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In the paper a comparison between the analytical and numerical method of no‐load computation will be made taking into account the initial hypothesis and computational effort face to the concrete obtainable results. It is concluded that the reduced fixed‐mesh FEM analysis of the induction motors is very suitable for no‐load computation because it relates directly to the well known equivalent circuit parameters. The symmetry of the machine allows for the computation only on a small part of the magnetic circuit so that the time of computation can be reduced even when a relatively fine mesh is used. However, for the optimal design of the motor it appears that analytical methods are very suitable owing to the simplicity and accuracy of the design.

The purpose of this paper is to present a finite element model capable of describing both the diffuse damage mechanism which develops first during the loading of massive brittle structures and the failure process, essentially due to the propagation of a macro‐crack responsible for the softening behaviour of the structure. The theoretical developments for such a model are presented, considering an isotropic damage model for the continuum and a Coulomb‐type criterion for the localized part.

This is achieved by activating subsequently diffuse and localized damage mechanisms. Localized phenomena are taken into account by means of the introduction of a displacement discontinuity at the element level.

It was found that, with such an approach, the final crack direction is predicted quite well, in fact much better than the prediction made by the fracture mechanics type of models considering combination of only elastic response and softening.

The presented model has the potential to describe complex damage phenomena in a cyclic and/or non‐proportional loading program, such as crack closing and re‐opening, cohesive resistance deterioration due to tangential sliding, by using only a few parameters compared to the traditional models for cyclic loading.

An efficient perception of the complex environment is the foremost requirement in mobile robotics. At present, the utilization of glass as a glass wall and automated transparent door in the modern building has become a highlight feature for interior decoration, which has resulted in the wrong perception of the environment by various range sensors. The perception generated by multi-data sensor fusion (MDSF) of sonar and laser is fairly consistent to detect glass but is still affected by the issues such as sensor inaccuracies, sensor reliability, scan mismatching due to glass, sensor model, probabilistic approaches for sensor fusion, sensor registration, etc. The paper aims to discuss these issues.

This paper presents a modified framework – Advanced Laser and Sonar Framework (ALSF) – to fuse the sensory information of a laser scanner and sonar to reduce the uncertainty caused by glass in an environment by selecting the optimal range information corresponding to a selected threshold value. In the proposed approach, the conventional sonar sensor model is also modified to reduce the wrong perception in sonar as an outcome of the diverse range measurement. The laser scan matching algorithm is also modified by taking out the small cluster of laser point (w.r.t. range information) to get efficient perception.

The probability of the occupied cells w.r.t. the modified sonar sensor model becomes consistent corresponding to diverse sonar range measurement. The scan matching technique is also modified to reduce the uncertainty caused by glass and high computational load for the efficient and fast pose estimation of the laser sensor/mobile robot to generate robust mapping. These stated modifications are linked with the proposed ALSF technique to reduce the uncertainty caused by glass, inconsistent probabilities and high load computation during the generation of occupancy grid mapping with MDSF. Various real-world experiments are performed with the implementation of the proposed approach on a mobile robot fitted with laser and sonar, and the obtained results are qualitatively and quantitatively compared with conventional approaches.

The proposed ASIF approach generates efficient perception of the complex environment contains glass and can be implemented for various robotics applications.

The purpose of this study is the introduction of finite permeability of ferromagnetic core in analytical approach for slotted spoke-type permanent magnet machine.

A two-dimensional analytical approach of magnetic field distribution is established for spoke-type permanent magnet machine to calculate the flux density distribution in the middle of airgap. The paper presents an analytical subdomain model accounting for stator slotting effect. The governing equations are obtained from Maxwell’s equations by using vector potential in all regions of the machine, i.e. magnet, airgap, stator slots and rotor/stator yoke. The finite element analysis is used to validate the analytical results.

It is found that the developed subdomain model including finite permeability of ferromagnetic core is accurate and is applicable for spoke-type permanent magnet machine for no-load and on-load condition. The analytical results are in accurate agreement with the numerical simulation.

Some assumptions and conditions are presented to improve and simplify the analytical method for analyzing the global saturation for spoke-type permanent magnet machine.

The aim of this paper is to prove that the manipulator is able to contact the environment compliantly, and reduce the instantaneous collision impact.

Cartesian impedance control law is introduced to interrelate the external force with the Cartesian position.

When the estimated external force sensor feedback is the input of the on‐line trajectory regeneration, a novel online motion plan could be performed in a task‐consistent manner keeping the interaction force within the acceptable tolerance. The proposed approach also proves that the manipulator is able to contact the environment compliantly, and reduce the instantaneous collision impact. The virtual decomposition control, simplifying the Cartesian impedance control application of the manipulator and guaranteeing the asymptotical stability of the entire system, is implemented to actualize the approach. Furthermore, adaptive dynamics joint controller is extended to all the joints for complementing the biggish friction.

With the proposed adaptive Cartesian impedance control and the online path planner, the robot will be manipulation‐friendly in an unstructured environment.

