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Actively controlling the camber angle to improve energy efficiency has recently gained interest due to the importance of reducing energy consumption and the driveline electrification trend that makes cost-efficient implementation of actuators possible. To analyse how much energy that can be saved with camber control, the effect of changing the camber angles on the forces and moments of the tyre under different driving conditions should be considered. In this paper, Magic Formula tyre models for combined slip and camber are used for simulation of energy analysis. The components of power loss during cornering are formulated and used to explain the influence that camber angles have on the power loss. For the studied driving paths and the assumed driver model, the simulation results show that active camber control can have considerable influence on power loss during cornering. Different combinations of camber angles are simulated, and a camber control algorithm is proposed and verified in simulation. The results show that the camber controller has very promising application prospects for energy-efficient cornering.

O subsistema suspensão é importante na dinâmica veicular, porque proporcionaestabilidade, dirigibilidade, garantia de aderência pneu-solo, assim como conforto aospassageiros. A geometria do sistema de suspensão, garantida pelo câmber, caster econvergência, é fundamental em seu desempenho, pois exerce influência na integridade dosdemais subsistemas do veículo. O objetivo do presente trabalho é mostrar a integração deambientes CAD/CAE na avaliação dos parâmetros de geometria de um ¼ de suspensãoDuplo “A”. As coordenadas dos principais pontos da suspensão e a geometria das massas deseus componentes são obtidas do modelo CAD. A modelagem CAE se dá em ambientemulticorpos, onde se constrói o modelo com points e polylines (Construction Geometry). Ointuito da estratégia de modelagem é tornar o modelo da suspensão menos sobrecarregado;permitir que juntas e conectores flexíveis sejam mais facilmente inseridos, sem que se tenhasobreposição de markers das juntas/buchas com aqueles de corpos rígidos (links, por exemplo), além de evitar a operação de “hide”, caso se queira utilizar a máscara CAD nomecanismo. Essa fase do trabalho, constitui a fase inicial de avaliação de ¼ de suspensão,que será, posteriormente, utilizada para o estudo de vibrações em corpo inteiro.

The Utah Transportation Center (UTC) as well as the Mountain Plains Consortium, sponsored a study to investigate the long-term performance of a deck bulb tee girder bridge. The bridge in question is located in Nibley, Utah and was erected in early 2016. Temperature and prestress losses were analyzed from embedded instrumentation placed within two of the bridge girders before casting. These two girders contained a total of 50 thermocouples and 16 vibrating wire strain gauges. These instruments were placed at the mid-span and end of an exterior girder and the mid-span, quarter-span, and end of a center girder in order to effectively monitor the bridge response in one quarter of the bridge superstructure. The monitoring performed with the thermocouples included the temperature of the girders during curing, weekly maximum and minimum temperatures compared to methods for predicting the average bridge temperature, maximum and minimum thermal gradients at each of the five selected cross sections compared to Code thermal gradients, and thermal camber by measured temperature compared to models to predict thermal gradients. The 16 strain gauges measured prestress losses at four girder cross-sections, which were compared to two predictive methods provided by AASHTO as well as a method by PCI. An additional comparison of the equations provided by AASHTO and a newly available equation used for determining the modulus of elasticity of concretes with a compressive strength of 6,000 ��� 12,000 psi was performed. Additional exterior instrumentation were provided by Bridge Diagnostics Inc. (BDI) in order to monitor short-term changes within the bridge. A total of 8 strain gauges were attached to the exterior of the girders with 6 attached at the bottom face of 6 girders and 2 attached at the centroid of 2 girders. These sensors as well as the software and wireless data acquisition provided a method to measure the magnitude and frequency of the ranges of strain experienced by the Nibley Bridge.

The roll deflection during hot rolling can result in uneven thickness distribution across the width of a plate (crown). A conventional rolling mill is equipped with bending systems that can control this convex shape of the plate. However, the determination of the proper bending load is very complicated as the plate crown is influenced by the rolling conditions. In this paper, a thermo-mechanical Finite Element Model on LS-DYNA&trade, software was utilized to predict crown evolution based on the rolling conditions in order to determine the setting values for achieving the target crown. The simulation results were compared and verified with actual industrial data for rolling force, plate temperature and plate crown. This approach is essential for pass schedule design and process parameter optimization in order to achieve the desired product quality.

