This paper concerns disturbance rejection for a repetitive-controlsystem(RCS) with unknown time-varying uncertainties and nonlinearity. The design of the RCS is based on the concept of equivalent input disturbance...
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ISBN:
(纸本)9781538629185
This paper concerns disturbance rejection for a repetitive-controlsystem(RCS) with unknown time-varying uncertainties and nonlinearity. The design of the RCS is based on the concept of equivalent input disturbance(EID). First, an EID estimator is constructed through a state observer with dynamic coefficient matrix that effectively estimates the total effect of the uncertainties and nonlinearity on the output of the plant. Next, a robust globally uniformly ultimately bounded stability condition for the EID-based RCS is derived in the form of a linear matrix inequality. Then, the methods of designing a modified repetitive controller, a state-feedback controller, and an EID estimator are explained. Finally, simulation results demonstrate the validity of the method.
Piezoelectric geophones are vibration detectors that convert vibration acceleration signals into electrical signals. High performance piezoelectric materials can improve the sensitivity of piezoelectric geophone and m...
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Piezoelectric geophones are vibration detectors that convert vibration acceleration signals into electrical signals. High performance piezoelectric materials can improve the sensitivity of piezoelectric geophone and meet the need of high-resolution seismic data acquisition. The comprehensive performance of relaxor piezoelectric single crystal PMN-PT is more superior than PZT, and it is potential to be applied to high sensitivity and small volume geophones. In this paper, the central compressed geophone core model based on PMN-PT was established and theoretically analyzed. Then, a multiphysics simulation model was set up in COMSOL for simulation calculation. Finally, experimental verification was carried out. The results show that using PMN-PT in geophone core design can improve the sensitivity of the model by more than 120% compared with the traditional PZT material. The PMN-PT has the potential to be applied to high sensitivity and small volume geophones.
An autonomous approach and landing(A&L) guidance law is presented in this paper for landing an unpowered reusable launch vehicle(RLV) at the designated runway touchdown. Considering the full nonlinear point-mass ...
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An autonomous approach and landing(A&L) guidance law is presented in this paper for landing an unpowered reusable launch vehicle(RLV) at the designated runway touchdown. Considering the full nonlinear point-mass dynamics, a guidance scheme is developed in threedimensional space. In order to guarantee a successful A&L movement, the multiple sliding surfaces guidance(MSSG) technique is applied to derive the closed-loop guidance law, which stems from higher order sliding mode control theory and has advantage in the finite time reaching *** global stability of the proposed guidance approach is proved by the Lyapunov-based *** designed guidance law can generate new trajectories on-line without any specific requirement on off-line analysis except for the information on the boundary conditions of the A&L phase and instantaneous states of the RLV. Therefore, the designed guidance law is flexible enough to target different touchdown points on the runway and is capable of dealing with large initial condition errors resulted from the previous flight phase. Finally, simulation results show the effectiveness of the proposed guidance law in different scenarios.
Ant colony optimization (ACO) has been shown effectiveness for solving combinatorial optimization problems. Inspired by the basic principles of ACO, this paper proposes a novel evolutionary algorithm, called probabili...
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Intersection detection is a critical capacity for an Unmanned Ground Vehicle (UGV) to drive safely in structured urban environment. Large-scale intersections stamped on maps have plenty of features for detection while...
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Due to the limited visual field of UGV, it is difficult to detect the accessible zone in a wide range of area in real time. This paper proposes a UAV-aided autonomous road network construction method where roads are p...
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A single satellite navigation system can get high accuracy in general environment, but when the ground satellite navigation receiver is in complex environment, single system navigation often results in poor location r...
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A single satellite navigation system can get high accuracy in general environment, but when the ground satellite navigation receiver is in complex environment, single system navigation often results in poor location results due to the visible satellite less than four. If multiple constellation fusion navigation is used, the number of visible satellites can be increased, thus improving the positioning results. However, the use of all visible satellites in location calculation will bring a huge amount of calculation, which seriously affects the real-time performance of navigation and positioning. Therefore, a reasonable selection of star selection method is urgently needed in the integrated navigation system. Based on the two performance indexes of balanced geometric accuracy factor (GDOP) and star selection efficiency, fast star selection algorithm based on equivalent distance error is proposed in this paper. The experimental results show that the method can effectively improve the efficiency of multi constellation star selection of the premise of high precision.
The design and implementation of a monitoring system for networked controlsystems (NCSs) are introduced in this paper. The monitoring system is developed in the .NET framework using C# according to the C/S architectu...
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The design and implementation of a monitoring system for networked controlsystems (NCSs) are introduced in this paper. The monitoring system is developed in the .NET framework using C# according to the C/S architecture which allows the user to monitor network nodes without geographical limitations. The widgets used to display come from the National Instruments (NI) suit and are integrated in the system by reconstructing it. The user is able to design a monitoring interface freely by creating and customizing widgets dynamically. During the monitoring, the display value of the widget is synchronized with parameters and signals of NCSs through receiving data asynchronously from network notes. In particular, all elements of the matrix widely used in NCSs are supported for monitoring. The functionality and feasibility of the designed monitoring system are demonstrated via a networked control experiment. In addition, the saved data can be used in data driven control and model identification.
This paper concerns the stability analysis of discrete Takagi-Sugeno fuzzy systems with time-varying delays. A suitable Lyapunov-Krasovskii functional is constructed, and an extended reciprocally convex matrix inequal...
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This paper concerns the stability analysis of discrete Takagi-Sugeno fuzzy systems with time-varying delays. A suitable Lyapunov-Krasovskii functional is constructed, and an extended reciprocally convex matrix inequality is used to estimate the forward difference of the functional. As a result, a less conservative stability criterion is obtained. Finally, a numerical example is given to demonstrate the advantage of the proposed method.
Stroke is mainly caused by the brain damage due to the acute cerebral vascular disease and its primary disease,which can make upper limb or lower limb on one side of the body *** rehabilitation training is the most ef...
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ISBN:
(纸本)9781509046584
Stroke is mainly caused by the brain damage due to the acute cerebral vascular disease and its primary disease,which can make upper limb or lower limb on one side of the body *** rehabilitation training is the most effective way to regain the Activities of Daily Living(ADL).Based on the concept of humanoid and modular design,this paper outlines the design process of humanoid ***,kinematics and dynamics are calculated in different coordinate frames,which makes simulation and control algorithms are more complex and not intuitive,for the forked-tree structure rehabilitation robot,a modified geometric description method of DH parameters is proposed to solve the problem of inconsistent frames,the whole body Jacobian matrix of this structure is derived and used for the inverse kinematics,and the singular configurations of redundant manipulator are *** important design criteria of humanoid robot is discussed,and the realization of the mechanical design is ***,the experimental results show that the humanoid robot can effectively carry out multiple parts rehabilitation training.
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