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Wheel‐terrain interaction has hardly been taken into consideration in the process of conventional mobile robot design, but its importance has been reflected increasingly towards these categories of mobile robots in rough sandy terrain or obstacle‐dense ground, as the first performance index in this situation is the trafficability of robot whose propulsion is uniquely generated by wheel‐terrain interaction. Consequently, it is valuable to find an optimized design method when the terrain and robot itself are regarded simultaneously. The purpose of this paper is to present a novel and reasonable design approach to mobile robot in sandy terrain.

Leading to some conflicted performance indices of robot, terramechanics describes the non‐linear characteristics in wheel‐terrain interaction mathematically, therefore, trade‐offs must be implemented to get a proper solution by multi‐objective optimization (MOO). In this paper, a five‐wheeled drive and five‐wheeled steering (5WD5WS) reconfigurable mobile robot is taken as demonstration with taxonomy of total‐symmetrical, partial‐symmetrical and asymmetrical prototypes. After function modeling, the MOO is carried out via iSIGHT‐FD using NCGA (Neighborhood Cultivation Genetic Algorithm) to minimize the mass, wheel resistance and maximize the static stability simultaneously.

After MOO, a compact and light weighted asymmetrical prototype is obtained with better trafficability, and other prototypes can produce diversified configurations to meet specific requirements. Significantly reduced masses (about 17 kg) enhance the grade‐ability when robot is in rough terrain. Performed real‐world experiments have also verified these prototypes.

The paper presents a new design approach for a mobile robot which focuses on both robot and terrain simultaneously with respect to conflicted factors. To unveil the insight relation of these factors, MOO is an effective tool to get a trade‐offs prototype.

The purpose of this paper is to reduce the torque ripple but not to decrease the average torque of synchronous reluctance machines by using one step or more than two axially laminated rotors with asymmetric flux-barrier.

A 24-slot four-pole synchronous reluctance machine with overlapping windings and asymmetric flux-barrier in the rotor is, first, described and designed by finite element (FE) method for maximizing average torque. The dimensions of asymmetric flux-barrier including the pole span angle and flux-barrier angle will be optimized to minimize the torque ripple and its influence on the average torque is also investigated by FE analysis. The impact of current angle on the average torque and torque ripple are also analysed. The step laminations together with the asymmetric flux-barrier are employed for further torque ripple reduction which can consider the both rotation directions.

The torque ripple of synchronous reluctance machine can be significantly reduced by employing asymmetric flux-barrier but the average torque is not reduced.

The purely sinusoidal currents are applied in this analysis and the effects of harmonics in the current on torque ripple are not considered in this application. The 24-slot/four-pole synchronous reluctance machine with single-layer flux-barrier has been employed in this analysis, but this work can be continued to investigate the synchronous reluctance machine with multilayer flux-barrier. This asymmetric flux-barrier can be easily applied to permanent magnet (PM)-assisted synchronous reluctance machine and the interior PM machine with flux-barrier in the rotor, since the space which is used for PM insertion is the same as the SynRM machines.

This paper has analysed the torque ripple and average torque of synchronous reluctance machines with asymmetric flux-barrier and step laminations with asymmetric flux-barrier. The torque ripple can be reduced by this flux-barrier arrangement. The difference of this technique with the other techniques such as stator/rotor skew is that the average torque can be improved.

Multilevel inverters become very popular in medium voltage applications owing to their inherent capability of reconciling stepped voltage waveform with reduced harmonic distortion and electromagnetic interference. They have several disadvantages like more number of switching devices required and devices with high voltage blocking and need additional dc sources count to engender particular voltage. So this paper aims to propose a novel tri-source symmetric cascaded multilevel inverter topology with reduced number of switching components and dc sources.

A novel multilevel inverter has been suggested in this study, offering minimal switch count in the conduction channel for the desired voltage level under symmetric and asymmetric configurations. This novel topology is optimized to prompt enormous output voltage levels by employing constant power switches count and/or dc sources of voltage. The topology claims its advantages in generating higher voltage levels with lesser number of voltage sources, gate drivers and dc voltage sources.

