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A nonlinear passive robust filtering method is described in this article to solve filtering and state estimation problems of ship dynamic positioning system (DPS) in slowly varying sea state. By augmenting a new state and utilizing acceleration feedback technology, the observer proposed in this paper will improve disturbance attenuation performance. The global stability and passivity of the observer...
This article mainly presents a control method for an underactuated tractor-trailer vehicle, subject to the nonholonomic constraint, uncertain disturbance and various physical limits, which is aimed at receiving a good tracking performance. All in all, linear quadratic regulator (LQR) and model predictive control (MPC) are used to design the posture controller to make the midpoint of two parallel plating...
This thesis studies the tracking control problem of hypersonic vehicle subject to model parameter uncertainties, external disturbance and input saturation. Firstly, the feedback linearization for longitudinal model of hypersonic vehicle is reasonably decomposed into subsystems that include velocity and altitude subsystem. Secondly, the auxiliary system is introduced to design the anti-saturation adaptive...
This paper studies the heading control of surface vehicles. A novel non-singular terminal sliding mode controller is developed guaranteeing that the vehicle can track the disired heading. Contrasting to the conventional terminal sliding mode control, the proposed algorithm can eliminate of the singularity problem. The proposed controller, not only, can take the vehicle convergence to the desired heading,...
In modern space missions, such as space rendezvous and docking, actuator switching, booster stage separation for carrier rockets, the instantaneous mass or structure variations are exist. A Hamilton system based spacecraft attitude switching control scheme is proposed. The passivity control law is designed based on the Hamilton system model of spacecraft. A dynamic inversion method is used to compensate...
This paper studies the flocking problem for flying robots in three-dimensional space. Each robot's attitude dynamics is considered. Motivated by consensus algorithms, we propose a distributed control law to achieve the flocking of flying robots. The convergence is proved by Lyapunov function and LaSalle's invariance principle. And the simulation results are given to demonstrate the effectiveness of...
This paper presents nonlinear robust trajectory tracking strategies for the hypersonic vehicle whose ailerons are stuck at an unknown angular position. Firstly, a time-varying sliding mode control strategy for general second-order systems is introduced, and the chattering of sliding mode controller is alleviated. Secondly, the dynamics of hypersonic vehicle are transformed into two second-order systems...
In this paper, a novel thrust vectored 3D printed multicopter is designed and built. The dynamic equation of the multicopter with n propellers where n ≥ 2 is derived. Conditions for effective thrust vectoring is established. A robust control scheme for the multicopter system, based on the multi-surface sliding control is proposed. We prove that the proposed control scheme guarantees asymptotic output...
In this paper, we consider a dynamic feedback problem of a pendulum coupled with a viscous damped wave equation. We show that the system operator generates a C0-semigroup of contractions in the energy state space, and the system is well-posed. By giving the asymptotic expressions of the eigenvalues of the system, we know that they all locate in the left hand side of the complex plane. It follows that...
In this paper, the dynamics of a flapping wing vehicle are studied. A quasi-steady model is developed to analyze its aerodynamic forces and moments. The unsteady effects are considered both in hovering state and forward flight state. Different from existing flapping wing vehicle dynamics model, the rudder's dynamics are concurrently considered in the proposed one. Numerical simulation is conducted...
Object of this work is hypersonic cruise vehicle which cruises at Mach number beyond 5 in atmosphere. Range of this vehicle is often restricted by the poor aerodynamic, propulsive and structural performances and severe persistent aerodynamic heating. To extend its range, optimal periodic cruise trajectory has been adopted herein to improve fuel efficiency and remit heat accumulation. The performance...
To solve the problem of optimal path planning of two-wheeled mobile robots (TWMRs) in the presence of dynamic obstacles, a symplectic pseudospectral method for solving nonlinear optimal control problems with inequality constraints is developed. The proposed algorithm transforms the original nonlinear optimal problem into a series of linear-quadratic optimal control problems (LQOCPs) by using quasilinearization...
In order to solve the problem of trajectory optimization of Space Maneuver Vehicle (SMV), a dynamic neural network method is introduced. Combined with neural network and Pontryagin's maximum principle, the method is able to approximate the optimal solution by neural network. At the same time, with the dynamic process, the problem of guessing covariates' initial value in traditional indirect method...
The Approach and Landing (A&L) trajectory optimization is important for reusable launch vehicle (RLV) to deliver it to its landing site safely and reliably. And the trajectory should satisfy multi-constraints and path features. In this paper, the 3D dynamics of RLV in the A&L phase is introduced. and the the adaptive Gauss pseudo-spectral method (AGPM) is used to solve the A&L trajectory...
This paper focuses on solving the Unmanned Surface Vehicle autonomous dynamic collision avoidance problem. Firstly, a kinematic and dynamics model of three degree of freedom for USV is established, researches USV's treat method about the data of obstacles, and structures whole environment information to make USV avoid obstacles. Secondly, according to obstacles' position data, Elman predictive model...
The colored traveling salesman problem (CTSP) is a generalization of the well-known multiple traveling salesman problem (MTSP). In CTSP, each city has one to multiple colors, allowing a salesman in the same color to visit exactly once. This work presents a dynamic CTSP (DCTSP) in which the weights of edges among the cities change over time. To solve the DCTSP, we propose a variable neighborhood search...
Vehicle scheduling plays a crucial role in public transport bus companies. An efficient schedule can help bus companies reduce operating costs while being an essential guide to daily operations. However, the precompiled schedule is usually hard to be adhered to in practice due to the diversity of traffic and driving conditions. Therefore, dynamic vehicle scheduling becomes an important supplement...
In this paper, a robust trajectory tracking control for the underactuated quadrotor unmanned aerial vehicle (UAV) based on extended state observer(ESO) is proposed. In the presence of external disturbances and inner model parameter uncertainty, it guaranteed that the position and yaw angle could track the reference signal speedily and smoothly. According to the strict feedback architecture of the...
In the Underwater Transportation processing, the fixed set-point control of a dynamic positioning system enables an unmanned underwater vehicle (UUV) automatically to move to a set position by means of a control system, as well as to maintain its precision when deviating from that set position. In response, this paper aims to improve its generalization ability by indirectly pruning the structure of...
An in-flight aerodynamic coefficient estimation method is proposed for nonlinear lateral motion of reusable launch vehicle via retrospective cost adaptive control theory. The estimated aerodynamic coefficient is then utilized for adaptive controller switch to cope with unexpected polarity change of LCDP(Lateral Control Departure Parameter) online. First, the nonlinear lateral dynamics of a reusable...
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