Prescribed-time distributed optimization problem with constraints.

In recent years, distributed optimization problem have a wide range of applications in various fields. This paper considers the prescribed-time distributed optimization problem with/without constraints. Firstly, we assume the state of each agent is constrained, and the prescribed-time distributed optimization algorithm with constraints is designed on the basis of gradient projection algorithm and consensus algorithm. Secondly, the constrained distributed optimization problem is transformed into the unconstrained distributed optimization problem, and according to the gradient descent algorithm and consensus algorithm, we also propose the prescribed-time distributed optimization algorithm without constraints. By designing the appropriate objective functions, we prove the multi-agent system can converge to the optimal solution within any prescribed-time, and the convergence time is fully independent of the initial conditions and system parameters. Finally, three simulation examples are provided to verify the validity of the designed algorithms.

Induced attack with prescribed consensus trajectory against multiagent systems.

This paper proposes a new induced attack strategy against multiagent systems from the perspective of the attacker. It is noted that the induced attack can drive multiagent systems as a whole to follow a specific trajectory prescribed by the attacker, which cannot be achieved by denial-of-service attacks or deception attacks. Firstly, the induced attack signal is produced by establishing an attack generation exosystem, whose dynamics can be regulated to generate the prescribed consensus trajectory. Then, by the local state information and the induced attack signal among partial agents, a new induced attack protocol is proposed, which consists of the nominal consensus term and the induced attack term. By constructing the projection of the induced attack signal onto the consensus subspace, an explicit expression of the prescribed consensus trajectory is determined, which describes the movement trajectory of the entire multiagent system under the induced attack. Meanwhile, the induced attack design criterion is proposed to determine the dynamics matrix of the attack generation exosystem via the robust H∞ scheme. Finally, the simulation example is performed to illustrate the effectiveness of theoretical results.

Distributed formation for interconnected networks with minimum energy restriction and interaction silence.

The minimum-energy formation strategy for interconnected networks with distributed formation protocols is persented, where the impacts of the total energy restriction and the interaction silence are analyzed, respectively. The critical feature of this article is that the distributed formation and the minimum-energy restriction are realized simultaneously, and the total energy restriction is minimum in the sense of the linear matrix inequality. However, the guaranteed-cost formation strategy and the limited-budget formation strategy cannot guarantee that the energy restriction is minimum. Firstly, sufficient conditions for minimum-energy-restriction formation without the interaction silence are proposed, which can be solved by a specific optimization approach in terms of the linear matrix inequality, and the formation whole motion trajectory is determined, which is closely related to the average of the initial states of all agents and formation control vectors. Then, minimum-energy-restriction formation criteria for interconnected systems with the interaction silence are proposed by introducing two inhibition parameters and the interaction silence rate. Finally, two simulation examples are performed to illustrate the effectiveness of theoretical analyses.

Game-Based Consensus of Hybrid Multiagent Systems.

This article considers consensus of first-order/second-order hybrid multiagent systems (MASs) based on game modeling. In the first-order hybrid MAS (HMAS), a subset of agents select the Nash equilibrium of a multiplayer game as their states at each game time and the others update their states with first-order continuous-time (C-T) dynamics. By graph theory and matrix theory, we establish sufficient and necessary conditions for consensus of the first-order HMAS with two proposed protocols. The second-order HMAS is composed of agents whose states are determined by the Nash equilibrium of a multiplayer game and agents whose states are governed by second-order C-T dynamics. Similarly, sufficient and necessary conditions are given for consensus of the second-order HMAS with two proposed protocols. Several numerical simulations are provided to verify the effectiveness of our theoretical results.

Energy-constraint output formation for swarm systems with dynamic output feedback control protocols.