Numerical modeling of the prestressing element that generates prestressed effect in beams has always been considered a big challenge. This research compares two methods of modeling; In the first method we used initial stresses predefined stress and in the second method we used the temperature strain. Concrete damage plasticity model (CDP) was used to model the non-linear behavior of concrete material and an elasto-plastic behavior was applied to ordinary and prestressed reinforcement. Truss elements were used to model ordinary and prestressed reinforcement embedded inside the concrete. As a result, Initial Temperature load method showed less error in bottom and top stresses and cambering of beam in comparison with the basic concept method, than predefined method.

Among many trade-offs in the automotive technologies, fuel economy and the steering stability are one of the typical case. In this report, we verified the effects of changing camber angles in response to driving conditions, in attempts to improve both the fuel economy and vehicle stability during comparing maneuver.

Optimizing mobility performance in wheelchair court sports (basketball, rugby and tennis) is dependent on a combination of factors associated with the user, the wheelchair and the interfacing between the two. Substantial research has been attributed to the wheelchair athlete yet very little has focused on the role of the wheelchair and the wheelchair-user combination. This article aims to review relevant scientific literature that has investigated the effects of wheelchair configuration on aspects of mobility performance from an ergonomics perspective. Optimizing performance from an ergonomics perspective requires a multidisciplinary approach. This has resulted in laboratory-based investigations incorporating a combination of physiological and biomechanical analyses to assess the efficiency, health/safety and comfort of various wheelchair configurations. To a lesser extent, field-based testing has also been incorporated to determine the effects of wheelchair configuration on aspects of mobility performance specific to the wheelchair court sports. The available literature has demonstrated that areas of seat positioning, rear wheel camber, wheel size and hand-rim configurations can all influence the ergonomics of wheelchair performance. Certain configurations have been found to elevate the physiological demand of wheelchair propulsion, others have been associated with an increased risk of injury and some have demonstrated favourable performance on court. A consideration of all these factors is required to identify optimal wheelchair configurations. Unfortunately, a wide variety of different methodologies have immerged between studies, many of which are accompanied by limitations, thus making the identification of optimal configurations problematic. When investigating an area of wheelchair configuration, many studies have failed to adequately standardize other areas, which has prevented reliable cause and effect. relationships being established. In addition, a large number of studies have explored the effects of wheelchair configuration in either able-bodied populations or in daily life or racing wheelchairs. As such, the findings are not specific and transferable to athletes competing in the wheelchair court sports. This review presents evidence about the effects of wheelchair configuration on aspects of mobility performance specific to the wheelchair court sports to better inform athletes, coaches and manufacturers about the consequences of their selections. It also provides researchers with guidance on the design of future investigations into areas of wheelchair configuration, which are essential.

Optimizing mobility performance in wheelchair court sports (basketball, rugby and tennis) is dependent on a combination of factors associated with the user, the wheelchair and the interfacing between the two. Substantial research has been attributed to the wheelchair athlete yet very little has focused on the role of the wheelchair and the wheelchair-user combination. This article aims to review relevant scientific literature that has investigated the effects of wheelchair configuration on aspects of mobility performance from an ergonomics perspective. Optimizing performance from an ergonomics perspective requires a multidisciplinary approach. This has resulted in laboratory-based investigations incorporating a combination of physiological and biomechanical analyses to assess the efficiency, health/safety and comfort of various wheelchair configurations. To a lesser extent, field-based testing has also been incorporated to determine the effects of wheelchair configuration on aspects of mobility performance specific to the wheelchair court sports. The available literature has demonstrated that areas of seat positioning, rear wheel camber, wheel size and hand-rim configurations can all influence the ergonomics of wheelchair performance. Certain configurations have been found to elevate the physiological demand of wheelchair propulsion, others have been associated with an increased risk of injury and some have demonstrated favourable performance on court. A consideration of all these factors is required to identify optimal wheelchair configurations. Unfortunately, a wide variety of different methodologies have immerged between studies, many of which are accompanied by limitations, thus making the identification of optimal configurations problematic. When investigating an area of wheelchair configuration, many studies have failed to adequately standardize other areas, which has prevented reliable cause and effect. relationships being established. In addition, a large number of studies have explored the effects of wheelchair configuration in either able-bodied populations or in daily life or racing wheelchairs. As such, the findings are not specific and transferable to athletes competing in the wheelchair court sports. This review presents evidence about the effects of wheelchair configuration on aspects of mobility performance specific to the wheelchair court sports to better inform athletes, coaches and manufacturers about the consequences of their selections. It also provides researchers with guidance on the design of future investigations into areas of wheelchair configuration, which are essential.

