Distributed Control for a Robotic Swarm to Pass through a Curve Virtual Tube

Abstract

Robotic swarm systems are now becoming increasingly attractive for many challenging applications. The main task for any robot is to reach the destination while keeping a safe separation from other robots and obstacles. In many scenarios, robots need to move within a narrow corridor, through a window or a doorframe. In order to guide all robots to move in a cluttered environment, a curve virtual tube with no obstacle inside is carefully designed in this paper. There is no obstacle inside the tube, namely the area inside the tube can be seen as a safety zone. Then, a distributed swarm controller is proposed with three elaborate control terms: a line approaching term, a robot avoidance term and a tube keeping term. Formal analysis and proofs are made to show that the curve virtual tube passing problem can be solved in a finite time. For the convenience in practical use, a modified controller with an approximate control performance is put forward. Finally, the effectiveness of the proposed method is validated by numerical simulations and real experiments. To show the advantages of the proposed method, the comparison between our method and the control barrier function method is also presented in terms of calculation speed.

Robust Distributed Control within a Curve Virtual Tube for a Robotic Swarm under Self-Localization Drift and Precise Relative Navigation

“…1, the concept of the curve virtual tube is similar to the lane for autonomous road vehicles [11], the safe flight corridor for quadcopters [2], and the multi-drone skyway framework CORRIDRONE [12]. To guide and control a robotic swarm within a curve virtual tube, a distributed vector field controller is proposed in [9], which is a type of controlbased method. However, there is no uncertainty considered in [9], namely all robots can obtain the information precisely and execute the command exactly.…”

“…To guide and control a robotic swarm within a curve virtual tube, a distributed vector field controller is proposed in [9], which is a type of controlbased method. However, there is no uncertainty considered in [9], namely all robots can obtain the information precisely and execute the command exactly. It is obvious that this assumption is too ideal for real practice.…”

“…Any robot has no need to identify other robots carefully, and the system structure is greatly simplified. To modify the original controller in [9], three kinds of flocking behaviors of the Boids model [25], namely cohesion behavior, collision avoidance behavior, and velocity alignment behavior, are introduced. The controller in [9] already includes a collision avoidance term for guaranteeing safety among robots.…”

“…To modify the original controller in [9], three kinds of flocking behaviors of the Boids model [25], namely cohesion behavior, collision avoidance behavior, and velocity alignment behavior, are introduced. The controller in [9] already includes a collision avoidance term for guaranteeing safety among robots. This paper shows that the cohesion behavior and the velocity alignment behavior can reduce the negative impact of the position measurement drift and the velocity measurement error, respectively.…”

“…In our previous work [9], a curve virtual tube is proposed for guiding the robotic swarm in a corridor-like environment. There is no obstacle inside the curve virtual tube, and robots Yan Gao, Chenggang Bai and Quan Quan are with the School of Automation Science and Electrical Engineering, Beihang University, Beijing 100191, P. R. China (email: buaa gaoyan@buaa.edu.cn; bcg@buaa.edu.cn; qq buaa@buaa.edu.cn).…”