Length Of Poly Research Articles

Energy conversion in pole vaulting using finite element analysis

The article examines pole vaulting as a demanding track and field discipline, where athletes use a flexible pole to clear a high bar. The study explores the research challeng-es associated with this discipline, including the impact of pole material, the physical capabilities of the vaulter, and the vaulting technique on performance. The paper pre-sents a new Finite Element Analysis in ANSYS, focusing on energy conversion in the pole-vaulter interaction. Simulation results highlight the influence of pole stiffness and length for jump height, as well as the impact of synchronization between pole and pole positions on performance. Finally, the article highlights that pole vault performance is intrinsically linked to the pole vaulter's specific movement and ability to optimize interac-tion with the pole. This deeper understanding can help improve individual performance in this demanding athletics discipline.

Design of Magnetorheological Fluid Damper with Optimal Damping Force

This article focuses on designing and analyzing of an optimal Magnetorheological Fluid Damper (MRFD) having varying piston shape channeled into the piston of the MRFD. A finite element approach has been employed to investigate the impact of piston material, piston shape, MR fluid gap and pole length on the generated magnetic field density, yield stress along with damping force. Taguchi L18 orthogonal array has been exercised to obtain the optimal damping force. The Analysis of Variance (ANOVA) results investigate the contribution of the selected parameters and depict that the MR fluid gap is the most predominant factor which affects the damping force, making a contribution of 77.56%, followed by piston material which contributes 12.40%, pole length with a contribution of 8.23% and piston shape has negligible contribution of 0.07%. Taguchi predicts the optimized model for the selected parameters as A2B2C1D3 which has been validated by carrying out the analysis using ANSYS Maxwell software v. 16. The damping force of 1053 N has been obtained for the optimal MR damper model which is based on the prediction of the Taguchi results.

Tri-axial shaking table testing of lighting support systems with pulley friction dampers and integrated dummy masses

Investigating pulley wireway systems equipped with friction dampers as alternatives to traditional exposed raceway light fixtures, this study adheres to the ICC-ES AC156 standard and evaluates the impact of system mass and connector types on seismic behavior using shaking table tests. The key findings indicate that an increased system mass variably affects the fundamental frequency of the system, depending on the type of connectors. In terms of earthquake performance, direct connectors outperformed pole connectors in the original system configuration, and the addition of dummy masses significantly reduced seismic energy while stabilizing acceleration responses in pole connector systems. Moreover, the study underscores the critical importance of minimizing pole length in systems using pole connectors and adopting a lower mounting height in systems with direct connectors to improve seismic performance.

Effect of the Outer Pole Length on the Optical Properties in Gemini Lens

In order to get some of the most important optical and geometrical properties of scanning electron microscope lens, Such as focal length, lens aberration (spherical and chromatic aberration), Axial magnetic field distribution, trajectory of the electron beam, diameter of the electron probe in this work. A computer programs used to achieve the results in objective lens which called Gemini lens.by changing the outer pole length of lens to get a better optical property. The results under constant lens excitation (NI=1000 A-t) and accelerating voltage (Vr=8 KV) are (f=3.93mm, Cs=2.59mm, Cc=2.87mm) and the magnetic field distribution Bz =1.72 tesla

Mapping of 2021–2022 floods in North America from street photos with artificial intelligence

Successful flood response and evacuation require timely access to reliable flood depth information in urban areas. However, existing flood-depth-mapping tools do not provide real-time flood depth information in residential areas. In this paper, a deep convolutional neural network is used to determine flood depth through the analysis of crowdsourced images of submerged stop signs. Model performance in pole length estimation is tested on a test set, achieving a root mean squared error of 10.200 in. (1 in. = 1 inch = 2.54 cm) on pre-flood photographs and 6.156 in. on post-flood photographs and an average processing time of 0.05 s. The performance of the developed model is tested on two case studies: Hurricane Ian in the USA (2022) and the Pacific Northwest floods in the USA and Canada (2021), yielding mean absolute errors (MAEs) of 4.375 and 6.978 in., respectively. The overall MAE for both floods is achieved as 5.807 in., which is on par with those from previous studies. Additionally, detected flood depths are compared with readings reported by the nearest flood gauge on the same date. The outcome of this study demonstrates the applicability of this approach to low-cost, accurate, scalable and real-time flood risk mapping in most geographical locations, particularly in places where flood gauge reading is not feasible.

