Rim Design Research Articles

The effect of a novel square-profile hand rim on propulsion technique of wheelchair tennis players

The purpose of this study was to investigate the effect of a square-profile hand rim (SPR) on propulsion technique of wheelchair tennis players. Eight experienced wheelchair tennis players performed two sets of three submaximal exercise tests and six sprint tests on a wheelchair ergometer, once with a regular rim (RR) and once with a SPR. Torque and velocity were measured continuously and power output and timing variables were calculated. No significant differences were found in propulsion technique between the RR and SPR during the submaximal tests. When sprinting with the racket, the SPR showed a significantly lower overall speed (9.1 vs. 9.8 m s−1), maximal speed (10.5 vs. 11.4 m s−1), and maximal acceleration (18.6 vs. 10.9 m s−2). The SPR does not seem to improve the propulsion technique when propelling a wheelchair with a tennis racket in the hand. However, the results gave input for new hand rim designs for wheelchair tennis.

Experimental study of the effect of restraining rim design on the extreme behavior of pendulum sliding bearings

SummaryWhile the performance of sliding isolators has been extensively validated under typical levels of ground motion, there have been very few experimental studies on the extreme behavior of sliding isolation bearings when the displacement limit is reached. However, to appropriately design isolated systems, from selecting the displacement capacity of the bearing to sizing the superstructure members, the behavior of the bearing as it reaches, and in some cases exceeds, the displacement limit should be well understood. A series of shake table tests to investigate the extreme behavior of double pendulum sliding bearings under strong ground motions were conducted at McMaster University. One major difference in sliding bearings around the world is how the motion of the bearing is restrained at the bearing's displacement capacity. Scaled bearings with four different types of restraining rim designs were included, representing typical sliding restraining rims found in Europe, Japan, and the United States. Experimental observation shows that the restraining rim has a significant influence on the extreme behavior of sliding isolation bearing. Key response parameters such as impact force and uplift are evaluated and compared between the different sliding bearing designs. While the bearing with no rim bearing imparts the lowest forces to the superstructure, it loses its functionality at a lower amplitude input than all the other rim types. For the other rim designs, the impact forces are significantly higher but they remained operational although damaged.

Investigation of Stress and Displacement Distribution in Advanced Steel Rims

Over the years, lightweight rim design has attracted attention. Light alloy materials have been used as rim material for various type of vehicle. The main objective of the study is obtaining a lightweight rim design by using advanced steel. The wheels are crucial parts of vehicle for human safety because of their function. Therefore, verification of the rim design is important in automotive engineering. In this study, finite element analysis method is used to verify the advanced steel design. In addition, the finite element modelling technique is also used to obtain a time- efficient result. The stress and deformation distribution of advanced steel rim design are compared with steel and aluminum alloy rim design. The influence of inflation pressure, vehicle weight and velocity are taken in consideration. The analysis results are presented as von-Mises stress and deformation distribution figures.

Study on the design method of equal strength rim based on stress and fatigue analysis using finite element method

Wheels are important safety components in the vehicle driving system. Automobile lightweight is the direction of the modern automobile development. In this article, steel wheel lightweight was studied. The equal strength design of rim was used to reduce the weight of the wheel. Stress analysis of the wheel was studied using UG/Nastran. A professional software WheelStrength was used to predict the radial and cornering fatigue lives of the wheel. Sheet stamping process was set up to analyze the interference fit between the disk and the rim. The assembly was simulated by axisymmetric finite element method. After calculation and analysis, the stress distributions and fatigue lives for rim under different load cases have been found. The thicknesses of wheel rim bead and the interface between rim and disk cannot be reduced. Stress and fatigue simulation results were compared using different thicknesses of the optimized region. It was found that the best thickness of the optimized region was 1.5 mm. Spinning was used to form the flared preform. The thickness of the rim after spinning and rolling forming agreed well with the simulation. The results of fatigue tests indicated that the lightweight wheel met the design requirement. The weight of the rim was reduced by about 14%.

