Accurate and fast visual localization is required in many applications of mini-robotics. Obtaining the best possible result fora given platform requires a balanced combination of camera settings and efficient image processing of the acquired image. Inthis paper, we study the trade-off betwee...

Purpose – The purpose of this paper is to present the calibration of a laser welding model suitable for solving problems with input data that are either unknown or known only approximately. Design/methodology/approach – The calibration starts from the measured temperature profile&#...

Purpose – This paper aims to propose a number of approaches to reduce the temperature gradient of titanium billets in the heat treatment process. Design/methodology/approach – Modeling physical processes in the induction unit is calculated by the finite element method. Required pow...

A magnetic and nonlinear structural mechanic coupled problem is discussed concerning the behaviour of a magnetorheological elastomer. Material properties and hyperelastic character of the material were found by measurements. Based on the measurements and computations, a coupled mathematical model is&#...

A novel technique of optimizing selected models of electroheat processes (laser or induction-assisted laser welding, cladding, and so on) is presented, based on the calibration of temperature-dependent material properties. These properties often exhibit uncertainties that negatively influence the quality&#...

Purpose – The paper aims to describe the modeling of the induction-assisted laser welding process taking into account the keyhole effect and phase changes in the material. Design/methodology/approach – A sophisticated mathematical model of the above heat treatment process is presented,&...

Possibilities of using surrogate techniques for modeling selected strongly nonlinear coupled problems of heating are evaluated. The main purpose is to significantly reduce the computing time in the case of computations of many variants of a given task by the finite element method o...

The paper deals with a problem of modeling of dynamic systems. The proposed approach to the problem solution is based on modified Tellegen’s theorem well known from electrical engineering. The novelty of this approach is that it is based on the instantaneous power calculation ...

The following topics are dealt with: artificial satellites; CMOS integrated circuits; switching convertors; reliability; DC-DC power convertors; failure analysis; oscillators; capacitors; solar power satellites; network topology.

This paper deals with dissipativity, stability, chaotic behavior and related structural properties of a relatively broad class of finite dimensional strictly causal systems. The class of nonlinear systems under consideration is described in the state-space representation form. System properties are&#x...

A method of finding the temperature dependences of physical parameters of metals is proposed and discussed. The method is based on the combination of measurement of the surface temperature of the material and subsequent solution of the inverse problem using the multi-parametric optimiza...

The article is devoted to the physical nature of geomagnetism, magnetic storms and methods of predicting their origin and deals with geomagnetic induced currents called GIC (Geomagnetically Induced Currents) and their effect on power transformers. A simplified, single-phase transmission system is...

A model of hybrid cladding on a cylindrical surface is built and numerically solved. Heating of both substrate and the powder material to be deposited on its surface is realized by laser beam and preheating inductor. The task represents a hard-coupled electromagnetic-thermal problem...

In most publications eddy current testing (ECT) methods are said to be suitable for surface defects up to several millimeters. This paper aims to evaluate the detection capabilities of eddy current testing based on two examples of modern approach. One of them is a harmonic...

Novel approach to modeling of 3D coupled electroheat problems with time-varying geometries is presented. Instead of time-expensive remeshing of the whole system in every time step it is used the initial mesh that takes into account the expected geometric changes. In the course of&#...

Autonomous wireless body-implanted devices for biotelemetry, telemedicine, and neural interfacing constitute an emerging technology providing powerful capabilities for medicine and clinical research. We study the through-tissue electromagnetic propagation mechanisms, derive the optimal frequency range, and obtain th...

Purpose: A model of hybrid fillet welding is built and solved. No additional material (welding rod, etc.) is used. Heating of the welded parts is realized by laser beam with induction preheating and/or postheating. The purpose of these operations is to reduce the temperature&#...

Purpose: A novel technique for control of complex physical processes based on the solution of their sufficiently accurate models is presented. The technique works with the model order reduction (MOR), which significantly accelerates the solution at a still acceptable uncertainty. Its advanta...