Research on cogging torque reduction method for permanent magnet synchronous motor accounting for the magnetic pole edge effect

AbstractDue to the existence of the magnetic pole edge effect, the actual cogging torque of the existing segmented step skew motor does not reach the theoretical minimum. Thus, a method for suppressing cogging torque of permanent magnet synchronous motor considering the magnetic pole edge effect is proposed. The magnetic pole edge effect is creatively converted into the amplitude and phase offset of the cogging torque generated by each pole segment. On this basis, an optimization problem is constructed in which the fundamental component of cogging torque is zero and the total harmonics is minimum. The optimal magnetic pole length and skew angle parameters of each segment are obtained by solving the optimization problem quantitatively. The results can provide theoretical guidance for motor design, which can minimize the cogging torque of step skew structures. The effectiveness of the proposed method in weakening the cogging torque of the step skew motor is demonstrated by theoretical calculation, 3D finite element analysis, and experimental results.

The Impact of Nordic Walking Pole Length on Gait Kinematic Parameters.

Nordic walking (NW) is a popular physical activity used to manage chronic diseases and maintain overall health and fitness status. This study aimed to compare NW to ordinary walking (W) with regard to pole length and to identify kinematic differences associated with different poles' length (55%, 65% and 75% of the subject's height, respectively). Twelve male volunteers (21.1 ± 0.7 years; 1.74 ± 0.05 m; 68.9 ± 6.1 kg) were tested in four conditions (W, NW55, NW65 and NW75) at three different speeds (4-5-6 km∗h-1). Each subject performed a total of twelve tests in a random order. Three-dimensional kinematics of upper and lower body were measured for both W and NW, while oxygen consumption levels (VO2) and rating of perceived exertion (RPE) were measured only for NW trials with different poles' length. NW showed a higher step length, lower elbow motion and higher trunk motion (p < 0.05) compared to W. Additionally, NW65 did not show any kinematic or RPE differences compared to NW55 and NW75. Only NW75 showed a higher elbow joint (p < 0.05) and lower pole (p < 0.05) range of motion compared to NW55 and a higher VO2 (p < 0.05) compared to NW55 and NW65 at 6 km∗h-1. In conclusion, the use of the poles affects the motion of the upper and lower body during gait. Poles with shorter or longer length do not produce particular changes in NW kinematics. However, increasing the length of the pole can be a smart variation in NW to increase exercise metabolic demand without significantly affecting the kinematics and the RPE.

Scalable flood inundation mapping using deep convolutional networks and traffic signage

Floods are one of the most prevalent and costliest natural hazards globally. The safe transit of people and goods during a flood event requires fast and reliable access to flood depth information with spatial granularity comparable to the road network. In this research, we propose to use crowdsourced photos of submerged traffic signs for street-level flood depth estimation and mapping. To this end, a deep convolutional neural network (CNN) is utilized to detect traffic signs in user-contributed photos, followed by comparing the lengths of the visible part of detected sign poles before and after the flood event. A tilt correction approach is also designed and implemented to rectify potential inaccuracy in pole length estimation caused by tilted stop signs in floodwaters. The mean absolute error (MAE) achieved for pole length estimation in pre- and post-flood photos is 1.723 and 2.846 in., respectively, leading to an MAE of 4.710 in. for flood depth estimation. The presented approach provides people and first responders with a reliable and geographically scalable solution for estimating and communicating real-time flood depth data at their locations.

Research on the torque performance for two multi-pole bilayer magnetorheological fluid couplings

This paper studies on the permanent magnets configuration on the transmission torque of the multi-pole bilayer magnetorheological (MR) coupling. Based on the electromagnetic field theory, the magnetic circuit models of traditional permanent magnet array (TPMA) and Halbach permanent magnet array (HPMA) are established, and the magnetic flux density within the MR fluid working gaps has been derived in order to evaluate the merits of the designed MR coupling. A 3D FE magnetic-fluid analysis has been necessary following the initial conceptual analysis, in order to study the influence of key parameters on the transmission torque. The results show that the transmission torque of the MR coupling with Halbach permanent magnet array is 33.45% higher than that of the ordinary permanent magnet array, with a same structure size. For the MR coupling with Halbach permanent magnet array, the unilateral magnetic focusing effect is better with the increase of the residual flux density of the secondary magnetic pole as well as the radial length of magnetic pole. And the single side magnetic focusing effect is the best when the main magnetic pole is 15°. The influence of the magnetic pole angle on the transmission torque has been further studied.

A Computerized Recognition System to Assess Breast Asymmetry after Augmentation Mammaplasty.