In the article results of the analysis of the basic parameters of suspension of domestic and foreign teams "Formula Student" are presented. Based on the analysis we made the choice of suspension parameters like wheelbase, halftrack, alignment and size of the wheels for "Formula Student" racing car.

The process of calculating exterior camera parameters is described according to the theory of machine vision. To calculate the toe and camber angles, an algorithm for obtaining the direction vector of wheel axle was developed. Algorithm can be used as well, when the lift plane is not horizontal.

Mahasarakham International Journal of Engineering Technology, 2, 1, 16-21

To study the rolling properties of a radial tire, an accurate 3D 195/60R14 tire model is established. The modal includes the geometric nonlinearity due to large deformation, material nonlinearity, the anisotropy of rubber-cord composites, the nonlinear boundary conditions from tire-rim contact and tire-pavement contact. The model can be used to simulate the changes of a rolling tire and calculate the tire deformation for various operating conditions. The profile of inflated tire is studied experimentally and numerically. The simulation result is in good agreement with the test result. Some contact problems, such as the tire deformation, the shape of contact area, the contact pressure distribution, are discussed in detail.

空気力による昆虫翼の弾性変形がいかにしてキャンバーをもたらすかについて，未だに明確でないようである．そこで本研究では，昆虫羽ばたき翼のキャンバー生成における翅脈の力学的役割を解明するために，それらの形状簡略化モデルを提案する．提案モデルにおいては，翅脈をその機能に応じて幾つかの領域に分け，各領域における大域的構成関係を対応するはりによって表す．さらに，翅脈が支える翼膜は長方形のシェルによって表す．キャンバー生成で支配的な空気の動圧によるモデル翼の静的変形を考える．実際の昆虫と整合した設定の提案モデルに，幾何学的非線形性を考慮した有限要素解析を適用する．この結果，昆虫羽ばたき翼のキャンバー生成における翅脈の力学的役割を明らかにする．

A redesign of canard control-surface of an advanced all-metallic fighter aircraft was carried out by using carbon fibre composite (CFC) for ribs and panels. In this study ply-orientations of CFC structure are optimized using a Genetic-Algorithm (GA) with an objective function to have minimum failure index (FI) according to Tsai-Wu failure criterion. The redesigned CFC structure was sufficiently strong to withstand aerodynamic loads from stress and deflection points of view. Now, in the present work CFC canard structure has been studied for its buckling strength in comparison to existing metallic design. In this study, the existing metallic design was found to be weak in buckling. Upon a detailed investigation, it was revealed that there are reported failures in the vicinity of zones where initial buckling modes are excited as predicted by the finite element based buckling analysis. In view of buckling failures, the redesigned CFC structure is sufficiently reinforced with stringers at specific locations. After providing reinforcements against buckling, the twist and the camber variations of the airfoil are checked and compared with existing structure data. Finally, the modal analysis has been carried out to compare the variation in excitation frequency due to material change. The CFC structure thus redesigned is safe from buckling and aerodynamic aspects as well.

Reducing wedge without generating camber is still a big challenge for today’s process automation systems for hot strip mills. Therefore, detailed transient 3D-models of the underlying severely asymmetric flat hot rolling processes have been developed by the authors with the help of the commercial FEM-package ©Abaqus Explicit. By utilizing suitably positioned edging rolls, the corresponding lateral force acting on the strip induces a lateral material flow inside the roll gap, leading to stress-redistributions such that the outgoing camber-curvature is drastically reduced. Systematic parameter studies performed so far revealed how the lateral edging force and the resulting strip camber-curvature depend on characteristic rolling parameters, such as slab width, thickness, initial wedge and thickness reduction. To understand the underlying highly non-linear elasto-viscoplastic forming processes inside the strip or slab in more detail, and to develop fast simulation-tools, semi-analytical model reduction approaches have been developed. This enables a quantitative analysis of the induced lateral material flow and the occurring stress-redistributions inside the roll bite. By introducing a lateral material transfer parameter directly correlated to the camber-curvature, an analytical relation could be derived for the bending moment (and external work) that has to be applied to eliminate the camber of the strip or slab. These analytical predictions, although based on rough simplifications, correspond quite satisfactorily with those attained by 3D-FEM simulations.

