@article{AliMontenegro2016,
  author    = {Ali, Qasim and Montenegro, Sergio},
  title     = {Decentralized control for scalable quadcopter formations},
  series = {International Journal of Aerospace Engineering},
  volume    = {2016},
  journal   = {International Journal of Aerospace Engineering},
  doi       = {10.1155/2016/9108983},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-146704},
  pages     = {9108983},
  year      = {2016},
  abstract  = {An innovative framework has been developed for teamwork of two quadcopter formations, each having its specified formation geometry, assigned task, and matching control scheme. Position control for quadcopters in one of the formations has been implemented through a Linear Quadratic Regulator Proportional Integral (LQR PI) control scheme based on explicit model following scheme. Quadcopters in the other formation are controlled through LQR PI servomechanism control scheme. These two control schemes are compared in terms of their performance and control effort. Both formations are commanded by respective ground stations through virtual leaders. Quadcopters in formations are able to track desired trajectories as well as hovering at desired points for selected time duration. In case of communication loss between ground station and any of the quadcopters, the neighboring quadcopter provides the command data, received from the ground station, to the affected unit. Proposed control schemes have been validated through extensive simulations using MATLAB®/Simulink® that provided favorable results.},
  language  = {en}
}
@article{AliMontenegro2016,
  author    = {Ali, Qasim and Montenegro, Sergio},
  title     = {Explicit Model Following Distributed Control Scheme for Formation Flying of Mini UAVs},
  series = {IEEE Access},
  volume    = {4},
  journal   = {IEEE Access},
  number    = {397-406},
  doi       = {10.1109/ACCESS.2016.2517203},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-146061},
  year      = {2016},
  abstract  = {A centralized heterogeneous formation flight position control scheme has been formulated using an explicit model following design, based on a Linear Quadratic Regulator Proportional Integral (LQR PI) controller. The leader quadcopter is a stable reference model with desired dynamics whose output is perfectly tracked by the two wingmen quadcopters. The leader itself is controlled through the pole placement control method with desired stability characteristics, while the two followers are controlled through a robust and adaptive LQR PI control method. Selected 3-D formation geometry and static stability are maintained under a number of possible perturbations. With this control scheme, formation geometry may also be switched to any arbitrary shape during flight, provided a suitable collision avoidance mechanism is incorporated. In case of communication loss between the leader and any of the followers, the other follower provides the data, received from the leader, to the affected follower. The stability of the closed-loop system has been analyzed using singular values. The proposed approach for the tightly coupled formation flight of mini unmanned aerial vehicles has been validated with the help of extensive simulations using MATLAB/Simulink, which provided promising results.},
  language  = {en}
}
@article{MontenegroAliGageik2014,
  author    = {Montenegro, Sergio and Ali, Qasim and Gageik, Nils},
  title     = {A review on Distributed Control of Cooperating MINI UAVs},
  doi       = {10.5121/ijaia.2014.5401},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-113009},
  year      = {2014},
  abstract  = {Mini Unmanned Aerial Vehicles (MUAVs) are becoming popular research platform and drawing considerable attention, particularly during the last decade due to their multi-dimensional applications in almost every walk of life. MUAVs range from simple toys found at electronic supermarkets for entertainment purpose to highly sophisticated commercial platforms performing novel assignments like offshore wind power station inspection and 3D modelling of buildings. This paper presents an overview of the main aspects in the domain of distributed control of cooperating MUAVs to facilitate the potential users in this fascinating field. Furthermore it gives an overview on state of the art in MUAV technologies e.g. Photonic Mixer Devices (PMD) camera, distributed control methods and on-going work and challenges, which is the motivation for many researchers all over the world to work in this field.},
  language  = {en}
}