Automatika 

About: Automatika is an academic journal published by Taylor & Francis. The journal publishes majorly in the area(s): Computer science & Control theory (sociology). It has an ISSN identifier of 0005-1144. It is also open access. Over the lifetime, 534 publications have been published receiving 3640 citations.

VCL@FER Image Quality Assessment Database

Abstract: In this paper we present new image quality database VCL@FER (http://www.vcl.fer.hr/quality/) which consists of four degradation types, 6 levels of each degradation and 23 different images (552 degraded images). It can be used in objective image quality evaluation, as well as to develop and test new image quality measures. Results for six commonly used full reference objective quality measures are compared using newly developed image database, as well as 6 other image databases.

Distributed Maximum Power Point Tracking in Photovoltaic Systems—Emerging Architectures and Control Methods

Abstract: The interest in distributed maximum power point tracking increases along with increasing deployment of photovoltaic generators and the constant pressure to reduce the cost of photovoltaic generated...

A Low-Noise Estimator of Angular Speed and Acceleration from Shaft Encoder Measurements

Abstract: In the field of robotics and automation, the main objective of motion control is to guarantee accurate tracking of position or speed trajectories characterized by large harmonic content. In order to achieve this purpose, a cascade structure for the controller is usually adopted. This architecture is constituted by »nested« control loops: the outer position and speed control loops and the inner »effort« control loop [1, 2]. The outer loops mainly deal with the mechanical part of the plant, while the inner loop controls the actuator producing the effort which »moves« the system (generally an electric motor which produces torque). It is well known that the action yielded by these controllers can be split in two main parts: the feedforward one and the feedback one. The former is based on the »inversion« of the nominal dynamical model of the plant and mainly determines a fast response to reference variations. The latter is based on measurements and should make the tracking performance robust with respect to all the non-idealities, as parameter uncertainties and unexpected loads. Since the model of the controlled system and the knowledge of external loads are often quite rough, the tracking performances are essentially related to the feedback control characteristics. In order to obtain feedback controllers with wide bandwidth (i.e.

Design for sensorless force control of flexible robot by using resonance ratio control based on coefficient diagram method

Abstract: Generally, the flexible robot system can be modeled as the two-mass system which consists of a motor and load connected by a spring. Thus, its elasticity causes resonance in the system. By using the conventional PID controller, this method cannot perform well in this situation. Much research has proceeded with the aim of reducing vibration. A new effective control method, the resonance ratio control, has been introduced as a new way to guarantee the robustness and suppress the oscillation during task executions for a position and force control. In this paper, three techniques are proposed for improving the performance of resonance ratio control: Firstly, A new multi encoder based disturbance observer (MEDOB) is shown to estimate the disturbance force on the load side. The proposed observer is not necessary to identify the nominal spring coefficient. Secondly, coefficient diagram method (CDM) has been applied to calculate a new gain of the force controller. A new resonance ratio gain has been presented as 2.0. Finally, the MEDOB and load side disturbance observer (LDOB) are employed to identify a spring coefficient of flexible robot system. By using the proposed identification method, it is simple to identify the spring coefficient and easy to implement in the real flexible robot system. The effectiveness of the proposed identification method is verified by simulation and experimental results.

Optimized cluster head selection using krill herd algorithm for wireless sensor network

Abstract: Wireless Sensor Network (WSNs) can perform transmission within themselves and examination is performed based on their range of frequency. It is quite difficult to recharge devises under adverse con...