Citation: Qu, Z.; Willig, A. Sensorless
and Coordination-Free Lane
Switching on a Drone Road
Segment—A Simulation Study.
Drones 2022, 6, 411. https://doi.org/
10.3390/drones6120411
Academic Editors: Andrzej
Łukaszewicz, Wojciech Giernacki,
Zbigniew Kulesza, Jaroslaw Pytka
and Andriy Holovatyy
Received: 16 October 2022
Accepted: 10 December 2022
Published: 14 December 2022
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Article
Sensorless and Coordination-Free Lane Switching on a Drone
Road Segment—A Simulation Study
Zhouyu Qu
†,‡
and Andreas Willig *
,‡
Department of Computer Science and Software Engineering, University of Canterbury,
Christchurch 8140, New Zealand
* Correspondence: andreas.willig@canterbury.ac.nz
† Current address: Private Bag 4800, Christchurch 8140, New Zealand.
‡ These authors contributed equally to this work.
Abstract:
Copter-type UAVs (unmanned aerial vehicles) or drones are expected to become more and
more popular for deliveries of small goods in urban areas. One strategy to reduce the risks of drone
collisions is to constrain their movements to a drone road system as far as possible. In this paper, for
reasons of scalability, we assume that path-planning decisions for drones are not made centrally but
rather autonomously by each individual drone, based solely on position/speed/heading information
received from other drones through WiFi-based communications. We present a system model for
moving drones along a straight road segment or tube, in which the tube is partitioned into lanes.
We furthermore present a cost-based algorithm by which drones make lane-switching decisions,
and evaluate the performance of differently parameterized versions of this algorithm, highlighting
some of the involved tradeoffs. Our algorithm and results can serve as a baseline for more advanced
algorithms, for example, including more elaborate sensors.
Keywords:
drones; wireless communications; path planning; collision avoidance; performance
evaluation
1. Introduction
Unmanned aerial vehicles (UAV) or drones are increasingly becoming an interesting
alternative for the delivery of small goods, in particular in densely populated urban
environments [
1
–
3
]. Rotary-wing or copter-type drones are advantageous for this class of
applications due to their manoeuvrability, their ability to hover and their vertical take-off
and landing capability. Drone-based delivery has important advantages: (i) drones can
move in three dimensions and can often take a much more direct route than possible on a
street network, reducing the distance to travel and speeding up the delivery of time-critical
items; (ii) they are less likely to be hampered by traffic congestion and in turn, do not
contribute to the congestion of passenger-carrying vehicles on the ground; (iii) delivery
of small goods via drones is potentially more environmentally sustainable, as the mass
of a drone to be moved is orders of magnitude lower than the mass of cars or vans (even
though the drone additionally has to work against gravity) [
4
–
7
]. We expect that delivery
drones will become more autonomous and will be used in increasingly large numbers.
At the same time, flying drones present a safety hazard for humans, particularly when
a drone loses control and crashes, when two or more drones collide fatally, or when a
drone enters an airspace also occupied by manned aircraft (e.g., close to an airport or in the
operational area of a rescue helicopter). One approach to manage safety risks is to confine
drones to move along pre-planned airspaces most of the time. Therefore, we envisage the
introduction of a drone road system similar to a road network for vehicles, a network of
straight cylindrical segments (or tubes) meeting at intersections, which drones can enter
and leave either at pre-planned on- and offramps or at arbitrary locations. A drone road
Drones 2022, 6, 411. https://doi.org/10.3390/drones6120411 https://www.mdpi.com/journal/drones