Small axial fan which diameter is less than 100mm has been used widely as cooling device. Experimental studies have been carried out in order to improve performance and reduce noise of small axial flow fan. In this report, small axial flow fan with diameter of 92mm popularly used at a personal computer or a workstation was chosen, influence of design parameters of impeller such as camber of blade, maximum camber point of blade, cross sectional figure of blade, skew angle of blade and roundness of blade edge on aerodynamic performance and noise were investigated.

SCOPUS: ar.j, info:eu-repo/semantics/published

Facultad de Ingeniería Mecánica. Maestría Ciencias en Ingeniería Mecánica In turbomachinery the major efforts are concentrated on the parametric design of the runner blades, which can be seen geometrically as free-forms of considerable complexity. Therefore, the search for the optimal shape of the flow passage through the channel by means a flexible parametric runner blades approach remains as a fundamental effort of the designer and it is up today a matter of the research field. Researchers classify the blades parameterization in two main groups: those that use a sectional approach and those that use surface zones. In regard to their potential for design optimization purposes, the sectional approaches provide different variables for a large number of blade profiles; however, all of them present the same disadvantage: any increase in the number of required sections to define the blade shape, it becomes with an increase in the number of variables or parameters involved with the design process. The goal of the present project it is to introduce a new technique with the sectional approach for any section distribution along the blade direction without increasing the blade design parameters. The airfoils geometry was taken according to the relations given by for the airfoil numerical NACA code (with four and five digits). By varying the shapes of the curves, which represent the blade parameters distribution on each section along the spanwise direction, the initial data for the graphical construction of a real long and twisted 3D blade was found. En el diseño de turbomáquinas los mayores esfuerzos del diseño paramétrico se concentran en el diseño de los álabes del rodete, los cuales pueden ser considerados geométricamente de forma libre de considerable complejidad. Por lo tanto, la búsqueda de la forma óptima del paso de flujo por el canal mediante un enfoque paramétrico flexible de los álabes, continúa siendo un estudio fundamental por parte del diseñador y es todavía hoy en día un campo actual de investigación. Los investigadores clasifican la parametrización de los álabes en dos grupos principales: los que emplean un enfoque de sección transversal y aquellos que usan zonas de superficie. En lo que respecta a su potencial en la optimización del diseño, el enfoque de sección proporciona diferentes variables para un gran número de perfiles de álabes. Sin embargo todas éstas presentan la misma desventaja, cuando se incrementan el número de secciones requeridas para definir la forma del perfil, se incrementa también el número de variables o parámetros involucrados en el proceso de diseño. El objetivo del presente proyecto, es presentar una nueva técnica paramétrica con el enfoque de sección, para la distribución de secciones a lo largo del perfil, con un número importante de secciones sin incrementar el número de parámetros de diseño del álabe. La geometría de los álabes se toma de acuerdo con las relaciones dadas por el código numérico de perfiles aerodinámicos NACA (con cuatro y cinco dígitos). Mediante la variación de las curvas del perfil, que representan la distribución de los parámetros del álabe en cada sección a lo largo de la altura del mismo, se encontraron los datos iníciales para la construcción gráfica de un álabe real de gran longitud y con torcedura en 3D.

Background The rear-wheel camber, defined as the inclination of the rear wheels, is usually used in wheelchair sports, but it is becoming increasingly employed in daily propulsion. Although the rear-wheel camber can increase stability, it alters physiological performance during propulsion. The purpose of the study is to investigate the effects of rear-wheel cambers on temporal-spatial parameters, joint angles, and propulsion patterns. Methods Twelve inexperienced subjects (22.3±1.6 yr) participated in the study. None had musculoskeletal disorders in their upper extremities. An eight-camera motion capture system was used to collect the three-dimensional trajectory data of markers attached to the wheelchair-user system during propulsion. All participants propelled the same wheelchair, which had an instrumented wheel with cambers of 0°, 9°, and 15°, respectively, at an average velocity of 1 m/s. Results The results show that the rear-wheel camber significantly affects the average acceleration, maximum end angle, trunk movement, elbow joint movement, wrist joint movement, and propulsion pattern. The effects are especially significant between 0° and 15°. For a 15° camber, the average acceleration and joint peak angles significantly increased (p < 0.01). A single loop pattern (SLOP) was adopted by most of the subjects. Conclusions The rear-wheel camber affects propulsion patterns and joint range of motion. When choosing a wheelchair with camber adjustment, the increase of joint movements and the base of support should be taken into consideration.

