Trajectory planning is a core technology for autonomous vehicle directlyreflecting the driving safety and efficiency. In this paper, a spatial‐speed decoupled planning method is studied for real‐time ...trajectory generation in the on‐road environment. The proposed approach mainly includes two parts: optimization‐based lateral planning and selection‐based longitudinal speed planning. The optimization‐based lateral planning is employed to generate an optimal collision‐free and smooth path by solving a quadratic programming problem. Specifically, the lateral planning first constructs a safe corridor by integrating obstacles and initial risky corridor together in the Frénet frame. The safe corridor is useful for quadratic programming problem formulation. The selecting‐based longitudinal speed planning is proposed to generate a suitable and continuous velocity trajectory. The novel speed selector considering four cases is designed to select a more suitable reference velocity in different lane situations. The continuous velocity trajectory is obtained by solving piecewise continuous quartic polynomial. As a result, the combination of the spatial path and the velocity trajectory is the final planning result. The proposed algorithm is tested extensively in a simulation environment. Experimental results demonstrate that the proposed algorithm has good real‐time property and practical validity.
In this study, a robust cooperative control methodology is proposed for a class of micro/nano scale systems in the field of biomedical engineering. Due to the complexity of actual environment, the ...dynamic behavior of the micro/nano scale systems changes over time. The time-varying uncertainties are considered to be restricted to a certain range. Then, a robust cooperative control strategy is designed such that the micro-agents with structured uncertainties can securely cooperative with each other to accomplish the tasks. Furthermore, sufficient conditions ensuring the cooperativity of micro/nano scale systems are derived by constructing a novel Lyapunov functional. It is proved that the cooperative control problem for micro/nano scale systems can be solved if the control parameters are appropriately selected. A simulation example is presented to demonstrate the validity of the obtained algorithm.
In this paper, the synchronization of Chaotic Lur’e systems subject to aperiodic sampling is investigated. It is shown that sampling interval is bounded and nonuniform. A modified free-matrix-based ...(MFMB) time-dependent Lyapunov functional is developed to capture the information on sampling pattern, which is sufficiently used to analyze stability of Chaotic Lur’e systems. For a special case that the sampled-data controller suffers constant input delay, a discontinuous Lyapunov functional is presented based on the vector extension of Wirtinger’s inequality. The obtained stability condition leads to a less computational complexity than some of existing works. A longer value on the calculation of sampling interval is achieved. Two illustrative examples demonstrate the effectiveness of designed methods and less conservatism of the obtained results.
Efficient intersection planning is one of the most challenging tasks for an autonomous vehicle at present. Politeness to other traffic participants and reaction to surrounding information are the key ...aspects that determine the performance of planning algorithm for an autonomous vehicle. In order to capture these aspects, we propose a planning framework, based on the partially observable Markov decision process (POMDP), to ensure social compliance and optimize the motion response of autonomous vehicles. The framework designs a novel POMDP model to ensure effective prediction of behavioral intentions and decision-making at intersections with no traffic signs and low traffic volume. Then, a deterministic planner is employed as the baseline to realize planning. Specifically, we consider both the driving position and the facing angle of the vehicle in real-world situations. At the same time, we utilize scattering methods for probability updating and intent determination to improve the algorithm's adaptability to real-world scenarios. The proposed framework is evaluated in different scenarios to demonstrate its capabilities in terms of the interactive planning for an autonomous vehicle.
This paper is concerned with the distributed consensus control for a group of autonomous marine vehicles with nonlinearity and external disturbances via sampled-data communications. First, the ...kinematical equation of autonomous marine vehicle is established. Second, stability criteria is derived to ensure the stability of autonomous marine vehicles by combining Lyapunov function method and free-weighting matrix approach. Third, a distributed sampled-data control strategy is proposed to achieve the consensus of autonomous marine vehicles by designing suitable control parameters. Numerical simulations are provided to verify the effectiveness of the proposed consensus control approach.
