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In this paper, a direct current (DC) motor speed control system with proportional-integral-derivative (PID) controller and Kalman filter is presented with consideration of disturbance, system variation, and feedback sensor noise and verified through computer simulations. Initially, a mathematical model for a DC motor system is introduced, after which the performance degradation due to disturbance and system variation in the basic open-loop control is revealed. To resolve this problem, a PID controller based feedback system is designed for the DC motor speed control system. Third, to improve the performance degradation due to feedback sensor noise that may occur during the feedback process, the Kalman filter is applied for the DC motor speed control system. Ultimately, it is verified that the designed DC motor speed control system with PID controller and Kalman filter not only satisfies all performance criteria but also has the ability to reject disturbance, cope with system variation and reduce feedback sensor noise. [ABSTRACT FROM AUTHOR]

State estimation using a filter is one of the fundamental problems encountered in the study of control theory and signal processing for noisy dynamics systems. In this review paper, the finite memory structure (FMS) filter for state estimation is expressed in a variety of forms, such as the iterative form, matrix form, summation form, and smoothing form, using diverse derivation methods for noisy discrete-time state-space models. These diverse derivation methods and expressions can provide a comprehensive understanding of FMS filtering algorithms. Various aspects of FMS filters are characterized. Through discussions, it is demonstrated that the choice of window length can be considered a key design parameter for optimizing the performance of the FMS filter. Simulation results for a noisy discrete-time system indicate that an FMS filter can be better than an infinite memory structure filter for temporarily uncertain systems. [ABSTRACT FROM AUTHOR]

This paper proposes a finite memory structure (FMS) filter for state estimation in time-varying systems with measurement delay, called the TV-FMS filter. By incorporating time-delayed measurements, the proposed TV-FMS filter is obtained by directly solving a weighted least-square cost function. The proposed TV-FMS filter has inherent properties such as unbiasedness, deadbeat, and robustness. Through extensive computer simulations for three kinds of discrete time-varying noisy signal models with a measurement delay as well as an uncertain model parameter, the proposed TV-FMS filter can be shown to be comparable with the Kalman filter with infinite memory structure (IMS) for a nominal system and better than that for a temporarily uncertain system. [ABSTRACT FROM AUTHOR]

In the current paper, a residual generation filter with finite memory structure is proposed for sensor fault detection. The proposed finite memory residual generation filter provides the residual by real-time filtering of fault vector using only the most recent finite measurements and inputs on the window. It is shown that the residual given by the proposed residual generation filter provides the exact fault for noisefree systems. The proposed residual generation filter is specified to the digital filter structure for the amenability to hardware implementation. Finally, to illustrate the capability of the proposed residual generation filter, extensive simulations are performed for the discretized DC motor system with two types of sensor faults, incipient soft bias-type fault and abrupt bias-type fault. In particular, according to diverse noise levels and windows lengths, meaningful simulation results are given for the abrupt bias-type fault. [ABSTRACT FROM AUTHOR]

In this paper, an alternative IEEE 802.21-assisted Proxy Mobile IPv6 (PMIPv6) mechanism is proposed for reducing handover latency and signaling cost in heterogeneous wireless networks. The proposed mechanism comes to support fast vertical handover for the mobile node (MN) irrespective of the presence or absence of Media Independent Handover (MIH) functionality as well as IP mobility functionality. That is, the MN does not need to be participated in any MIH related signaling for handover procedure, which can be consistent with the essential objective of the PMIPv6. The base station with MIH functionality performs handover on behalf of the MN. Therefore, the proposed mechanism can reduce burden and power consumption of MNs with limited resource and battery power. In addition, analytical evaluation, experiment and simulation show that the proposed mechanism can outperform the existing mechanism in terms of handover latency and total number of over-the-air signaling messages. Thus, the proposed mechanism can be expected to reduce the packet loss and the bandwidth consumption of wireless links during handover procedure comparing with the existing mechanism. [ABSTRACT FROM AUTHOR]

Proposes a separate-bias estimation scheme for systems with diversely behaved biases. Consequences of unknown bias; Types of typical behaviors of the bias; Development of the model; Results of the numerical simulation performed.