The purpose of the current study was to investigate the effects of different wheel sizes, with fixed gear ratios, on maximal effort mobility performance in wheelchair athletes. 13 highly trained wheelchair basketball players, grouped by classification level, performed a battery of 3 field tests in an adjustable wheelchair with 3 different wheel sizes (0.59 m, 0.61 m and 0.65 m). Performance was assessed using the time taken to perform drills, with velocity and acceleration data also collected via a wheelchair velocometer. 20 m sprint time improved in the 0.65 m condition (5.58 +/- 0.43 s, P = 0.029) compared with 0.59 m (5.72 +/- 0.40 s). Acceleration performance over the first 2 (P = 0.299) and 3 (P = 0.145) pushes was not statistically influenced by wheel size. However, the peak velocities reached were greater in the 0.65 m condition (4.77 +/- 0.46 m.s(-1), P = 0.078, Effect Size [ES] = 0.63) compared with 0.59 m (4.61 +/- 0.40 m.s(-1)). Impact velocity, calculated as the change in velocity from the onset of a push to the following impact peak, to define coupling performance, was also significantly improved in 0.65 m wheels (0.14 +/- 0.14 m.s(-1), P = 0.006) than 0.59 m wheels (0.05 +/- 0.10 m.s(-1)). The time taken to complete the linear mobility (P = 0.630) and the agility drill (P = 0.505) were not affected by wheel size. Finally, no significant interactions existed between wheel size, classification and any performance measure. To conclude, larger 0.65 m wheels improved the maximal sprinting performance of highly trained wheelchair basketball players, without any negative effects on acceleration or manoeuvrability. Improvements in sprinting were attributed to a combination of the reduced drag forces experienced and improvements in coupling thought to be due to the lower angular velocities of the wheel/hand-rim when developing high wheelchair velocities in larger wheels.

Initially, cross country skis were used to move from place to place through the snow in winter. Now mainly it is performed in recreational and competition environments. Its intuitive basic technique, the direct contact with nature and the health characteristics makes this sport a very attractive activity for a lot of people from a large range of ages.In competition, technique is brought to the extreme and it is conditioned by many characteristics. In this case equipment is very important for good performance and skiers look for the optimum ski. Here is where special test benches and tools are used to evaluate mechanic behaviors and match up the skier with the equipment.Methods to evaluate skis already exist, some of them old but yet reliable. However, in the last 20 years test methods have improved a lot with new devices and new data is obtained, which is decisive in the ski market and competition. This project focuses on different techniques to obtain mechanical properties of the cross country ski. The methods should allow the interested to evaluate the performance of the ski as well as match it up with the best skier. Validerat; 20120620 (anonymous)

Objective: To examine wheelchair athletes' perceptions of wheelchair configuration in relation to aspects of mobility performance.Methods: Nine elite wheelchair athletes from wheelchair basketball, wheelchair rugby and wheelchair tennis were interviewed using a semi-structured format. Interview transcripts were analysed using an Interpretative Phenomenological Analysis, whereby emergent themes with common connections were identified and clustered into 3 superordinate themes: (i) performance indicators; (ii) principal areas of wheelchair configuration; and (iii) supplementary areas of wheelchair configuration.Results: Participants revealed that stability was the most important contributor towards successful performance. Whilst there was some agreement amongst participants on how manipulating most areas of wheelchair configuration influenced performance, opinions were divided as to whether camber had a positive or negative effect on straight line performance.Conclusion: Experienced athletes seemed to display a good understanding of how modifying wheelchair configurations can affect sports performance, yet the methods offered for identifying optimal settings were extremely subjective. Therefore, future quantitative research into specific areas of configuration is imperative to identify these optimums and to inform athletes about the decisions they make when configuring a new sports wheelchair.