The consummation of the proposed arrangement is verified in Matlab/Simulink R2015b, and an experimental prototype for 7-level, 13-level, 21-level, 29-level, 25-level and 49-level operation modes is constructed to validate the simulation results.

The proposed topology operated with six new algorithms for asymmetrical configuration to propel increased number of voltage levels with reduced power components.

The purpose of this paper is to examine the calculation of magnetic field distribution in the modular amorphous transformers under short‐circuit state including the flux by the voltage supplying. The magnetically asymmetrical transformer (amorphous asymmetrical transformer – AAT) has been compared also with the symmetrical one (amorphous symmetrical transformer – AST).

3D field problems were analyzed with total ψ and reduced ϕ potentials within the finite element method (FEM). The calculated fluxes have been verified experimentally.

The field method which includes voltage excitation is helpful for flux density (B) calculation and winding reactances determination, as well. Calculations and tests yield similar flux distributions in both AST and AAT constructions. One should emphasize that AAT is better for manufacturing and repairing.

Owing to very thin (80 μm) amorphous ribbon, the solid core has been assumed for computer simulations.

Employment of a field method for calculation of the innovative three‐phase amorphous modular transformers. New construction of amorphous transformer, i.e. AAT, has been manufactured at Opole University of Technology.

With the advancement of technology, size, cost, and losses of the switched mode power supply (SMPS) have been decreasing. However, due to the high frequency switching, design of magnetic drives and isolation circuits are becoming a crucial factor in SMPS. This paper presents design criteria, procedure and implementation of AC-DC half bridge (HB) converter with lower cost, smaller size and lower voltage stress on the power switch.

The HB converter is designed in a symmetrical mode with a series coupling capacitor. Isolated power supplies are used for the converter and control circuit. Further, a transformer based isolated gate driver is used to drive both MOSFETs. The control IC works in voltage control mode to regulate voltage by controlling the duty cycle of the MOSFETs.

Control characteristics and performance of the HB converter is simulated using the MATLAB software and prototype of 170 W HB converter is built to validate the analytical results under variable load current and source voltage. The power quality and variation of load voltage at 2 A, 5 A, 7 A are reported.

This paper presents the design of a low-cost HB converter in a symmetrical mode which saves the additional cost of symmetric correction circuit normally required in asymmetrical mode design. This paper also focuses on the selection of primary and secondary side switch, series coupling capacitor, commuting diode, isolated drive and charge equalizer resistor.

Discusses the 27 papers in ISEF 1999 Proceedings on the subject of electromagnetisms. States the groups of papers cover such subjects within the discipline as: induction machines; reluctance motors; PM motors; transformers and reactors; and special problems and applications. Debates all of these in great detail and itemizes each with greater in‐depth discussion of the various technical applications and areas. Concludes that the recommendations made should be adhered to.

The purpose of this paper is to describe a computer‐aided design/manufacturing (CAD/CAM) system for fabricating facial prostheses.

The CAD/CAM system can be used for fabricating custom‐made facial prostheses with symmetrical or asymmetrical features. This system integrates non‐contact structured light scanning, reverse engineering and rapid prototyping manufacturing technology. Fringe projection based on the combination of the phase‐shift and grey‐code methods is used for data collection. A robust approach is proposed to calculate the mid‐plane of the human face without any knowledge of the centroid position or the principal axis in data processing.

Results show that the proposed method increases the fabrication accuracy and reduces the operating time. Patients were satisfied with the rehabilitation results as the custom‐made facial prostheses fitted them well.

This study improves the fabrication accuracy of facial prostheses. Three‐dimensional data of the facial surface of a patient needing a facial prosthesis were obtained with almost no harm to his body; after a series of robust processes, a precise and suitable aesthetic facial prosthesis was fabricated.