Breast augmentation patients are often unaware of their preexisting breast asymmetry before surgery but discover it afterward, which leads to postoperative dissatisfaction and increases the reoperation rate. However, elaboration on how patients subjectively analyze breast asymmetry and the recognition thresholds were limited. Two hundred female participants, including 100 patients 6 months postoperatively for primary augmentation mammaplasty and 100 preoperative patients, were recruited as two study groups. Self-assessments of breast asymmetry and objective measurements were taken. A computerized recognition experiment was constructed based on standardized three-dimensional models with different nipple-areola complex (NAC) and inframammary fold (IMF) asymmetry combinations. One hundred twenty-one three-dimensional models were generated and shown in random sequence. Participants responded whether they discovered breast asymmetry in each model. The recognition rate and 50% recognition thresholds of the asymmetry in NAC, IMF, lower pole length, volume, and their interrelations were calculated. Self-assessment of the postaugmentation group showed more precise distinguishing of NAC, IMF, and lower pole distance asymmetry than in the preaugmentation group. The 50% recognition thresholds of NAC and IMF level discrepancies were approximately 0.75 cm, with the IMF asymmetry identified with higher accuracy. When the NAC level discrepancy ranged from 0.0 to 1.25 cm, adjusting the IMF level discrepancy from 0.0 to 0.5 cm in the same direction lowered participants' recognition rates of breast asymmetry. Patients recognize their breast asymmetry issue more accurately after augmentation operations, despite improved parameters. In addition, adjusting the new IMF level, aligning with NAC discrepancy within 0.5 cm when treating mild NAC asymmetry, improved symmetric outcomes.

On the Annual and Semi-Annual Components of Variations in Extent of Arctic and Antarctic Sea-Ice

In this paper, the 1978–2022 series of northern (NHSI) and southern (SHSI) hemisphere sea ice extent are submitted to singular spectral analysis (SSA). The trends are quasi-linear, decreasing for NHSI (by 58,300 km2/yr) and increasing for SHSI (by 15,400 km2/yr). The amplitude of annual variation in the Antarctic is double that in the Arctic. The semi-annual components are in quadrature. The first three oscillatory components of both NHSI and SHSI, at 1, 1/2, and 1/3 yr, account for more than 95% of the signal variance. The trends are respectively 21 (Antarctic) and 4 times (Arctic) less than the amplitudes of the annual components. We next analyze variations in pole position (PM for polar motion, coordinates m1, m2) and length of day (lod). Whereas the SSA of the lod is dominated by the same first three components as sea ice, the SSA of the PM contains only the 1-yr forced annual oscillation and the Chandler 1.2-yr component. The 1-yr component of NHSI is in phase with that of the lod and in phase opposition with m1, while the reverse holds for the 1-yr component of SHSI. The semi-annual component appears in the lod and not in m1. The annual and semi-annual components of NHSI and SHSI are much larger than the trends, leading us to hypothesize that a geophysical or astronomical forcing might be preferable to the generally accepted forcing factors. The lack of modulation of the largest (SHSI) forced component does suggest an alternate mechanism. In Laplace’s theory of gravitation, the torques exerted by the Moon, Sun, and planets play the leading role as the source of forcing (modulation), leading to changes in the inclination of the Earth’s rotation axis and transferring stresses to the Earth’s envelopes. Laplace assumes that all masses on and in the Earth are set in motion by astronomical forces; more than variations in eccentricity, it is variations in the inclination of the rotation axis that lead to the large annual components of melting and re-freezing of sea-ice.

The use of ultrasonographic adrenal dimensions and the adrenal dimension-to-aorta ratio in the diagnosis of benign and malignant adrenal diseases in dogs.