Construction projects involve with various risks during all phases of project lifecycle. Failure mode and effective analysis (FMEA) is a useful tool for identifying and eliminating possible risk of failure modes (FMs) and improving the reliability and safety of systems in a broad range of industries. The traditional FMEA method applies risk priority number method (RPN) to calculate risk of FMs. RPN method cannot consider the direct and indirect interdependencies between the FMs and is not appropriate for complex system with numerous components. The purpose of this study is to propose an approach to consider interdependencies between FMs and also using fuzzy theory to consider uncertainties in experts' judgments.

The proposed approach consist of three stages: the first stage of hybrid model used fuzzy FMEA method to identify the failure mode risks and derive the RPN values. The second stage applied Fuzzy Decision-Making Trial and Evaluation Laboratory (FDEMATEL) method to determine the interdependencies between the FMs which are defined through fuzzy FMEA. Then, analytic network process (ANP) is applied in the third stage to calculate the weights of FMs based on the interdependencies that are generated through FDEMATEL method. Finally, weight of FMs through fuzzy FMEA and FDEMATEL–ANP are multiplied to generate the final weights for prioritization. Afterward, a case study for a commercial building project is introduced to illustrate proficiency of model.

The results showed that the suggested approach could reveal the important FMs and specify the interdependencies between them successfully. Overall, the suggested model can be considered as an efficient hybrid FMEA approach for risk prioritization.

The originality of approach comes from its ability to consider interdependencies between FMs and uncertainties of experts' judgments.

This paper gives a bibliographical review of the finite element and boundary element parallel processing techniques from the theoretical and application points of view. Topics include: theory – domain decomposition/partitioning, load balancing, parallel solvers/algorithms, parallel mesh generation, adaptive methods, and visualization/graphics; applications – structural mechanics problems, dynamic problems, material/geometrical non‐linear problems, contact problems, fracture mechanics, field problems, coupled problems, sensitivity and optimization, and other problems; hardware and software environments – hardware environments, programming techniques, and software development and presentations. The bibliography at the end of this paper contains 850 references to papers, conference proceedings and theses/dissertations dealing with presented subjects that were published between 1996 and 2002.

The purpose of this paper is to discuss the calculation problem of the real carrying capacity of slewing bearings. The selection of slewing bearing to heavy-duty machine according to catalogue carrying capacity and also according to locally determined real carrying capacity is insufficient and it can be the cause of the damage of machine during exploitation.

The concepts of the local, total and general capacities is defined. The general capacity is a logical product of the local capacities. It is particularly useful in an analysis of slewing bearings incorporated into machines with complex structures. The FEM is applied in computations. The formation method of the mathematical model of a bearing is presented.

The computations of the local capacities and general capacity of a bearing for the limiting load of the bearing traces and the limiting tension of the bolts fastening the bearing were carried out. Considerations were illustrated by an example of the bearing of a mobile crane.

The paper presented in the methodology of the calculation of general bearing carrying capacity and the obtained results of calculations can be used already by designers of bearings and machine engines to elimination of the potential damages of machine on the stage of projecting.

The general capacity of a bearing into machines with complex and irregulars structure is considerably lower than the bearing catalogue capacity and then the local teal capacity. The reasons for the differences between the catalogue capacity and the general capacity of slewing bearings were given.

The analysis, carried out for this publication, concerned checking the nature of mating of gear wheels with different load conditions. The computation was made applying FEM in Abaqus 6.10-1 program and concerned spur gears in dual-power-path gears made of ABS. The same geometrical models, material parameters and boundary conditions were assumed for all the analysed stages of the computation. However, the values of torque transmitted from active wheels to passive wheel of the gearing were changed. The paper aims to discuss these issues.

Observing changes of stress levels for toothed wheel and pinions allows to state that for relatively low load values, bending stresses at tooth root change proportionally to the change of the applied load.

Values of contact stresses on mating teeth flanks were also defined for the most loaded part of the dual-power-path gearing, namely for a pinion. In case of contact stresses, it was observed that together with constant increase of torque value, the values of stresses change but the nature of these changes is not proportional to the applied load. Out of all the analysed variants, the most favourable, from the point of view of durability, was the situation in initial (theoretical) model with regular power division on all mating wheels.

Conclusions drawn as a result of numerical computation are helpful in defining the nature of work of dual-power-path gearing in different load conditions and will be compared to results of stand tests of the analysed gearing.

A fully parallel algorithm for the solution of a finite element system using a MIMD (multiple‐instruction multiple‐data architecture) parallel computer is presented. The formulation includes a simple domain decomposer that automatically divides a finite element mesh into a list of subdomains to guarantee the load balancing. Furthermore, each subdomain is assigned to a processor of a parallel computer and treated as a sub‐finite element system with information exchanged through the interface between two adjacent subdomains. With this new algorithm, these sub‐finite element systems are solved fully parallelly as independent finite element systems, not only the computations of the interior nodes but also the computations of the interface nodes can be executed parallelly. Also, the inherently sequential Gauss‐Seidel and SOR schemes are altered into fully parallel iterative schemes. An implementation of this new scheme on an iPSC/2 D5 Hypercube Concurrent Computer reached an efficiency of more than 100% when compared with the sequential SOR scheme.