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Because it is hard to depict real world traces, researchers proposed some mobility models in the study of mobile ad-hoc networks. It is aware recently that some mobility models will lead to non-uniform node distribution, which decreases the credibility and validity of simulations. Many researchers reconsider the node distribution characteristic for random waypoint model and have gotten some valuable...
In practice, robot systems are usually required to hold uncertain load whose mass may change around a certain value. In this paper, the stability of the conventional model-based Computed-Torque Control(CTC) scheme for delta robots with uncertain load is investigated. Moreover a compensation control scheme is proposed to enhance the robustness of the conventional CTC scheme. The overall control is...
For the problem of ideal steering ratio design of vehicle steer-by-wire system, the design method that based on constant yaw rate gain is researched in this paper. The vehicle model of steer-by-wire is built based on the co-simulation of CarSim and Matlab/Simulation. According to the design principle of the ideal steering ratios, the ideal steering ratios in different speed and different steering...
In this paper, a new mathematical model is built according to the characteristics of the BLDC motor and a new filtering algorithm is proposed for sensorless brushless DC (BLDC) motor based on Unscented Kalman Filter(UKF). The proposed UKF algorithm is employed to estimate the speed and rotor position of the BLDC motor only using the measurements of terminal voltages and three-phase currents. In order...
This paper is concerned with the calculation of the index weights for seafarers' competency evaluation model. The goal of our work is to obtain the reasonable index weight for the evaluation model. In this paper, firstly, the fuzzy comment data is prepared according to the fuzzy linguistic terms, and the intuitionistic fuzzy decision matrix is built. Secondly, base on the minimum intuitionistic fuzzy...
The delay-dependent finite-time H∞ control matter of the uncertain nonlinear neutral time-delayed systems via output feedback is considered. The uncertain disturbance is assumed to energy bounded. By selecting an appropriate Lyapunov function, a finite-time bounded H∞ control criterion is provided for the closed-loop neutral system by the way of the linear matrix inequalities (LMIs). Emulation consequents...
This paper proposes a new analytical method to determine the series resistance Rs of solar cells. This method is based on the exponential function of characteristic equation and results are evaluated from the experimental data. The parameter model of series resistance Rs proposed in this paper and other four parameter models (the shunt resistance Rsh, the saturation current Is, the photo current density...
As the process of traditional dynamics modeling for rigid-flexible couple system is complex, this paper introduces the theory of characteristic modeling to simplify the modeling process. Unlike other reduced-order models, characteristic model compresses the high-order information into the characteristic parameters. Therefore, it will not lose model information. In addition, in order to improve the...
For the complex spacecraft with large flexible accessories, suppressing the flexible vibration is a significant problem. Based on singular perturbation theory, the combination control method is proposed, which associates nonlinear PID controller and linear quadratic controller by dividing spacecraft dynamics equations into slow-change subsystem and quick-change subsystem. The slow-change subsystem...
This paper concerns with the dynamics of TH equations both in the time domain and in the true anomaly domain. Based on the homogeneous solutions of TH equations, a state transition matrix for the TH equations in the true anomaly domain is obtained. The state transition matrix applies to any eccentric orbit. Through the state transition matrix, the sampleddata descriptions are obtained for both the...
The integrated guidance and control (IGC) technology of aircraft has been developing for more than 30 years, and it mainly focused on the research in single plane. Due to the exigent requirement on the three-dimensional IGC technology in current researches, the mathematical modeling in three-dimensional space is considered and analyzed in order to solve the primary problem during the design period...
In this paper, robust actuator fault reconstruction for satellite attitude control systems (ACSs) in the presence of space environmental disturbances and actuator faults is investigated via a learning observer (LO). First, a nonlinear mathematical model of the satellite ACS satisfying Lipschitz constraint is established; then an LO is constructed to achieve robust reconstruction of satellite attitude...
This paper introduces a method to control a two-wheeled self-balancing robot based on Kalman filter and LQR algorithm. It is incorporated with hardware design, signal processing and control algorithm design. In this system the angle signals from a gyroscope and an accelerometer, disposed by Kalman filter, are combined with LQR controller to accomplish the controlling of the robot. The purpose of simplifying...
This paper presents a new adaptive optimal control which is based on a particular hybrid systems called piecewise linear continuous systems. This referred proposed controller which is based on a L2 norm prescribed to minimize a tracking error and a time-delay estimation technique is developed from model based and finally can be applied to systems without knowing internal dynamics. Thus this proposed...
In this paper, orbit interception correction strategy using fixed-time constraints is considered. This work developed an optimal method for the problem based on the linear quadratic with discrete-time impulsive control. The linearized model was set up using the perturbation guidance equation, and the control system model was simplified. The control strategy was obtained by discrete impulsive optimization...
On the basis of the establishment of articulated truck model and hydraulic steering system model, this paper establishes optimal direct yaw moment control strategy based on the main and auxiliary control variables. The main control variables are side slip angle and yaw rate of vehicle, and the auxiliary control variable is the articulated angular acceleration. The handling and stability of articulated...
An anisotropic swarm model with a new attraction and repulsion function is considered in this paper. It is shown that, when the coefficient matrix is symmetric, the swarm members will aggregate and eventually form a cohesive cluster around the swarm center. Moreover, the swarm system is completely stable and the swarm center keeps still for all time. Numerical simulations agree well with the theoretical...
In this paper, a new 5-DOF spacecraft simulator which is a frictionless environment simulation platform is described. The simulator has two translational degrees of freedom and three rotational degrees of freedom. It is used for experimental validation of various spacecraft control strategies on the ground. A set of three inertial wheels and a set of sixteen cold-gas thrusters are used as primary...
To obtain the attitude of spacecraft by a large field of view CCD system is not an unachievable task. The principal aim of this paper is to research the accuracy of spacecraft's attitude by shooting stars with the large field of view CCD system on the ground. In this paper, the quadrilateral algorithm model and an algorithm of data fusion from a set of real images, are given. The experimental results...
A smoothing neural network (SNN) can be proposed for solving a kind of constrained convex problems, which has wide applications in image restoration. The optimization model is a nonsmooth convex problem with convex constraint defined by a class of affine equalities. Thanks to the smoothing methods, the SNN can be modeled by a differential equation instead of a differential inclusion and it can be...
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