Ultrasound (US) is a useful tool for detecting adrenal abnormalities. However, a definite reference range differentiating normal and diseased adrenal glands in dogs of varying body sizes is still lacking. The organ dimension-to-aorta (Ao) ratio of the dogs is correlated with their body weight (BW). Therefore, this study aimed to investigate the adrenal dimensions, including adrenal pole thickness and adrenal length, as well as the adrenal dimension-to-Ao ratio, to differentiate between dogs with normal, benign lesions such as pituitary-dependent hyperadrenocorticism (PDH) and malignant invasive adrenal tumors. The medical records and US images of 39 dogs that were either normal (normal) (n = 15) or affected by PDH (n = 15) or malignant invasive adrenal tumors (tumor) (n = 9) were retrieved in this study. All the dogs had a transabdominal US on the sagittal plane. The adrenal dimensions and luminal Ao diameter at the peak of the systolic phase were recorded. The average adrenal dimensions, including the adrenal dimension-to-Ao ratio, were compared among the groups. Most of the dogs in each group were small-breed dogs with comparable ages, BW, and Ao values. Both adrenal dimensions and the adrenal dimension-to-Ao ratio were significantly lower in the normal group than in the PDH and tumor groups. To differentiate the PDH group from the tumor group, adrenal dimensions of pole thickness and length were more appropriate than the adrenal dimension-to-Ao ratio. Adrenal dimensions and the adrenal dimension-to-Ao ratio can be used to diagnose adrenal diseases. However, in small-breed dogs, adrenal dimensions are suitable for differentiating PDH from tumor groups. Further research is required with a larger sample size and a wider range of canine body sizes.

Research on Torque Ripple Optimization of Permanent Magnet Synchronous Motor for Electric Vehicle Based on Modular Poles

AbstractAbstract in order to study the torque ripple of permanent magnet synchronous motor for electric vehicle, the method of modular poles instead of single pole is adopted to reduce the torque ripple. The modular poles consist of three kinds of permanent magnets with different remanence and are arranged in a sinusoidal distribution. The pole arc length and position of each magnetic pole are calculated according to the cutting area of sinusoidal air gap flux density wave. By changing the cutting area of sinusoidal air gap flux density wave, the optimal pole arc coefficient of each permanent magnet was determined, and the magnet pole combination with the smallest torque ripple value is obtained. The results show that the sine degree of back electromotive force is improved obviously, the cogging torque is decreased greatly, and the motor with modular poles has obvious effect on torque ripple suppression. The torque of the motor with different kinds of magnetic pole combination is more stable than that of the motor with the same kind of magnetic pole combination. In this paper, the method of using modular poles instead of single pole to reduce torque ripple is of positive significance, which provides a reference for the subsequent performance optimization of electric vehicle motor. © 2023 Institute of Electrical Engineers of Japan. Published by Wiley Periodicals LLC.

Active pole bending effect in pole support phase

ABSTRACT In pole vaulting, model analysis is one of the key methods to increase vaulting height. To date, the effects of athletes’ motions during ‘pole support phase’ have been measured and modelled to improve and set new world records. The motions were extracted based on the context of pole bending interaction and parameters to improve vaulting height were investigated. However, due to experimental, mechanical, and sensing restrictions, ranges and interactions of the parameters were poorly addressed. To investigate further, a parameter space must be globally explored. Here, we show parameter sensitivities and interactive effects between initial velocity, pole length, bending amplitude and switching time. From the simulation studies, we found that active pole bending enabled successful pole vaulting with lower initial velocity and longer poles. Vaulting height had a local maximum point at a specific initial velocity and positive bending could control conditions to deliver the local maximum height. Positive bending controls the rising-up speed of the pole and contributes to the verticalisation of the vaulting angle. Negative bending increases the vaulting speed and contributes to the robustness of the vaulting angle. Our results demonstrate how these parameters affect the vaulting performances and suggest how athletes should activate their bodies.

Non-Alcoholic Fatty Liver Disease Among Pregnant Women With Metabolic Syndrome: Should Nutritional Intervention Be a Priority? A Cross Sectional Study in Rural Sri Lanka