Accurate camber prediction in prestressed concrete bridge beams is important to all parties involved in bridge design and construction. Many current prestress loss prediction methods, necessary for proper camber calculation, were developed many years ago and are predicated on assumptions that may no longer be valid as higher strength concrete, wider beam spacing, and longer span lengths become more commonplace. This throws into question which models are appropriate for use in camber calculation by the bridge engineers and contractors of today. Twenty-seven high-strength concrete modified 79 in. Bulb Tee beams with a design compressive strength of 9,000 psi were periodically measured to determine camber growth. Most available models for concrete creep and shrinkage were used to calculate creep and shrinkage strain. The modulus of elasticity equation of each model was used to predict modulus of elasticity of the studied mix. The Shams and Kahn compressive strength and modulus of elasticity equations were modified in order to approximate measured modulus of elasticity. The creep, shrinkage, and modulus of elasticity equations were used as inputs to an incremental time step method. The time-dependent change in beam curvature calculated by the time step method was used to calculate theoretical camber using the Moment-Area method. Predicted camber, using inputs from each considered model, was then compared with measured camber to determine the most accurate camber prediction models. Season of casting was also examined to determine what, if any, affect ambient temperature has on camber growth. For the studied beams, the Shams and Kahn Model for creep, shrinkage, and modulus of elasticity, used as inputs for an incremental time step analysis, were found to most accurately predict camber values. Lower concrete compressive strength was observed for test cylinders from beams cast in summer versus beams cast in winter. Differences in beam deflection based on season of casting showed mixed results. Master of Science

Prestressed concrete structural members camber upwards or downwards depending upon the location of application of prestress force. Identical members do not camber equally due to variability of the factors influencing it. Differential camber in the beams, if significant, results in excessively tall haunches or girder top flange extending into the bottom of the slab. For adjacent members like deck bulb-tees and box girders that are to be transversely post-tensioned the differential camber causes problems during the fit up process. This variation is undesirable and hinders the smooth progress of construction work if not properly accounted for at the design stage. Various factors influence camber and camber growth in prestressed members. Some of the factors are concrete strength and modulus, concrete creep and shrinkage properties, curing conditions, maturity of concrete at release of prestress force, initial strand stress, climatic conditions in storage and length of time in storage. Combinations of these variables result in variation of camber of otherwise similar beams at the time they are erected. One way to increase the precision of camber estimation is to use Monte Carlo simulation based upon the randomized parameters affecting the camber and camber growth. In this method, the parameters, in the form of a probability distribution function, are combined and passed through a deterministic model resulting in camber and camber growth prediction with narrowed probability bounds as compared to single definite value given by most contemporary methods. This outcome gives the expected range of cambers for a given girder design. After determining the expected range of camber, the ultimate goal is to provide guidelines for using unbonded monostrands for camber adjustment. Master of Science

The objective of this research was to determine if differential camber of prestressed concrete girders could be reduced by accurate prediction of initial camber at release of prestress. Maturity at prestress transfer was used to calculate modulus of elasticity for predicting camber at release. The research consists of a literature review of maturity methods, testing of a standard concrete mix to determine strength and modulus functions and measurement of girder camber and maturity. Both the Nurse-Saul and the Arrhenius maturity models were evaluated. Maturity relationships were developed for concrete mixes containing Type II and Type III cements. A relationship of modulus as a function of maturity was developed. Seven girders were tested. Camber predictions within 0 to ¼ in. of actual camber were obtained using modulus of elasticity calculated from a maturity based function. Comparison was made between maturity based modulus and standard strength based modulus models. Camber predictions based on modulus calculated based on field cured cylinder strengths were within 0 to ½ in. Master of Science

The recently developed LuGre model describes the 3D tire friction dynamics given in brush representation. The model has three-state lumped-parameter form and an analytical solution for tire static curves. It is simplified based on the assumption of constant slip speed along the contact patch length. This assumption is released in this paper in order to extend the model with several secondary, but potentially important effects such as camber, carcass compliance, conicity, ply-steer, and rolling resistance. Two approaches of introduction of variable slip speed effect are considered. The first one is based on stepwise approximation of slip speed along the contact patch length, and the second one includes a specific spatially-distributed additive deflection term. Both approaches provides preserving the three-state lumped-parameter model form and an analytical steady-state solution. Qualitative and quantitative validation results point to consistency and benefits of the proposed model extensions.