Multi-UAV Flight using Virtual Structure Combined with Behavioral Approach

Abstract

Implementations of multi-UAV systems can be divided mainly into two different approaches, centralised system that synchronises positions of each vehicle by a ground station and an autonomous system based on decentralised control, which offers more flexibility and independence. Decentralisation of multi-UAV control entails the need for information sharing between all vehicles, what in some cases could be problematic due to a significant amount of data to be sent over the wireless network. To improve the reliability and the throughput of information sharing inside the formation of UAVs, this paper proposes an approach that combines virtual structure with a leader and two flocking behaviours. Each UAV has assigned different virtual migration point referenced to the leader's position which is simultaneously the origin of a formation reference frame. All migration points create together a virtual rigid structure. Each vehicle uses local behaviours of cohesion and repulsion respectively, to track its own assigned point in the structure and to avoid a collision with the previous UAV in the structure. To calculate parameters of local behaviours, each UAV should know position and attitude of the leader to define the formation reference frame and also the actual position of the previous UAV in the structure. Hence, information sharing can be based on a chain of local peer-to-peer communication between two consecutive vehicles in the structure. In such solution, the information about the leader could be sequentially transmitted from one UAV to another. Numerical simulations were prepared and carried out to verify the effectiveness of the presented approach. Trajectories recorded during those simulations show collective, coherence and collision-free flights of the formation created with five UAVs.

Practical Aspects of Design and Testing Unmanned Aerial Vehicles

“…It involves melting the material and laying it in thin paths, one next to another. The layers of plastic bond together, cooling down (Kownacki, 2016). For printing, the legs and two elements of the electronics housing the rubber material (TPU) and polycarbonate were used.…”

Asymmetrical Artificial Potential Field as Framework of Nonlinear PID Loop to Control Position Tracking by Nonholonomic UAVs

“…Position tracking is one of the most useful features of present unmanned aerial vehicles. It can be adopted in a variety of applications, starting from formation flights [ 1 , 2 , 3 ],through operations such as moving platforms [ 4 , 5 ], ending with visual feature tracking [ 6 , 7 ], such person tracking [ 8 ], which is common in commercial drone solutions (e.g., DJI). In each of them, the precision of keeping the desired position or distance from a moving reference point plays a crucial role.…”

“…Limited maneuverability resulting in minimum turn radius requires applying different approaches. Therefore, the leader–follower formation control scheme is more popular in the case of fixed-wing UAVs (unmanned aerial vehicles) than other methods [ 3 , 11 , 12 , 13 , 14 ]. The leader–follower control scheme assumes that the follower UAV tracks the leader UAV’s position at a predefined safe distance, which is, in fact, the predefined set-point value of the tracking error.…”

Simulation and Analysis of Grid Formation Method for UAV Clusters Based on the 3 × 3 Magic Square and the Chain Rules of Visual Reference

“…At present, there are five commonly used plane formation methods: the leader-follower method [4][5][6][7][8][9][10], the behavior-based method [11][12][13][14][15][16], the virtual structure method [17][18][19][20][21][22][23][24][25][26], the graph theory method [27][28][29][30][31][32][33], and the consistency method [34][35][36][37][38][39][40][41][42][43][44][45]. However, these methods do not consider the stability of UAV formation planes when they are destroyed or decoyed by the enemy on the battlefield.…”