ObjectivesAlthough non-alcoholic fatty liver disease (NAFLD) is the hepatic manifestation of metabolic syndrome (MetS), the prevalence data of NAFLD in MetS are scarce in literature, especially in south Asian populations. Knowledge regarding NAFLD in Mets is important as both conditions can be controlled using Nutritional interventions. This study aims to compare the proportions of NAFLD among first trimester pregnant mothers with MetS and without MetS in Anuradhapura District, Sri Lanka.MethodsA community based cross-sectional comparative study was conducted among randomly selected first trimester pregnant mothers (less than 12 weeks of gestational age), in Anuradhapura district, Sri Lanka. Detailed clinical examination, biochemical investigations, and ultrasound scan(USS) to diagnose fatty liver were performed at the time of recruitment. MetS was defined according to the criteria by International Diabetes Federation, American Heart Association, and World Health Organization. NAFLD was categorized as fatty liver grades (FLG) 0, I, II and III by ultrasound criteria.ResultsOf the 634 mothers recruited, 30 (4.7%) were categorized as metabolic syndrome. The proportion of NAFLD among MetS group was 80% (n = 24/30) while it was 49.8% (n = 300/604) in none- MetS group. (Chi-sq = 10.4, p = 0.001). The proportion of FLG 0, FLG I, FLG II among MetS participants were 6(20%), 8(26.7%), 16(53.3%) respectively while they were 302(50.2%), 226(37.5%), 74(12.5%) respectively in non -MetS participants. (Chi-sq = 40, P < 0.000) None of the mothers were categorized as FLG III. The mean Gamma glutamyl transferase level and the Alanine aminotransferase levels were significantly higher (P < 0.025) in the MetS group, while no significant difference was observed in the Aspartate aminotransferase level. The mean dome to pole length of the liver among the MetS group was significantly higher (13.9 vs. 13.0 cm) in the MetS group. (t = 3.8, p = 0.001).ConclusionsThe proportion of NAFLD in pregnant mothers with MetS was significantly higher. Therefore, promising nutritional interventions are recommended to control the disease and minimize adverse pregnancy outcomes.Funding SourcesAccelerating Higher Education Expansion and Development (AHEAD) grant (Grant number: DOR STEM HEMS [6026-LK/8743-LK]), a World Bank-funded project through the University grant commission, Sri Lanka.

Rotation Angle Control Strategy for Telescopic Flexible Manipulator Based on a Combination of Fuzzy Adjustment and RBF Neural Network

The length of flexible manipulators with a telescopic arm alters during movement. The dynamic parameters of telescopic flexible manipulators exhibit significant time-varying characteristics owing to variations in length. With an increase in the manipulators’ length, the nonlinear terms caused by flexibility in the manipulators’ dynamic equations cannot be ignored. The time-varying characteristics and nonlinear terms of telescopic flexible manipulators cause fluctuations in rotation angles, which affect the operation accuracy of end-effectors. In this study, a control strategy based on a combination of fuzzy adjustment and an RBF neural network is utilized to improve the control accuracy of flexible telescopic manipulators. First, the dynamic equation of the manipulators is established using the assumed mode method and Lagrange’s principle, and the influence of nonlinear terms is analyzed. Subsequently, a combined control strategy is proposed to suppress the fluctuation of the rotation angle in telescopic flexible manipulators. The variation ranges of the feedforward PD controller parameters are determined by the pole placement strategy and length of the manipulators. Fuzzy rules are utilized to adjust the controller parameters in real-time. The RBF neural network is utilized to identify and compensate the uncertain part of the dynamic model of the flexible manipulators. The uncertain part comprises time-varying parameters and nonlinear terms. Finally, numerical simulations and prototype experiments prove the effectiveness of the combined control strategy. The results prove that the proposed control strategy has a smaller standard deviation of errors. Therefore, the combined control strategy is more suitable for telescopic flexible manipulators, which can effectively improve the control accuracy of rotation angles.

Self-Motion of Water Droplets along a Spacing Gradient of Micropillar Arrays on Copper.

Self-driven droplet transport along an open gradient surface is increasingly becoming popular for various microfluidics applications. In this work, a gradient copper oxide layer is formed on a copper sheet (as a bipolar electrode, BPE) in a KOH solution by bipolar electrochemistry. The deposits at different positions present a rich variety of colors, compositions, and microstructures along the longitudinal axis of the BPE. More than half the length of the anodic pole is covered by a Cu(OH)2/CuO composite layer of several micrometers thick, which is composed of dense micropillars with a decreasing spacing gradient to the anodic direction. The micropillar arrays are superhydrophilic, and after modified with 1-dodecanethiol, the tops of the dense micropillars constitute a hydrophobic and microscopically discontinuous surface with a wettability gradient. On such a gradient surface water droplets can move spontaneously to more hydrophilic direction at a velocity of about 16 mm s-1. The superhydrophobicity of the modified micropillar arrays is discussed through a comparison with the wax tubules on a lotus leaf. Theoretical analysis of the driving force reveals that the concave surface effect of water at the spacings between the micropillars is the critical factor for driving the rolling motion of the droplets along the gradient micropillar arrays.