This paper studies the energy-constraint output formation control for swarm systems with leaderless and leader-following topology structures. Most existing results on output formation with the dynamic output feedback protocols focus on the swarm systems without the energy constraint, but it is well known that the energy constraint is critically important for practical applications. In order to analyze the impacts of the energy constraint, a new energy-constraint output formation protocol is proposed. First, by the observable decomposition approach, a dynamic output formation protocol is presented, which contains an energy-constraint term to restrict the whole consumption. Then, sufficient conditions for leaderless energy-constraint output formation are presented via establishing the relationship of the energy constraint and the matrix variables, where it is found that the designed gain matrices of the output formation protocol can ensure that the actual energy consumption is lower than the total energy supply. Especially, a partition checking algorithm is proposed to check those conditions, which can ensure the scalability and solvability of a swarm system. Moreover, the output formation center function is derived to depict the whole macroscopic movement of a swarm system. A nonsingular transformation approach is presented to unify leaderless energy-constraint output formation and energy-constraint output formation tracking into the same framework, which are usually discussed in different theoretical frameworks. Finally, two simulation examples are illustrated to show that the theoretical results about leaderless energy-constraint output formation and energy-constraint output formation tracking are correct.

Budget-constraint admissible output consensus tracking for intermittent-interaction singular multiagent networks.

Budget-constraint admissible output consensus tracking design and analysis for the intermittent-interaction singular multiagent networks with given cost budgets are addressed in this paper. Two critical characteristics of many practical multiagent networks are focused. The first one is that the dynamics of each agent contains dynamical modes, as well as impulsive modes and static modes, and interactions among agents are intermittent. The second one is that the network is constrained by the cost budget, and the weighted design between tracking performances and energy consumptions should be guaranteed under budget constraints. Firstly, in virtue of the decomposition of observability, a new singular consensus tracking protocol with the dynamic output feedback is proposed by intermittent protocol states. Meanwhile, a cost index is constructed by considering both the tracking performance and the energy consumption. Then, criteria of budget-constraint admissible output consensus tracking analysis and design are given. By designing the gain matrices of consensus tracking protocols, not only multiagent networks with dynamical modes and static modes reach output consensus tracking while eliminating impulsive modes, but also the upper bound of the cost index can be kept within the cost budget; that is, the weighted design with the budget constraint is achieved. Finally, theoretical results are demonstrated by numerical simulations.

Limited-Budget Output Consensus for Descriptor Multiagent Systems With Energy Constraints.

This article deals with limited-budget output consensus for descriptor multiagent systems with two types of switching communication topologies, that is, switching connected ones and jointly connected ones. First, a singular dynamic output feedback control protocol with switching communication topologies is proposed on the basis of the observable decomposition, where an energy constraint is involved and protocol states of neighboring agents are utilized to derive a new two-step design approach of gain matrices. Then, limited-budget output consensus problems are transformed into asymptotic stability ones and a valid candidate of the output consensus function is determined. Furthermore, sufficient conditions for limited-budget output consensus design and analysis for two types of switching communication topologies are proposed, respectively, and an explicit expression of the output consensus function is given, which is identical for two types of switching communication topologies. Finally, two numerical simulations are shown to demonstrate theoretical conclusions.

An Alignment Method for Strapdown Inertial Navigation Systems Assisted by Doppler Radar on a Vehicle-Borne Moving Base.

In this study, we investigated a novel method for high-accuracy autonomous alignment of a strapdown inertial navigation system assisted by Doppler radar on a vehicle-borne moving base, which effectively avoids the measurement errors caused by wheel-slip or vehicle-sliding. Using the gyroscopes in a strapdown inertial navigation system and Doppler radar, we calculated the dead reckoning, analyzed the error sources of the dead reckoning system, and established an error model. Then the errors of the strapdown inertial navigation system and dead reckoning system were treated as the states. Besides velocity information, attitude information was cleverly introduced into the alignment measurement to improve alignment accuracy and reduce alignment time. Therefore, the first measurement was the difference between the output attitude and velocity of the strapdown inertial navigation system and the corresponding signals from the dead reckoning system. In order to further improve the alignment accuracy, more measurement information was introduced by using the vehicle motion constraint, that is, the velocity output projection of strapdown inertial navigation system along the transverse and vertical direction of the vehicle body was also used as the second measurement. Then the corresponding state and measurement equations were established, and the Kalman filter algorithm was used for assisted alignment filtering. The simulation results showed that, with a moving base, the misalignment angle estimation accuracy was better than 0.5' in the east direction, 0.4' in the north direction, and 3.2' in the vertical direction.