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Continuously variable transmission (CVT) offers many advantages to vehicle performance over traditional transmission technologies. A novel cam based CVT was proposed in US patent # 4,603,240, by J. Klovstad and J. Fortune [1], which has a cam input to drive an angle dependent, clutch actuated output shaft. Based on the patented CVT, a kinematic simulation, utilizing three dimensional CAD software was performed, creating a visualization and analysis model to ascertain system performance and feasibility. This article describes the mechanism created, limitation of the modeling software and the approach utilized to overcome these limitations. The resultant motion is then analyzed to ascertain the performance of the mechanism and determine the viability of the design concept. Key improvements to the system are proposed to the design, based on system performance through this analysis.

An experiment was designed to observe balance recovery movement of standing volunteers in public transportation situations, and attempt to predict it. A perturbation corresponding to a typical emergency breaking situation was applied to the platform on which the subjects were standing. The effect of three different postures, three acceleration profiles and two external constraints were studied. Movements were reconstructed using a three dimensional whole body kinematic model. The reconstructed kinematic data were reduced prior to the movement analysis. The simplified representation obtained showed that the balance recovery movement consists of a succession of four basic phases, and also allowed to highlight the influence of the experimental parameters. In order to evaluate whether the data generated can be used to predict the motion in arbitrary conditions, the response of the intermediate acceleration level tests was predicted by interpolation between the two extreme conditions.

An ideal constant velocity joint (ball-joint) would be a perfectly symmetric frictionless joint, with no clearance or interference between its perfectly rigid parts. Over the years, many kinematic models of such joints have been developed throughout the automotive industry, and they have supported important insights into the kinematic behavior and performance of ball-joints. Such models are based on an analytic approach, whereby equations prescribing the motion of the parts are first derived and then solved. The realism or accuracy of the simulation produced by such a model depends upon the degree to which important physical effects can be captured by the formulation. The extent to which this can be achieved is ultimately limited by the ability to solve the resulting systems of highly non-linear equations. This paper describes an alternative approach to kinematic ball-joint modelling avoiding this limitation.

A procedure for the initial design of a suspension concept with four independently driven and steered wheels is developed, whereby, steering angles above conventional values are considered. To fully exploit the potential of such vehicles, an autonomous closed-loop setup with integrated motion control is utilized. The goal is to obtain statements for an optimal suspension design and parametrization maintaining a general approach, while underlying black-box control and the vehicle configuration remains exchangeable. The investigation of the influence of the chassis parameters, with crucial impact on energy consumption, comfort and driving dynamics, namely camber, caster, scrub radius and the steering axis inclination (SAI) depending on a varying caster angle and SAI in relation to the steering angle will be focused. For this sensitivity analysis, an explicit behavioral-oriented model of the suspension is created.

With over-constrained suspensions (solid axle rear suspensions with four trailing arms and a track bar), the compliance in the bushings needs to be taken into account in order for the suspension to articulate. Most CAD (Computer Aided Design) software packages offer only kinematic joints for simulating mechanisms. These joints do not model the bushing compliance that is required in over-constrained mechanisms. In addition, during the early phases of design work, detailed bushing information is not known or available. This paper provides a procedure and automated methodology that can be used early in the design process to simulate the movement of over-constrained suspensions using simple kinematic joints.

The article presents a theoretical analysis of a roller pump design and a summary of the experiments. The pump is to provide high pressure for transmission, accessory drive, and other applications. A theoretical model was built to simulate the motion of the rollers and optimize the design. An experiment was conducted to prove the simulation. The mathematical model was built within constraints of rigid body mechanics. Comprehensive kinematic and force analysis was done through differential equations of motion. Obtained quantitative relationships include, on one hand, pump geometry, speed of rotation, and discharge/suction oil pressure, and, on the other hand, torque, dynamic interaction of relatively moving parts, and kinematic parameters of the roller. The model includes dissipate forces to account for hydraulic effects. Modeling these forces is beyond mechanics of solid body and is not considered at this initial stage of research.