A mathematical model of cavitation behaviour in a single-ended magnetorheological damper: experimental validation

This paper proposes a mathematical model of the cavitation behavior to occur in a single-ended magnetorheological (MR) damper (MRD), and the effectiveness of the model is validated through the comparison with experimental results. Several causes of the cavitation behavior of MRD are discussed with different conditions of the initial pressure of the gas chamber and the piston stroke speed. The model to capture the cavitation behavior is then formulated considering differential equations for gas volume, internal pressure, ideal gas law, and bulk modulus of MR fluid. To calculate the flow rate, which is difficult to solve from the differential equations, the model is approximated as a nondimensional equation the parameters of the yield stress and pole length. Subsequently, the field-dependent damping force of MRD is computed using the gaseous cavitation model and nondimensional equation. To validate the proposed cavitation model, a single-ended MRD is designed, manufactured, and tested. It is observed that the damping force characteristics under cavitation are revealed to be much different from those under regular operation without cavitation. More specifically, it is hard to calculate the dissipation energy and hysteretic damping due to highly nonlinear characteristics with respect to the stroke and velocity. However, the proposed model can fairly capture the cavitation behavior showing an excellent agreement between simulation and experiment. In this work, to confirm the internal influence of MRD by cavitation, which is difficult to confirm experimentally, the changes of the pressure distribution and the gas-to-liquid volume ratio are analyzed through the simulation of the nondimensional equation. In addition, the bubbles representing the cavitation behavior are visually observed from the lower chamber of MRD.

Anthropometric Breast Measurements: Analysis of the Average Breast in the Mexican Female Population

Introduction: The elements and perception of beauty vary between populations around the world. To obtain better results, surgical techniques should be planned based on anthropometric characteristics of the race, location, and body mass index (BMI). Objectives: To determine which are the standard measurements and anatomical proportions of the breast in a healthy Mexican women population. Materials and Methods: Female Mexican volunteers between 20 and 60 years of age, without any history of breast illness or breast surgery were studied. Demographic information and standard breast anthropometric measurements were collected manually by one of the authors. For the statistical analysis a Student-T test was performed, and the Pearson correlation coefficient was obtained using the latest version of SPSS software. Results: 78 volunteers were included in the analysis. Mean height, weight and BMI were 1.6 m, 68.9 Kg, and 26.6 Kg/m2 respectively. The mean anthropometric values found were: Supra Sternal notch to nipple distance (SSN:N) 22 cm, Breast volume (BV) 372.6 cm3, Upper breast pole length (UBPL) 11 cm, Lower Breast Pole length (LBPL) 7.7 cm, Midline to Nipple distance (ML:N) 10.2 cm, Transverse diameter of the Nipple areola complex (NAC-T) 4.1 cm, Height of the Nipple Areola Complex (NAC-H) 4.1 cm, Base of the breast (BB) 13.4 cm, Upper Pole to Lower Pole Ratio (UPP:LPP) 58.9:41.1. A statistically significant difference between Right and left breast was not found. The UPP/ LPP ratio in our population is far different from what is considered internationally aesthetic (45:55). A positive correlation was found between weight/ BMI and SSN:N, BV, BB, ML:N and LBPL. Also between age and SSN:N, LBPL, BV and BB. Conclusion: This study sets the Anthropometric grounds in Mexican population for an objective individual patient analysis and comparison with the female population of this and other nations.

Magnetic field and electromagnetic performance analysis of permanent magnet machines with segmented Halbach array

PurposeThis study aims to accurately calculate the magnetic field distribution, which is a prerequisite for pre-design and optimization of electromagnetic performance. Accurate calculation of magnetic field distribution is a prerequisite for pre-design and optimization.Design/methodology/approachThis paper proposes an analytical model of permanent magnet machines with segmented Halbach array (SHA-PMMs) to predict the magnetic field distribution and electromagnetic performance. The field problem is divided into four subdomains, i.e. permanent magnet, air-gap, stator slot and slot opening. The Poisson’s equation or Laplace’s equation of magnetic vector potential for each subdomain is solved. The field’s solution is obtained by applying the boundary conditions. The electromagnetic performances, such as magnetic flux density, unbalanced magnetic force, cogging torque and electromagnetic torque, are analytically predicted. Then, the influence of design parameters on the torque is explored by using the analytical model.FindingsThe finite element analysis and prototype experiments verify the analytical model’s accuracy. Adjusting the design parameters, e.g. segments per pole and air-gap length, can effectively increase the electromagnetic torque and simultaneously reduce the torque ripple.Originality/valueThe main contribution of this paper is to develop an accurate magnetic field analytical model of the SHA-PMMs. It can precisely describe complex topology, e.g. arbitrary segmented Halbach array and semi-closed slots, etc., and can quickly predict the magnetic field distribution and electromagnetic performance simultaneously.