This article investigates the leader-following consensus problem of discrete-time nonlinear multiagent systems (MASs) over fading channels. With the consideration of the transmission among followers ...maybe affected by the fading networks, the nonidentical fading channels model is constructed. To reduce the transmission network burden, the dynamical event-triggered mechanism (DETM) is developed. Different from most of existing event-triggered strategies, the threshold parameter in the developed dynamical event-triggering condition is dynamically adjusted according to a dynamic rule. Based on the DETM, a distributed consensus control protocol is designed under fading channels. Then, sufficient criteria are provided to ensure that MASs can achieve the leaser-following consensus, and satisfy the <inline-formula> <tex-math notation="LaTeX">H_{\infty } </tex-math></inline-formula> performance index in the presence of fading channels. The desired controller parameters can be derived in terms of solutions of matrix inequalities that are lightly solvable. In the end, simulation results show that the designed dynamical event transmission policy is capable of diminishing communication burden more promptly and effectively than some existing ones.
This article investigates two kinds of leader-following formation control problems of second-order autonomous unmanned systems under directed topology, that are, the cases with constant velocity and ...time-varying velocity for the leader. First, the kinematical equation of autonomous unmanned systems is established according to some real scenarios. Second, by assuming the velocity of the leader is constant, a sufficient condition ensuring the formation control of autonomous unmanned systems is derived and some control parameters are suitably designed. Third, it is assumed that the velocity of leader is time-varying, and the formation controller with two parts is designed. The first part is intended to form the desired formation of all followers and the second part aims to reach the consensus of velocity. Some simulation examples are finally presented to verify the effectiveness of the obtained theoretical results.
•A discontinuous ISMC consensus protocol for the tracking control of NCSs with disturbances is developed.•The proposed protocol has complete robustness due to rejecting the disturbances and ...eliminating the reaching phase.•There not exists the singularity problem which obsesses terminal sliding mode control (TSMC) in the developed scheme.•The adaptive continuous ISMC protocol is investigated, the chattering of the system is free.
The finite-time consensus tracking of multi-robotic systems with disturbances is investigated via utilizing integral sliding mode control (ISMC) in this article. The main focus of this article is on designing consensus tracking protocols. Firstly, combined with Lyapunov stabilization theory, a continuous super-twisting (ST) consensus protocol is proposed to obtain the sufficient condition, which can guarantee the accuracy consensus of multi-robotic systems in the presence of disturbances in finite-time. Secondly, the adaptive mechanism and ISMC are integrated for multi-robotic systems without the prior knowledge of disturbances. It is easy to find that it can prevent the limited growth of the switching gain. In addition, the disturbance of multi-robotic systems can be estimated by designing a fascinating disturbance observer. The consensus tracking of multi-robotic systems can be assured in finite-time. Finally, the effectiveness of the presented adaptive ISMC strategy is demonstrated by two numerical examples.
This paper investigates the finite-time synchronization problem of complex networks subject to input delay. The time-varying sampling is required to be aperiodic, which implies that the difference of ...any two continuous sampling instants does not exceed a given upper bound. Together with free-weighting matrix approach, a fresh Lyapunov functional is employed to establish a sufficient condition, solving the finite-time synchronization problem. Then, the synchronization of complex networks with input time-varying delay within a given time interval is considered. In order to solve such a problem, sufficient conditions are obtained based on non-fragile control protocol, the Lyapunov-Krasovskii stability theory (LKST) and integral inequality. The finite-time stability of complex networks in the presence of delay input delay can be achieved. At last, the smaller conservatism and the effectiveness of the obtain theoretical result is exhibited through some numerical simulations.
A novel control strategy for synchronization control for network systems with communication constraints is presented in this paper. The dynamics of nodes in the network are nonidentical. The ...communication topology of network is weakly connected with communication constraints. The designed distributed controller for each node has two parts: reference generator (RG) and regulator. All RGs adopt the communication channels to exchange local information and track the target trajectory. Meanwhile, regulator can ensure that nonidentical node achieves synchronization with its RG. In order to reduce the communication frequency between node and its regulator, a sampled-date control strategy is utilized. The upper bound of the aperiodic sampling instants is calculated through the small-gain theorem, where the closed-loop system is equivalently formulated as the feedback interconnection of a linear time-invariant system and an integral sampled-data operator. Finally, some simulation results are given to demonstrate the effectiveness of the controller design strategy.
