Contents lists available at ScienceDirect Journal of Industrial Information Integration journal homepage: www.elsevier.com/locate/jii Swarms of Unmanned Aerial Vehicles — A Survey Anam Tahir a, ⁎ , Jari Böling b , Mohammad-Hashem Haghbayan a , Hannu T. Toivonen b , Juha Plosila a a University of Turku, Finland b Åbo Akademi University, Finland ARTICLEINFO Keywords: Swarm of drones Swarm of Unmanned Aerial Vehicles ABSTRACT The unmanned aerial vehicles or drones come in a great diversity depending upon the basic frameworks with their particular specifications. The purpose of this study is to analyse the core characteristics of the swarming drones and measure the public awareness levels with respect to these swarms. To achieve these goals, the functionality, problems, and importance of drones are highlighted. The results of an experimental survey from a bunch of academic population are also presented, which demonstrate that the swarms of drones are fundamental future agenda and will be adopted with the passage of time. 1. Introduction A swarm or fleet of Unmanned Aerial Vehicles (UAVs) is a set of aerial robots i.e., drones that work together to achieve a specific goal. Each drone in a swarm is propelled by a specific number of rotors and has the ability to vertically hover, take-off, and land (VTOL). The flight of the drones is controlled either manually, i.e. by remote con- trol operations, or autonomously by using processors deployed on the drones [1]. A common purpose for drones is a military one, but their civilian applications are attracting increased attention in the recent time. Indeed, low-cost drones and their swarms provide a promising platform for innovative research projects and future commercial ap- plications that will help people in their work and everyday lives. Swarms of drones can be classified in different ways. For example, Fig. 1 illustrates fully and partly (semi) autonomous swarms. From another point of view, the classification can be envisioned in single- layered swarms with every drone being its own leader and multi- layered swarms with dedicated leader drones at every layer, which report to their leader drones at a higher layer; a ground-based server station is the highest layer in this hierarchy. In each swarm, every drone can have dedicated data collection and processing tasks with sufficient computing capability to execute these tasks in real-time. Its central processing takes place on the more performant server/base station or even in the cloud. The paper is aimed to (1) study the characteristics of the drones and the swarm of drones, (2) discuss the existing technologies of linear and model-based nonlinear controllers, and (3) assess the public awareness levels regarding drones using an experimental query-based survey. To realize these contributions to the field of knowledge, this paper is structured as follows. Section 2 follows this introduction in which drone application fields are discussed. In Section 3, the classification of UAVs is presented. Section 4 lays out the description of the dynamics and flying mechanisms of drones. Section 5 studies key characteristics of autonomous drone swarms. An analysis of public awareness of drones is presented in Section 6. Lastly, conclusions are drawn in Section 7. 2. Application Areas The advances in the capabilities of sensors deployed on UAVs enable the use of drones for different new purposes, facilitating the creation of a new breed of applications and services in the sector of unmanned operations. The prominent application areas of drones are briefly dis- cussed in this section. 2.1. Security, Survey, Monitoring, and Surveillance UAVs have traditionally been employed in military surveillance missions. Versatile and low-cost drones have been utilized in aerial surveys, for monitoring and surveillance, in numerous fields such as geophysics and agriculture [1,2]. For example, surveillance of a facility or environment might require updates of every movement detected after office hours. A large facility or environment would require a lot of manpower for thorough manual surveillance. Contrary to this, a swarm of drones can cover/monitor the region much more efficiently with a https://doi.org/10.1016/j.jii.2019.100106 Received 1 March 2018; Received in revised form 6 August 2019; Accepted 4 October 2019 ⁎ Corresponding author. E-mail addresses: anam.tahir@utu.fi (A. Tahir), jboling@abo.fi (J. Böling), mohammadhashem.haghbayan@utu.fi (M.-H. Haghbayan), hannu.toivonen@abo.fi (H.T. Toivonen), juha.plosila@utu.fi (J. Plosila). Journal of Industrial Information Integration 16 (2019) 100106 Available online 05 October 2019 2452-414X/ © 2019 The Authors. Published by Elsevier Inc. This is an open access article under the CC BY license (http://creativecommons.org/licenses/BY/4.0/). T