct flight

3333Figure 3 from [Bulusu, Sengupta, Liu (Berkeley) @ ICRAT'16]

Hovering

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Layer assignment

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Layer assignment == Graph coloring

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Nodes = UAVsEdges = conflictsColors = layers

Descending

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Input● Population density map● Expected number of flights N● Radius r of UAV

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4. Results

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Average extension of travel time

Decentralized (hovering)Centralized (ground delay)40

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Ground Delay

Percentage of UAVs lost > 10% of time

Centralized (ground delay) Decentralized (hovering) 42

Delay probability

Almost the same for hovering

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Number of layers used

Centralized (layer assignment) Decentralized (descending) 44

Distribution of drones

Centralized (layer assignment) Decentralized (descending)45

% of UAVs in a vertical collision, hovering

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% of UAVs in a vertical collision, layer assignment

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% in a vertical collision, on-demand descending

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+ the same collisions as in layer assignment

What if we distribute drones among layers based on heading direction?

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5. Conclusion and further work

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ConclusionIs centralized always better?

Understand UTM automation levelHow central should UTM be?

Mantras

● Flexibility where possible, structure where necessary [PK et al, NASA ConOps]

● When technology is right, regulation is light [F. Schubert, Skyguide CCO]

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Further work● Limit the number of layers● Other coloring

○ Sum coloring○ Balanced coloring○ Equitable coloring

● Other deconfliction strategies

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Further work● Limit the number of layers● Other coloring

○ Sum coloring○ Balanced coloring○ Equitable coloring

● Other deconfliction strategies

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