General Motors has recently developed a front-wheel drive version of its two planetary two-mode transmission (2-MT) for a hybrid-electric vehicle powertrain [1]. This newer transmission includes two planetary gears with two transfer clutches and two braking clutches. With activation of designated pairs of these four clutches, four fixed-gear ratios between the transmission's input shaft and output shaft are obtained. In addition, activation of specific individual clutches gives two modes of operation whereby the IC engine speed is decoupled from the vehicle velocity thus providing an electrical continuously variable transmission (ECVT). This present paper extends the power-split analysis in [2] by deriving a safe-operating region (SOR) in the plane of IC engine speed vs. vehicle velocity for the four fixed-gear and two ECVT modes. This SOR is bounded by the speed limitations of the 2-MT components. Similar results are presented for the Toyota Hybrid System II (THS-II) transmission.

This paper presents an approach to suspension linkage design that avoids the geometry iteration process typically required to ensure specific kinematic behaviour in the design condition. It is built around a model of behaviour for linkages and consists of geometric constraints applied during the design process that guarantee the design condition kinematic characteristics of the linkage. The approach is described in sufficient detail for it to be implemented within a spreadsheet or a parametric CAD model. Several examples are given of how it can be used to configure well-known non-trivial suspension architectures, such as that of the 5-link.

Computer simulations are popular for modeling vehicle system dynamics. However, further refinement of the vehicle dynamic model is required for extensive use in the automotive industry. In this paper, the model refining procedure is illustrated by developing reliable kinematic models verified with laboratory test results; instrument test data; and a mathematical optimization method. More specifically, simple kinematic models are developed for reduced computation times using ADAMS. They are tuned by the gradient-based optimization technique using the results from a laboratory testing facility, which includes the compliance effect in order to use the kinematic models in dynamic simulations. Also the Magic Formula tire model is developed using the optimization method and tire property data for the STI (Systems Technology, Incorporated) tire model.

This is a proposed alternative to the Ackermann Steering Mechanism. Synthesis of a six member mechanism taking seven precision points is performed for an automotive steering mechanism. The maximum rotation of inner wheel is taken as 65 degree to attain still less turning radius. The mechanism has been compared with those achieved by Ackerman Steering Mechanism (ASM), Fahey Eight Member Mechanism (FEMM) and Pramanik Six Member Mechanism (PSMM). The suggested mechanism gives fairly the accurate result that falls above the ASM mechanism. The mechanism gives better end response leading to shorter turning radius.

The patho-anatomic alterations due to vertical loading of the human cervical column were documented and correlated with biomechanical kinematic data. Seven fresh human cadaveric head-neck complexes were prepared, and six-axis load cells were placed at the proximal and distal ends of the specimens to document the gross biomechanical response. Retroreflective markers were placed on bony landmarks of vertebral bodies, articular facets, and spinous processes along the entire cervical column. Targets were also placed on the occiput and arch of C1. The localized movements of these markers were recorded using a video analyzer during the entire loading cycle. Pre-test two-dimensional, and three-dimensional computerized tomography (CT), and plane radiographs were taken. The specimens were loaded to failure using an electrohydraulic testing device at a rate of 2 mm/s.

Limited data exist on the injury tolerance and biomechanical response of humans to high-rate, under-body blast (UBB) loading conditions that are commonly seen in current military operations, and there are no data examining the influence of occupant posture on response. Additionally, no anthropomorphic test device (ATD) currently exists that can properly assess the response of humans to high-rate UBB loading. Therefore, the purpose of this research was to examine the response of post-mortem human surrogates (PMHS) in various seated postures to high-rate, vertical loading representative of those conditions seen in theater. In total, six PMHS tests were conducted using loading pulses applied directly to the pelvis and feet of the PMHS: three in an acute posture (foot, knee, and pelvis angles of 75°, 75°, and 36°, respectively), and three in an obtuse posture (15° reclined torso, and foot, knee, and pelvis angles of 105°, 105°, and 49.5°, respectively).

Motorcycle segment is growing very fast in India. The average riding speeds are much less owing to the road conditions and traffic. The roads have a mix of both high undulations as well as smooth and flat surfaces on highways. Achieving a very good level of ride comfort on such rough & smooth terrains combined with an equally good level of handling in the speed range of 20 to 80 Kmph is a highly challenging task. Monoshock rear suspension is one of the options engineers can look at, to enhance the handling behavior of motorcycles without compromising on the ride comfort too much. Our work is aimed at building a generic analytical model of typical mono shock motorcycle rear suspension that will enhance the understanding of system kinematics and extending its application for optimizing the design towards a better performance of the complete motorcycle. Both direct mount and linkage mount monoshock suspensions are studied.

