Leader-Follower output reference state feedback synchronization control of Euler-Lagrange systems

Abstract

A coordinated synchronization control scheme to synchronize two or more Euler-Lagrange systems in a leaderfollower configuration is presented where the only information requirements of the leader are that of position and orientation only, i.e. the mathematical model with its parameters and the velocity and acceleration of the leader are considered unknown and unmeasured. An model-based nonlinear observer is designed to indirectly estimate the velocity and acceleration of the leader through the synchronization errors, and the observercontroller scheme is shown to give global uniformly ultimately bounded closed-loop errors.

Dynamic and kinematic observers for output coordination control of Euler-Lagrange systems: A comparison and applications

“…More details of the schemes can be found in Kyrkjebø et al (2006a) and Kyrkjebø and Pettersen (2007). The two observer designs are utilized in the output leader-follower coordination control problem where a fully actuated follower, for which all states are measured and all mathematical parameters are known, synchronizes its motion to the motion of a leader.…”

“…The dynamic model-based observer approach (Kyrkjebø and Pettersen (2007)) is based on designing an error observer for the evolution of the coordination error, and then reconstructing the leader states based on these coordination errors and the states of the follower. Based on the position of the follower x and the position of the leader x m , a position coordination error e forms the basis for the coordination controller and for the dynamic model-based error observer estimatingė andë.…”

“…The dynamic observer approach follows the design in Kyrkjebø and Pettersen (2007) where a model-based observer estimates the unknown states of a leader based on only position/attitude measurements of the leader. The dynamic observer design is based on utilizing information about the model and control signals of the follower to filter the closed-loop errors of the coordination control scheme to generate estimates of the derivatives of the closed-loop errors.…”

“…A shorter version of the results has been presented in Kyrkjebø and Pettersen (2009). The comparison between the kinematic (virtual system) observer approach (based on Kyrkjebø et al (2006a)) and the dynamic (model-based) observer approach (based on Kyrkjebø and Pettersen (2007)) is qualitative -it addresses the difference in estimation principles and the inherent response to disturbances rather than quantifying performance results. The two observer approaches react differently to different types of disturbances, and this paper focuses on providing knowledge and guidelines for choosing estimation principles for a wide range of coordination applications through a comparison of the two presented observer schemes.…”

Robust synchronization control of multiple vessels with communication delays

“…And a cooperative synchronization control law of multiple autonomous underwater vehicles is presented by C. R. Xin [9], in both state feedback and output feedback are designed to achieve synchronization. And without the mathematical model of the leader, E. Kyrkjebø designs a nonlinear observer to estimate the unknown states of the follower and a feedback controller was designed [9,10]. The synchronization of multiple systems with time delays is discussed in [11,12].…”