The equations for wheelchair caster wheel shimmy are presented along with experimental data. The report includes the theory and performance of single wheel casters for a variety of tires, and a new design for wheelchair casters using a grooved dual-tread tire or co-rotating caster wheels. The dual-tread tire was found to significantly inhibit caster shimmy. The turning resistance due to a groov...

The objective of this study was to compare the rolling resistance of four common manual wheelchair tires (two pneumatic and two airless solid) and the solid tires used on a commercially available force- and moment-sensing wheel. Coast-down tests were performed with a wheelchair positioned on a two-drum dynamometer. Within each of three load conditions, tire type had a significant effect on roll...

Tire-road friction is the most important piece of information used by active safety systems. However, most conventional friction estimation/ detection methods are accurate only within the non-linear region. In addition, such methods require numerous sensors, such as yaw rate sensors, acceleration sensors, and steering angle sensors. In this paper, a friction estimation method using a tire vibra...

A closed-loop drive–vehicle–road–environment system (DVRES) model was established using Adams/Car and Matlab/Simulink. Dynamic responses of lateral tire forces based on tire–road side friction and road geometric characteristics are used to investigate vehicle side slip for geometric design safety estimation. The root mean square, the maximum values of lateral tire forces, comfort limit on curve...

Abstract Sudden tire failure (a blowout) is a major cause of traffic accidents, many of them involving fatalities. If the automobile can quickly identify that a blowout has occurred, the braking system can be programmed to carry out braking and stability control to slow down the vehicle steadily. Hence, timely identification of a blowout or severe leakage is a key enabler of using the braking s...

Being a typical representative of detailed mechanical tire models ‘below’ true FEM models, the author’s model family FTire (Flexible Ring Tire Model) will be discussed in greater detail here. FTire development started in 1998, using certain ideas and numerical concepts of the author’s ‘coarse-mesh’ FE model DNSTire ([1], [2], [4]) and the spatial non-linear ‘rigid-ring’ model BRIT ([3], [5], [6...

Simulation results of near infrared (100- to 200-THz) fishnet-structure negative-index metamaterials (NIMs) with single and multiple functional layers exhibit bi-anisotropy - inhomogeneous asymmetry - due to the presence of a sidewall-angle. The influence of sidewall-angle resulting from realistic fabrication processes is investigated through the retrieved effective parameters by both a three-d...

Our aim was to examine hemodynamic implications of intravascular stenting in the canine venous pouch (sidewall or straight-vessel) and rabbit elastase (curved-vessel) aneurysm models. Flow dynamics in stented (Wallstent) and nonstented versions were studied by using computational fluid dynamics simulations and in vitro flow visualization, with a focus on stent placement effects on aneurysmal fl...

This paper deals with the level of detail that is necessary for representation of tread pattern in finite element tire models. Different methods for creation of tire tread mesh are systematized by two different criteria: the most common approaches and the finite element analysis type. Some of the representative approaches found in literature are given in more detail and their advantages and dis...

ERP system is based on the ideas and methods of supply chain management,and the integrated information management system is developed on the basis of MRP II, it represents the development trend of management revolution of manufacturing enterprises in the information age. [1]ERP system has strong application values in the tire enterprise, its main purpose is to allocate and balance the enterpris...