The objective of this investigation was to determine if the HVOSM accident simulation software could be used to model a vehicle with a modern McPherson strut type front (or rear) suspension system. HVOSM has previously been validated for simulation of double A-arm suspensions. To accomplish this task, kinematic models of both the McPherson strut and the double A-arm suspensions were evaluated using data from two vehicles with similar track width, wheel base and weight, but with the different suspension systems. The results of the study indicate the wheel track on a vehicle with a McPherson strut suspension system more closely follows the motions assumed in the development of the HVOSM models. Therefore, a user of HVOSM can utilize data from a vehicle with a McPherson strut suspension system and be confident the simulation is at least as accurate as if the vehicle had a double A-arm suspension.

The kinematic model of a generalized double-offset joint(DOJ) is presented. The relationship between the input and output angles of DOJ may be analyzed by solving the quartic equation for the angular displacement from the output shaft to the normal of the homokinetic plane. The sensitivities of the output angle are evaluated and the cause for the output angle error is investigated with the kinematic constants curves. A method is presented for simulating the relationship between the input and output angles in the case where there exist a clearances between an inner-race and the balls. Moreover, the relationship between the input and output angles of the actual DOJ and the deviation of the input axis relative to the output axis are precisely measured, and the case of the output angle error is investigated by the simulation the cause of output angle error.

Frontal impacts with reclined occupants are rare but severe, and they are anticipated to become more common with the introduction of vehicles with automated driving capabilities. Computational and physical human surrogates are needed to design and evaluate injury countermeasures for reclined occupants, but the validity of such surrogates in a reclined posture is unknown. Experiments with post-mortem human subjects (PMHS) in a recline posture are needed both to define biofidelity targets for other surrogates and to describe the biomechanical response of reclined occupants in restrained frontal impacts. The goal of this study was to evaluate the kinematic and injury response of reclined PMHS in 30 g, 50 km/h frontal sled tests. Five midsize adult male PMHS were tested. A simplified semi-rigid seat with an anti-submarining pan and a non-production three-point seatbelt (pre-tensioned, force-limited, seat-integrated) were used.

In order to have a windshield wiper system according to wiped area and kinematic behavior requirements since the early phases of vehicle development, this paper makes use of a MATLAB optimization function to optimize the windshield wiper system. The main goal is to achieve the maximum wiped area by optimizing wiper blades lengths and orientations. Parallel to that, constrains make the method finds the optimum kinematic design for the windshield wiper linkage in terms of mobility, available area to fix the linkage on body and the maximum range of the blades oscillatory motion. This optimization is applied on an existent windshield wiper system of a domestic passenger car to present the benefits of the developed model.

The fact that single-track vehicles do not necessarily roll without slipping must be taken into account in the analysis of certain motions of such vehicles. This paper deals with kinematical questions arising under these circumstances. Constraint equations are formulated for motions involving side slip unaccompanied by longitudinal slip, expressions for side slip velocities are developed, and comparisons are drawn between the kinematical consequences of assuming rolling without slip and rolling with side slip.

The Kinematical models and Emulation of muti-axle steering of off-highway vehicles had been researched in this paper,that included the kinematical model of dozens of steering linkages, the relationship model of the steering linkages, the minimum steering radius and the wheel alignment, the mathematical model of the steering linkages and the steering system, and the model of the stability of the vehicle. The theory and method of the linkages optimization of multi-axle vehicles had been researched with kinematics theory. The simulation had been done on the multi-axle steering linkages of a eight-axle(8 X 8) off-highway vehiele, and the optimal parameters of the linkages had been obtained accordin to the simulation result and the optimal theory.

In this paper, a Magneto-Rheological (MR) fluid semi-active suspension system was tested on a commercial vehicle, a domestic light bus, to determine the performance improvements compared to passive suspensions. MR fluid is a material that responds to an applied magnetic field with a significant change in its rheological behavior. When the magnetic field is applied, the properties of such a fluid can change from a free-flowing, low viscosity fluid to a near solid, and this change in properties takes place in a few milliseconds and is fully reversible. A quarter suspension test rig was built out to test the nonlinear performance of MR damper. Based on a large number of experimental data, a phenomenological model of MR damper based on the Bouc-Wen hysteresis model was adopted to predict both the force-displacement behavior and the complex nonlinear force-velocity response.