Motorcycle Tire Modeling for the Study of Tire–Rim Interaction

For the lightweight design of the wheel rim of motorcycles, the knowledge of the way in which contact forces are transmitted by the tire is of crucial importance. In this paper, an analytical model of the tire is developed and explicit formulae giving the distribution of the radial and axial forces acting on the wheel rim for a given vertical load are derived. The analytical model is validated by means of a finite element method (FEM) model and experimental tests. The proposed analytical model is able to predict the radial deflection of both a front and a rear tire for a racing motorbike with very good accuracy over a wide range of inflating pressures and vertical loads. The force distributions are in very good agreement with the results of the FEM model. Experimental tests show that the force distribution at the interface between the tire and rim can be used to predict the stress distribution in the rim with a good accuracy.

Design and Performance Analysis of Double Stator Axial Flux PM Generator for Rim Driven Marine Current Turbines

This paper presents the design and performance analysis of double stator axial flux permanent magnet generators for rim-driven marine current turbines (MCT). In submarine applications, drive train reliability is a key feature for reducing maintenance requirements. Rim-driven, direct-drive, multistator generators can therefore be an interesting solution to improve reliability. In this context, the work presented here focuses on the design of a double-stator, axial flux, permanent magnet (PM) generator as a rim-driven, direct-drive, multistator generator. The models, specifications and an optimization procedure that facilitate the preliminary design of these kinds of generators for rim-driven marine turbines are presented. Validation with finite element computations and a performance analysis for a particular design of rim driven generators are conducted. The results obtained highlight some designs issues associated with PM generators for rim driven marine turbines. To assess the effectiveness of the double stator axial flux PM generator, a comparison with a surface mounted radial flux PM generator design for rim marine turbines is carried out. The comparison shows that the double stator axial flux generator has a better cooling characteristic and a reduced active parts cost and mass than the radial flux PM generator.

2106 ロードバイク用アルミ製リムの設計に関する基礎的検討(D&Sコンテストショートプレゼンテーション,DC0 D&Sコンテスト口頭発表)

2106 ロードバイク用アルミ製リムの設計に関する基礎的検討(D&Sコンテストショートプレゼンテーション,DC0 D&Sコンテスト口頭発表)

FSC赛车轮辋轻量化设计

根据FSC赛车设计规则要求，将轮辋作为分析研究的对象，运用三维造型软件UG完成车轮三维几何建模，使用分析软件ANSYS建立冲击块与铝合金轮辋的非线性有限元力学模型，分析了冲击块与轮辋的冲击参数。最后根据分析结果对轮辋进行轻量化设计，该研究为赛车轮辋的设计提供了理论支持。 According to FSC racing design rules, the wheel rim is used to be the object in this paper. The three-dimensional modeling software UG has been used to complete 3D geometric modeling of wheels. The analysis software ANSYS has been used to establish nonlinear finite element model of the impact block and aluminum rims. The impact parameters of the block and the rim are analyzed. Finally, according to analyzed results, the lightweight design for rim has been carried out. The study can provide theoretical support for racing rim design.

Design Decision Automation Support through Knowledge Template CAD Model

ABSTRACTToday industries and companies are trying hard to reduce lead times and costs for new products, in order to satisfy customer requirements and maintain design quality. This paper presents the procedure and methodology to develop Knowledge template CAD model. This template is an “intelligent” CAD model which replaces the design library usually in the form of database. In this work the Knowledge Template (KT) is designed using Knowledge Base Engineering (KBE) elements such as design constraints, design rules, expressions, Graphical User Interface (GUI) and programs. The proposed KT gets automatically configured to fit for specific context (best design solution) according to the user input. The proposed methodology provide decision support system and tool to help the customer to choose promising design alternatives from KT according to their needs and desires. Design of wheel rim is presented, as an example, to validate the proposed concept of KT. With the proposed KT, it is possible to achieve direct...

Application of Shape Optimization Method on Steel Wheel Rim

Nowadays, weight reduction is great opportunity for automotive components design due to meet the structural strength without reducing the components safety. A classical try-and-error approach to design the automotive components in industries is inadequate which mean new methods are needed to enhance the design process. An improvement of the component can be achieved by adopting suitable optimization techniques at the early design stage. In this paper, the problem of automotive component design; steel wheel rim design in a view of weight reduction was tackled by means of shape optimization method. Design methodology was proposed to the original design of selected wheel rim and was continued optimized them by various reduction targets. The optimized design together with the datum has been analyzed and the results were compared and discussed. Shape optimization with 15% of reduction target at steel wheel rim was the best optimal design and it was met the design criteria and safety factor. By applying shape optimization, weight of steel wheel also has been reduced by using proper reduction target. The methodology has been proven to be successful in finding innovative and efficient layouts for automotive components design.

