Formation control of nonholonomic mobile robots (original) (raw)
Stable formation control for a team of wheeled mobile robots
2007
This paper presents a novel control algorithm and visual measurement for the autonomous navigation of a non-holonomic robot team while preserving a specified formation. The control errors are defined relative to the leader robot of the team in terms of the actual position of each robot and its desired position in the formation. The stability analysis as well as a robustness analysis for the proposed control system is presented. This paper also includes some experimental results to show the good performance of the proposed control system.
Formation Control and Trajectory Tracking of Nonholonomic Mobile Robots
IEEE Transactions on Control Systems Technology, 2018
In this brief, we design Lyapunov-based control laws to achieve two multi-objective tasks for a network of open-loop unstable, nonholonomic mobile inverted pendulum (MIP) robots, using a connected undirected graph for inter-agent communication. Using the first protocol, translationally invariant formations are achieved along with the synchronization of attitudes and heading velocities to desired values. Using the second protocol, the robots move into a formation and asymptotically track a trajectory. The control laws are based on the kinematic model of the mobile robot, and control torques for the MIPs are extracted using a two-loop control architecture. Both the protocols guarantee boundedness of the linear heading velocity, which is necessary for the stability of the two-loop control architecture. The proposed control laws are experimentally validated on indigenously built MIP robots.
Hybrid Consensus-Based Formation Control of Nonholonomic Mobile Robots
In this chapter, a hybrid consensus-based formation controller is designed for mobile robots. First, omnidirectional (holonomic) robots are considered in the controller development to create a hybrid automaton, which drives the robots to their goal positions while maintaining a specified formation. The controller consists of two discrete modes, each with continuous dynamics: a regulation mode and a formation keeping mode. The controller in the regulation mode is designed to drive the robot to a goal position, while the formation keeping controller ensures that the robots achieve a specified geometric formation prior to reaching their goal-position. The proposed approach is subsequently extended to include formation control of nonholonomic mobile robots. Lyapunov methods are used to demonstrate that the formation errors converge to a small bounded region around the origin; moreover, the size of the bound can be adjusted by using the switching conditions. Convergence to goal position while in formation is also demonstrated in the same Lyapunov analysis, and simulation results verify the theoretical conjectures.
Consensus for formation control of nonholonomic mobile robots
2009 IEEE International Conference on Robotics and Automation, 2009
In this article we present novel formation control laws based on artificial potential fields and consensus algorithms for a group of unicycles enabling arbitrary formation patterns for these nonholonomic vehicles. Given connected and balanced graphs we are able to prove stability of the rendezvous controller by applying the LaSalle-Krasovskii invariance principle. Further, we introduce obstacle avoidance, enabling a reactive behavior of the robotic group in unknown environments. The effectiveness of the proposed controllers is shown using computer simulations and finally, a classification w.r.t. existing solutions is done.
Hybrid Consensus-based Control of Nonholonomic Mobile Robot Formation
Journal of Intelligent and Robotic Systems, 2017
This paper addresses the hybrid consensusbased formation keeping problem for nonholonomic mobile robots in the presence of a novel time-varying, composite, nonlinear velocity-tracking error system. First, continuous-time regulation and consensus-based formation controllers are developed for a group of wheeled mobile robots. These controllers are then used to create a hybrid automaton, which drives the robots to their goal positions while maintaining a specified formation. In order to avoid the hard switches between regulation and formation keeping controllers, a novel blended velocity tracking error approach is proposed in this work to create nonlinear, Haci Mehmet Güzey ( ) Department of Electrical & Computer Engineering,
Formation control and trajectory tracking of mobile robotic systems – a Linear Algebra approach
Robotica, 2010
A novel approach for trajectory tracking of a mobile-robots formation by using linear algebra theory and numerical methods is presented in this paper. The formation controller design is based on the formation states concept and the dynamic model of a unicycle-like nonholonomic mobile robot. The proposed control law designed is decentralized and scalable. Simulations and experimental results confirm the feasibility and the effectiveness of the proposed controller and the advantages of using the dynamic model of the mobile robot. By using this new strategy, the formation of mobile robots is able to change its configuration (shape and size) and follow different trajectories in a precise way, minimizing the tracking and formation errors.
Hybrid Formation Control for Non-Holonomic Wheeled Mobile Robots
2008
This paper presents a hybrid formation controller approach for nonholonomic mobile robots. This approach is based on the stable switching between a leader-following formation controller and an orientation controller. The switching attempts to maintain low values of formation errors during specific leader movements that otherwise will produce a significant increment on such errors. Experimental results on commercial unicycle-like mobile robots are provided to show the feasibility and performance of the proposed control strategy.
Formation control of mobile robots
World Academy of Science, Engineering and Technology, International Journal of Mechanical, Aerospace, Industrial, Mechatronic and Manufacturing Engineering, 2011
In this paper, we study the formation control problem for car-like mobile robots. A team of nonholonomic mobile robots navigate in a terrain with obstacles, while maintaining a desired formation, using a leader-following strategy. A set of artificial potential field functions is proposed using the direct Lyapunov method for the avoidance of obstacles and attraction to their designated targets. The effectiveness of the proposed control laws to verify the feasibility of the model is demonstrated through computer simulations.
A Stable Control Algorithm for Multi Robot Formation
IOP Conference Series: Materials Science and Engineering
This paper presents the developed trajectory tracking controller for a formation of nonholonomic robots, which combines features from the leader-follower and virtual-structure approaches. The implemented decentralized control strategy allows the robots to be relatively independent and to switch easily between the executed individual tasks and the collective tasks. Convergence is thoroughly analyzed and guarantied using the Lyapunov approach.
ADAPTIVE FORMATION CONTROL OF NONHOLONOMIC MOBILE ROBOTS FOR AUTONOMOUS FOLLOWING IN FRONT OF THE LEADER, 2021
This paper addresses the control of an autonomous leader-follower formation of nonholonomic mobile robots in a specific case, when the following robot is moving ahead of the leading robot. Using a look-ahead approach, first, a kinematic model of the leader-follower formation in error coordinates is developed. A nonlinear feedback control is design using only information for the relative position and orientation between the robots. An adaptive control is proposed to deal with the unknown leader linear and angular velocities, which are not available for the feedback control design. Using Lyapunov stability theory, asymptotic stability property of the closed-loop system is established. The performance of the proposed adaptive leader-following formation controller is illustrated through numerical simulations.