Sampled‐data leader‐following consensus of second‐order nonlinear multiagent systems without velocity measurements

Abstract

Summary In this paper, the practical leader‐following consensus via the sampled‐data protocol is investigated for second‐order nonlinear multiagent systems with external disturbances, where the velocity information of all agents are assumed to be unmeasurable. The consensus problem of the multiagent system is first transformed to a stabilization problem of the constructed error system. Because of the unknown of the agents' velocities, an observer is then proposed for the constructed error system to estimate the velocity errors. By the backstepping approach, a new protocol is designed with only position measurements and sampled‐data information. Furthermore, the upper bound of the sampling period is given. It is proved that the practical leader‐following consensus can be achieved by the proposed sampled‐data protocol with a proper sampling period. The result is then extended to the multiagent systems with multiple leaders. Finally, two numerical examples are provided to illustrate the effectiveness of the designed protocols.

Delay-Induced Containment Control of Second-Order Multi-Agent Systems With Intermittent Sampled Position Data

“…Remark 1: Note that observer-based (filter-based) control and sampled data control strategies [29]- [35] overcome the shortage that the sensors have difficulty in obtaining accurate velocity information in reality, while they need the controller to work under continuous communication. Although the intermittent sampled data control strategy [36] solves the second-order consensus problem under intermittent communication, the controllers need to use both relative position and relative velocity measurements.…”

“…Under directed communication topology, a novel distributed consensus protocol was designed for second-order linear multi-agent systems based on only causal sampled position data in [34]. In [35], the sampled-data leader-following consensus of second-order nonlinear multi-agent systems without velocity measurements was investigated. Under intermittent communication, the second-order consensus for multi-agent systems was solved via sampled data control [36].…”

Sampled‐data output feedback leader‐following consensus for a class of nonlinear multi‐agent systems with input unmodeled dynamics

“…Overall, although the continuous‐time consensus of nonlinear multi‐agent system has drawn enough attention, few results focus on the sampled‐data observer‐based leader‐following consensus of nonlinear multi‐agent systems. In the previous literature, 37 a sampled‐data leader‐following consensus was obtained for a class of second‐order nonlinear multi‐agent systems with unavailable velocities and positions. In such literature, we noticed that the control coefficient of each agent was restricted to be “1,” and the input unmodeled dynamics which may disrupt the consensus protocols were also ignored, which naturally causes some open problems behind the above‐mentioned literature:…”

Velocity‐free coordinated attitude synchronisation and tracking control of multiple spacecraft

“…Therefore, it is worth developing distributed control algorithms without depending on angular velocity measurements. Although numerous velocity‐free distributed control schemes have been proposed for second‐order linear multi‐agent systems [24, 25], they cannot be directly implanted to the attitude synchronization and tracking problems because of strong non‐linearity. By assuming that the leader was accessible to all the followers, [26] studied the coordinated attitude control problem in the absence of angular velocity measurements, and a velocity‐free attitude tracking control scheme was designed by introducing an auxiliary dynamic system.…”