Investigation of Wheel Aerodynamic Resistance of Passenger Cars

There are a number of numerical and experimental studies of the aerodynamic performance of wheels that have been published. They show that wheels and wheel-housing flows are responsible for a substantial part of the total aerodynamic drag on passenger vehicles. Previous investigations have also shown that aerodynamic resistance moment acting on rotating wheels, sometimes referred to as ventilation resistance or ventilation torque is a significant contributor to the total aerodynamic resistance of the vehicle; therefore it should not be neglected when designing the wheel-housing area. This work presents a numerical study of the wheel ventilation resistance moment and factors that affect it, using computational fluid dynamics (CFD). It is demonstrated how pressure and shear forces acting on different rotating parts of the wheel affect the ventilation torque. It is also shown how a simple change of rim design can lead to a significant decrease in power consumption of the vehicle. A way of introducing ventilation torque into the driving resistance equation is discussed. The results show that it is possible to assess ventilation resistance moment using CFD. It is demonstrated that brake discs have almost negligible ventilation torque, while the contribution of rims and tyres may vary depending on the rim design used and the velocity of the vehicle. It is also shown that for the designs investigated the equivalent ventilation force has a second order dependency on the vehicle velocity which allows an introduction of a ventilation resistance coefficient CD(vent) that is independent of velocity.

Ancestral Caddo Ceramics in East Texas

The most distinctive material culture item of the ancestral Caddo groups that lived in East Texas from ca. A.D. 900 to the 1830s were the ceramics they manufactured primarily for cooking, storage, and serving needs. The decorative styles and vessels forms of the ceramics found at sites in the region hint at the variety, temporal span, and geographic extent of a number of ancestral Caddo groups that lived in this area. The diversity in decoration and shape of Caddo ceramics is considerable, both in the utility ware jars and bowls, as well as in the fine ware bottles, carinated bowls, and compound vessels. Ceramics are quite common in domestic contexts on habitation sites across the region, and whole vessels also occur as grave goods in mortuary contexts. The Caddo manufactured ceramics in a wide variety of vessel shapes, and with an abundance of well-crafted and executed body and rim designs paired with smoothed, burnished, or polished surface treatments. From the archaeological contexts in which Caddo ceramics have been found, as well as through inferences about their manufacture and use, it is evident that ceramics were important to the ancestral Caddo in: the cooking and serving of foods and beverages, for the storage of foodstuffs, as personal possessions, as incense burners, as beautiful works of art and craftsmanship (i.e., some vessels were clearly made to never be used in domestic contexts), and as social identifiers. In the case of the later, certain shared and distinctive stylistic motifs and decorative patterns on ceramic vessels marked closely related communities and constituent groups.

Investigation of the Influence of Tyre Geometry on the Aerodynamics of Passenger Cars

It is well known that wheels are responsible for a significant amount of the total aerodynamic drag of passenger vehicles. Tyres, and mostly rims, have been the subject of research in the automotive industry for the past years, but their effect and interaction with each other and with the car exterior is still not completely understood. This paper focuses on the use of CFD to study the effects of tyre geometry (tyre profile and tyre tread) on road vehicle aerodynamics. Whenever possible, results of the numerical computations are compared with experiments. More than sixty configurations were simulated. These simulations combined different tyre profiles, treads, rim designs and spoke orientation on two car types: a sedan and a sports wagon. Two tyre geometries were obtained directly from the tyre manufacturer, while a third geometry was obtained from our database and represents a generic tyre which covers different profiles of a given tyre size. All geometries were deformed based on measured wind tunnel data under a defined load and rotating conditions of 100 kph. Results have shown that the main grooves consistently lead to a decrease of both drag and lift. The edge pattern however, did not show a clear trend for drag and lift with respect to the different configurations studied, although its influence was always more noticeable on the sports wagon. The larger profile of the generic tyre resulted in higher drag and lift values with relation to the tyres obtained from the manufacturer. For a given rim, a drag difference was observed between two tyre geometries with same profile but different tyre tread. These findings lead to the conclusion that tyre profile, as well as tyre pattern, are important to consider. These results were confirmed by wind tunnel tests. In conclusion, the work of aerodynamic optimization of rims cannot be separated from the tyre itself.

