Tracking control of a nonholonomic wheeled mobile robot

This paper proposed a tracking control law for the kinematic model of the nonholonomic wheeled mobile robot (WMR). A Lyapunov candidate function is used to prove the stability of the controller. Simulation results verify the effectiveness of the proposed control law, where, a better path tracking of the mobile robot is achieved

Switching between formations for multiple mobile robots via synchronous controller

This paper proposes a new synchronous control law to perform multiple mobile robots trajectory tracking while maintaining time-varying formations. Each robot is controlled to track its desired trajectory while synchronizing its motion with the two nearby robots to maintain the desired time-varying formation. The dynamic model of the wheeled mobile robot (WMR) is derived, so as, it can be divided into a translational and rotational model, in order to control each model separately. Then, a synchronous controller for each robot's translation is proposed to guarantee the asymptotic stability of both position and synchronization errors. Also, an orientation controller is proposed to ensure that the robot is always oriented towards its desired position. The simulation results verify the effectiveness of the proposed synchronous controller in the formation control tasks

Time-varying formation control for nonholonomic wheeled mobile robots via synchronization

In this paper, a new synchronous control law is proposed for multiple nonholonomic wheeled mobile robots (WMR) to perform a time-varying formation task. Each robot is controlled to track its desired trajectory, while synchronized its motion with the two adjoining robots. A novel dynamic model of the WMR is derived based on Lagrange method. The Lagrange multiplier of the WMR is determined based on the input torques and the robot's velocities. The dynamic model has been divided into translational and rotational model. A synchronous translational controller is proposed to guarantee the asymptotic stability of both position and synchronization errors. A rotational controller is designed such that the robot always facing its desired position. A simulation results verified the effectiveness of the proposed synchronous controller in the formation tasks

Synchronizing multi-robots in switching between different formations tasks while tracking a line

This paper extends the synchronization approach for formation control of multiple mobile robots in switching between different time-varying formations tasks while the entire system moving in a line. Each robot in the group is controlled to track its desired trajectory while synchronizing it is motion with the two adjacent robots to maintain a time-varying desired formation. The proposed controller guarantees the asymptotic stability of both position errors and synchronization errors. Simulation results show the effectiveness of the proposed synchronous controller in maintaining formation tasks

Changing formations shapes for multiple robots via synchronization

This paper shows a synchronous controller for multiple mobile robots in switching between time-varying formation. Each robot is forced to track the desired trajectory while synchronizing its movement with the two nearby robots to perform and maintain a desired time-varying formation. The dynamic model of the mobile robot is derived based on the Lagrange Method, and then, it is divided into a translational and rotational dynamic model. The proposed synchronous controller guarantees the asymptotic stability of both position errors and synchronization errors. Simulation are carried out on a group of homogenous multiple mobile robots in switching between different formation shapes in a time-varying manner. The simulation results verify the usefulness of the proposed synchronous controller in the time-varying formation tasks

Trajectory tracking for the quadcopter UAV utilizing fuzzy PID control approach

Currently, the quadcopter Unmanned Aerial Vehicles (UAVs) are playing a significant role in combating the COVID-19 pandemic crisis, which induced the researchers to design robust control techniques. In this paper, a fuzzy PID controller is designed to stabilize and/or track the desired trajectory of the quadcopter UAV. The mathematical model of the quadcopter UAV has been briefly presented, where it has been divided into two portions, the position dynamic and the attitude dynamic subsystems. Subsequently, a robust fuzzy PID controller has been designed for both the inner loop and outer loop to control and stabilize the position and the attitude of the quadcopter, which adaptively manipulate the system's input based on the tracking error. The proposed controller is benchmarked with the conventional PID controller to show the robustness of the fuzzy PID controller. Fuzzy PID controller has been verified through simulation work utilizing Matlab/Simulink, where better performance is achieved compared with the conventional PID controller. It is found that the errors in the quadcopter's attitude and position have been significantly reduced through using fuzzy PID controller by 70% and 87%, respectively