چكيده به لاتين
In recent years, multi-agent robotic systems have found very diverse operational applications in military and civilian fields. Among these systems, we can mention the multi-agent systems consisting of unmanned aerial vehicles, which include various types of aircraft, including quadrotors. These systems are widely used today due to the many advantages they have from different perspectives. If we consider the various applications of multi-agent systems consisting of quadrotors in general, in most applications, it is necessary that the quadrotors in the system form a specific configuration and track a desired trajectory, which may be a predesigned trajectory or the trajectory of a specified target. This issue is known as formation control in multi-agent systems, which has been one of the hot research topics in the field of control in recent years, and many researchers around the world have provided solutions to solve this research challenge. In the present research, firstly, the various aspects of formation control, the existing challenges, the proposed algorithms in previous researches, and the weaknesses in these methods have been examined, and then, according to the existing challenges, a new control structure for controlling the formation in a system consisting of quadrotors is presented. The communication topology of the leader-follower type is considered, in which it is assumed that three follower robots follow the movement of the leader robot. It was assumed that the movement environment of quadrotors is without static and dynamic obstacles and the system states and relative speed between the followers are not available and there is no sensor to measure them. Also, the saturation of actuators, which is one of the most important issues in the design of control systems, has been considered in the current research. Based on the assumptions made, a control method consisting of the dynamic surface control (DSC) method and the non-linear extended state observer (N-ESO) is presented for the formation control. The dynamic surface control method has been chosen in order to solve the problems of the Backstepping control method that has been used more in previous researches, to avoid the increase in the volume of calculations that we face in the Backstepping method and to avoid doing what is known as “Complexity Explosion”. Considering that there are dynamic uncertainties and external disturbances in the system, and we are also facing the problem of the unavailability of system states, in order to avoid the design of estimator and observer for each of the above cases, which causes the complexity of the control structure, in the current research, a non-linear extended state observer has been used in which the system disturbances, which are a combination of external disturbances and the effect of dynamic uncertainties that can be modeled as external disturbances, are defined as one of the system states, and therefore the estimation of the system states and system disturbances through A single observer has been made, which has significantly reduced the amount of required calculations and made the proposed control structure simpler. The proposed control system has been simulated in MATLAB software, and the obtained results show the efficiency of the method presented in the present research in controlling the formations of multi-agent systems. Also, the results of the present study have been compared with the results of previous valid studies in this field, and the results of the comparison show a very good performance and almost equal to the complex control methods with a very high computational volume available in previous studies