Investigation of Wheel Ventilation-Drag using a Modular Wheel Design Concept

Passenger car fuel consumption is a constant concern for automotive companies and the contribution to fuel consumption from aerodynamics is well known. Several studies have been published on the aerodynamics of wheels. One area of wheel aerodynamics discussed in some of these earlier works is the so-called ventilation resistance. This study investigates ventilation resistance on a number of 17 inch rims, in the Volvo Cars Aerodynamic Wind Tunnel. The ventilation resistance was measured using a custom–built suspension with a tractive force measurement system installed in the Wheel Drive Units (WDUs). The study aims at identifying wheel design factors that have significant effect on the ventilation resistance for the investigated wheel size. The results show that it was possible to measure similar power requirements to rotate the wheels as was found in previous works. The magnitude of the measured ventilation resistance confirms the conclusion that this effect should be taken into account when designing a wheel. It was found that some of the rim design factors have greater influences on the ventilation resistance than others. It was also shown that one of the investigated rims had lower ventilation resistance than measured for the fully-covered wheel configuration.

Design optimization and fabrication of a hybrid composite flywheel rotor

This paper discusses three different rim design cases of a hybrid composite flywheel rotor using strength ratio optimization. The rotor is composed of four hybrid composite rims. These rims are made from carbon–glass/epoxy with varying volume fractions of hoop wound reinforcements. Optimization is performed to reduce the maximum strength ratio during two rotor states: stationary and the maximum allowable rotational speed. The input specifications for optimization are: maximum useable energy (35kWh), rotational speed (15,000rpm), height, and inner radius. In the first case, the rims are wound simultaneously by continuous winding. However, in the second case, the rims are wound separately, and interferences are incorporated for their assembly by press fit. In the third case, a hybrid version of the first two cases is used, whereby two pairs of rims are wound at the same time, and in a secondary operation, the first pair is press fitted to the second pair. Each case has different fabrication costs and different strength ratios. The third case rotor has been successfully manufactured by filament winding with in situ curing, followed by press fit assembly of machined rims.

Design of Hybrid Composite Multilayer Rim of High Speed Energy Storage Flywheels

The large flywheel energy storage system requires very high radial tensile strength of the flywheel rim, for the sake of the ultimate strength requirement, multilayer flywheel rim structure of carbon fiber/glass fiber hybrid composite is employed in the paper. Both stress calculation and FEM analysis show that rational densign of the layer thickness and the hybrid ratio of carbon fiber to glass fiber can reduce radial strength requirement of rim material, especially for large flywheel energy storage system.

微框架效应磁悬浮飞轮转子轮缘优化设计

A 5 DOF magnetically suspended flywheel with vernier gimballing capacity which is composed of a conoid reluctive bearing and a Lorentz magnetic bear was investigated and its rotor rim was designed optimally.Based on the structure of the rotor and the goal to minimize the mass of the rim,the mass,inertial moment and resonance frequency of the rim were analyzed theoretically to confirm the optimal variables.Consequently,an optimal design was achieved through iSIGHT and ANSYS,and by taking the number of spokes into account,the variables were optimized by the sequential quadratic programming algorithm in the restrain cases of the resonance frequency,inertial moment,maximum equivalent stress,and the ratio of polar inertia moment to equinoctial inertial moment.Those results of optimization indicate that the mass of the rim is decreased from 2.226 kg to 2.036 kg(namely reduced by 8.54%) when the number of spokes is 3 and other design variables are optimal.The proposed optimal design method can improve the rationality and efficiency of rotor design,and will be an important part in the optimal design of flywheel systems.

