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This paper presents a self-memory prediction model to mitigate the effects of image based visual servoing (IBVS) system under uncertainty. The performance of IBVS system is easily influenced by different tasks, diverse environments and uncertain disturbances. Through building a self-memory prediction model to keep previous movement tendency in the every current movement, the framework of a self-memory...
The impulse-based discrete feedback control has been proposed in previous work for the second-order motion systems with damping uncertainties. The sate-dependent discrete impulse action takes place at zero crossing of one of both states, either relative position or velocity. In this paper, the proposed control method is extended to a general hybrid motion control form. We are using the paradigm of...
A new detection algorithm for direct sequence spread spectrum (DSSS) signals using peak-to-average power ratio (PAPR) is proposed. The received signals are divided into several blocks. Then we calculate peak-to-average power ratio of each block and we use the average of peak-to-average power ratios as test statistics. The advantage of the proposed algorithm is no need to estimate noise variance. Additionally,...
In this paper, a neural network based adaptive state feedback control scheme is proposed to solve the problem of trajectory tracking in the joint space for robotic manipulators with the presence of high uncertainty in the system parameters. First nonlinear behavior of the robot is approximately eliminated by applying a linearizing control, the closed loop dynamics is stabilized using static compensator...
A large number of testing procedures have been developed to ensure vehicle safety in common and extreme driving situations. However, these conventional testing procedures are insufficient for testing autonomous vehicles. They have to handle unexpected scenarios with the same or less risk a human driver would take. Currently, safety related systems are not adequately tested, e.g. in collision avoidance...
Quantum key distribution (QKD) enables two authenticated parties to share secret keys with the ability to detect any attempts to eavesdrop the keys theoretically. Currently, QKD systems can be categorized by its source of uncertainty in nature; single photon or coherent light. As coherent light is harnessed, the overall cost for composing systems drops in general. However, more elaborate post processing...
We investigate the filter design problem for discretetime interval uncertain positive systems under the ℓ1 performance in this paper. First, we propose some conditions expressed by linear programming to ensure the asymptotic stability and the ℓ1 performance for given positive systems. Then, we establish a novel filter design approach and an iterative algorithm to obtain the desired filter for interval...
In this paper, a problem of robust fault detection for uncertain networked control system (NCS) including random data packet loss is investigated. This NCS is established as a stochastic system with norm-bounded uncertainty, in which the stochastic variable is followed by Bernoulli distribution. Then, a robust fault detection filter (FDF) is designed based on the observer method, which is obtained...
Conventional sliding mode control (SMC) is so-called robust to the system uncertainty and the external disturbance, however, it requires the knowledge about the upper bound of uncertainties and external disturbances. In the practical system, uncertainties and external disturbances are often unknown. A adaptive backstepping sliding mode controller (ABSMC) is proposed to deal with the uncertainty in...
Degradation reliability prediction under stochastic failure threshold is studied. The explicit expression of reliability is derived, by charactering the uncertainty of failure threshold with probability distribution. Then, a possibilistic approach for reliability modeling and prediction for degrading components is presented, by use of possibility distribution.
Annotating human poses in realistic scenes is very time consuming, yet necessary for training human pose estimators. We propose to address this problem in an active learning framework, which alternates between requesting the most useful annotations among a large set of unlabelled images, and re-training the pose estimator. To this end, (1) we propose an uncertainty estimator specific for body joint...
We develop Bayesian algorithms to perform realtime positioning and uncertainty quantification on Global Positioning System (GPS) data. We test the algorithms on GPS data from several global locations and score their predictions using the log-score. The best algorithm is a Kalman filter that assumes an Ornstein-Uhlenbeck (OU) noise model. The OU model accounts for the observed autocorrelated process-noise...
A DC/DC boost converter exhibits highly nonlinear properties and subjects to certain uncertainties, like load change, input voltage variation, and parametric uncertainties. This paper first presents an improved accurate model of the converters, including the parasitic elements and model uncertainties, which are usually existed in actual systems but not (or not sufficiently) considered in most of the...
The problem of spacecraft attitude tracking control for actuator faults/failures and external disturbances is addressed in this paper. Assuming that information on external disturbances is unknown, a finite time sliding mode (FTSM) control law is developed to handle actuator faults/failures. Under the constraint conditions including the actuator faults and external disturbance, stability analysis...
The flexible joint robot manipulators provide various benefits, but also present many control challenges such as nonlinearities, strong coupling, vibration, etc. This paper proposes optimal second order integral sliding mode control (OSOISMC) for a single link flexible joint manipulator to achieve robust and smooth performance. Firstly, the integral sliding mode control is designed, which consists...
This paper is concerned with the problem of stabilization and tracking for a class of underactuated systems subjected to external disturbances. Based on the mathematical model of a 4 degrees of freedom (4DOF) ball and plate system, a robust backstepping controller with disturbance rejection is developed. The proposed controller is capable of handling bounded uncertainties with unknown periodicity...
In this work, the control problem for type-2 T-S fuzzy system with packet dropouts is investigated by modeling the system as a switched system with an unstable subsystem. The mode-dependent average dwell time approach in both slow and fast switching sense is utilized for the analysis and synthesis. A sufficient condition is given by ensuring the packet loss rate no bigger than the specific fast switching...
Presented in this paper is grid current observer-based compensation control for a single-phase grid-connected inverter that is connected to a weak grid. Traditional single-loop PI current control performance suffers in the presence of the grid voltage distortion and grid impedance uncertainty. To compensate for disturbances from the grid side, two different compensation control structures are proposed...
This paper presents an adaptive nonsingular terminal sliding mode formation control by means of output recurrent fuzzy wavelet neural networks for a group of networked heterogeneous Mecanum-wheeled omnidirectional robots with uncertainties. The dynamic behavior of each uncertain heterogeneous omnidirectional robot is modelled by a reduced three-input-three-output second-order state equation with uncertainties...
The paper is concerned with the robust finite-time stabilization problem of quadrotors subject to inertia uncertainty and disturbances. The underlying stabilization problem consists of controller designs for position loop and attitude loop, both of which are carried out based on the terminal sliding mode control approach. First, a robust finite-time position controller is designed by considering the...
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