This system has bright prospects for clinical application because of its advantages over other methods in terms of speed, accuracy, safety, cost, etc.

The purpose of this paper is to analyze the phase coil connections and winding factors of flux‐switching permanent magnet (FSPM) brushless AC machines with all poles and alternate poles wound, and different combinations of stator and rotor pole numbers.

The coil‐emf vectors, which are widely used for analyzing the conventional fractional‐slot PM machines with non‐overlapping windings, are employed for FSPM machines.

Although the coil‐emf vectors have been employed to obtain coil connections in the conventional fractional‐slot PM machines, they are different in FSPM machines. It is mainly due to different polarities in the stator of FSPM machines. In addition, from the coil‐emf vectors it is able to predict whether the back‐emf waveforms are symmetrical or asymmetric.

This is the first time that coil‐emf vectors are used to determine the coil connections and winding factors in FSPM machines with different topologies and combination of stator and rotor pole numbers.

This paper aims to clarify the relationship between stator tooth shape and DC voltage fluctuation of a double salient hybrid excitation generator (DSHEG). It analyzes the asymmetrical characteristics of the magnetic circuit and inductance between each phase. The study aims to reduce voltage fluctuation by using a stator shape optimization scheme, which helps reducing inductance difference.

This paper opted for a method combined with theoretical analysis, simulation and experimental verification. The stator tooth optimization scheme is given based on theoretical asymmetrical analysis and Taguchi method. A series of two-dimensional finite element analysis simulation of different conditions are conducted. Two prototypes with different stator tooth shape are made and experiments are carried out.

The paper provides empirical insights into how the stator tooth shape influences the asymmetry of inductance and DC voltage fluctuation. Compensation adjustments to the stator tooth shape can narrow the inductance differences of each phase. It suggests that “LTL” shaped DSHEG has lower voltage ripple than “III” shaped DSHEG without sacrificing output power.

Because of the chosen research approach, the gap between magnets and stator and end effect are not considered. Errors exist between simulation and experimental results.

The paper includes implications for other “C” shaped tooth optimization. Study on phase asymmetry of the special machine can further improve quality testing and simplify control strategy.

This paper analyzes the asymmetry of DSHEG and proposes an optimized stator tooth shape to reduce DC voltage fluctuation.

The design and testing of clothing for activewear requires complex assessments of the suitability of the clothing when the body is in motion. The purpose of this paper is to investigate full body 3D scanning of active body poses in order to develop “watertight” digital models and half-scale dress forms to facilitate design, pattern making and fit analyses. Issues around creating a size set of scans in order to facilitate fit testing of activewear across a size range were also explored.

Researchers experimented to discover effective methods for 3D body capture in the cycling position and reconstruction of the body in a reliable way. In total, 25 cyclists were scanned and size representatives were selected from these participants. Methods of creating half-scale forms were developed that make optimum use of modern materials and technologies. Half-scale dress forms were created in two active positions in a range of sizes for fit testing and design. A set of half-scale and full-scale bike shorts in two styles were manufactured and fit tested on the half-scale forms compared to fit testing on the scan participants to test validity of this method of assessing fit.

Issues in capturing and reconstructing areas occluded in the scanning process, and reconstructing the interface with the bicycle seat were addressed. Active digital forms were developed across the size range, from which both digital avatars and physical mannequins were developed for pattern development and fit testing. The production and use of precisely half-scaled tools for garment testing was achieved and validated by comparing fit test results in active positions on the half-scale forms and on participants who were scanned to create these forms.

Design modifications for active positions to date are based on linear measurements alone, which do not define the 3D body adequately. Despite much research using body scanners, only limited data exist on the body in active poses, and the concept of creating half-scale forms by scanning fit models throughout the size range in active body positions is a novel concept. The progress made in resolving material and process experiments in creating the actual half-scale forms, and testing their suitability for fit testing provides a basis for further research aimed at developing similar dress forms for other activewear garments.