A Squeaky Reputation: The Problem May Be Design-dependent

Squeaking is reportedly a complication in patients having ceramic-on-ceramic total hip implants. The etiology remains unknown and multifactorial with recent studies suggesting a relationship between the audible squeak and implant design. When we evaluated our ceramic-on-ceramic cohort, we noticed squeaking primarily in patients receiving an acetabular system designed with an elevated titanium rim. We therefore (1) determined the incidence of squeaking among four different ceramic-on-ceramic bearing surfaces used for THA at our institution; (2) evaluated the association between different acetabular designs and the incidence of squeaking; and (3) assessed other potential variables associated with squeaking. We retrospectively reviewed 1507 patients having a ceramic-on-ceramic THA between 2002 and 2009; we separately analyzed those receiving an acetabular system with and without an elevated titanium rim. Data were collected through phone-administered questionnaires and retrospective reviews of patient charts for intraoperative findings, followup reports, demographic information, and radiographic findings. Squeaking occurred in 92 of the 1507 patients (6%). All 92 patients with squeaking received an elevated rim design (1291 patients) or an incidence of 7% with that design. We found no association between squeaking and any other examined factors. Our findings complement the theory from in vitro studies suggesting that neck impingement on the elevated titanium rim is the probable cause of the increased frequency of squeaking with this design.

Influence of Acetabular Cup Rim Design on the Contact Stress During Edge Loading in Ceramic-on-Ceramic Hip Prostheses

The purpose of the study was to investigate the contact stresses in 3 different acetabular cup rim designs (new, worn, chamfer) during edge loading, after microseparation of ceramic on ceramic hip prostheses. A 3-dimensional finite element analysis was conducted for a 28-mm diameter alumina ceramic bearing with a radial clearance of 40 μm using a normal load of 2500 N under edge loading. At a separation distance of 250 μm, the maximum tensile stress in the “new” design was of similar magnitude to the flexural strength of the alumina material that supports the localized breakdown (stripe wear) of the acetabular cup surface observed clinically. Introducing a 2.5-mm radius chamfer should reduce the maximum tensile stress in the region of 60%.

Long-term results of the ABG-1 hydroxyapatite coated total hip arthroplasty: Analysis of 111 cases with a minimum follow-up of 10 years

Medium-term studies of ABG-1 cementless total hip arthroplasty have shown favorable functional results with excellent femoral component fixation but an abnormally high rate of periacetabular component osteolysis, which may require early revision. The periacetabular osteolysis rate increases with time with the ABG-1 implant, leading to a high revision rate. The objective of this study was to test this hypothesis with a minimum follow-up of 10 years and evaluate the progression of periacetabular osteolysis and its consequences on implant fixation. A continuous series of 111 ABG-1 cementless prostheses implanted by a single operator with a theoretical minimum follow-up of 10 years. Seventy-five implants were analyzed with a mean follow-up of 13 years. All the prostheses had been implanted via a posterolateral approach and consisted of a 28 mm cup matching a head in zirconia and an antidislocation rim design high-density polyethylene insert. Twelve cups were revised because of progressive retroacetabular osteolysis. The revisions were performed systematically although there was no pain or gross cup loosening. The revisions included resection of the granuloma, cavity filling with morselized bone grafts, and implantation of new uncemented ABG-2 cups in eight cases or cemented cups associated with a support ring in the four other cases. Thirty-two (48.5%) of the cups still in place at the end of the follow-up evaluation presented moderate and asymptomatic radiographic osteolysis, inciting close subsequent observation. No predictive factor of osteolysis onset was identified (age, body mass index, polyethylene wear, or cup orientation). None of the femoral stems was changed because of osteolysis: the only two femoral revisions resulted from periprosthetic fracture and one case of bipolar loosening. The femoral osteolysis images were small and all limited to zones 7a (18.8% of cases), 1a, and 1b (65.2% of cases). The overall survival rate of the series at 13 years of follow-up was 80.5%; the cup survival rate was 83.2%; the femoral implant, 94.3%; and failure of the femoral stem secondary to aseptic loosening was only 1.3%. This long-term study confirms the high frequency of retroacetabular osteolysis of ABG-1 prostheses surpassing the osteolysis rate of other uncemented cups with a polyethylene insert. The absence of predictive criteria of osteolysis occurrence and the lack of symptoms warrants periodic follow-up of patients with ABG-1 cups and, if necessary, early repair of bone stock loss with grafts combined with acetabular cup revision. This procedure remains simple as long as performed before the onset of massive bone destruction, confirming the proposed revisions in this series were judicious. This study also confirms the excellent long-term fixation of the ABG-1 femoral stems derived from the osteointegration and proximal seal around the hydroxyapatite coating.