L. Taraborrelli

Manchester Metropolitan University | MMU · Department of Engineering

Tennis racket design has changed from its conception in 1874. While we know that modern tennis rackets are lighter and have larger heads than their wooden predecessors, it is unknown how their gross shape has changed specifically. It is also unknown how racket shape is related to factors that influence performance, like the Transverse and Polar mom...

The tennis racket has developed since the origins of Lawn Tennis in the 1870s. This study investigated how the tennis racket developed from 1874 to 2017, using measurements and material classifications for 525 samples. Racket measurements covered geometric, inertial and dynamic properties, and the number of strings. Rackets predating 1970 were main...

Tennis racket properties are of interest to sports engineers and designers as it allows them to evaluate performance, review trends and compare designs. This study explored mathematical models that correlated to the mass moments of inertia of a tennis racket, both about an axis through the butt and about the longitudinal axis, using its dimensions,...

Tennis rackets have advanced significantly since the invention of the game in 1874, including innovations in both shape and materials. Advances in these design parameters have implications for racket performance, especially swing speed. This study tested one hundred rackets, spanning brands and eras, using simple, portable instruments in order to p...

Some studies of bicycle dynamics have applied the Whipple Carvallo bicycle model (WCBM) for the stability analysis. The WCBM is limited, since structural elements are assumed to be rigid bodies. In this paper, the WCBM is extended to include the front assembly lateral compliance, and analysis focuses on the study of the open loop stability of a ben...

The development of high performance wheelchairs and wheelchair simulators requires dynamic models taking into account the properties of tires. In this paper the properties of two wheelchair tires are measured by means of a rotating disc testing machine and are compared with the properties of bicycle tires, which have similar dimensions and structur...

Stiffness of structural elements has a significant effect on the dynamics of single-track vehicles, because it influences the stability of the typical modes of this class of vehicles (weave and wobble). Up to date no specific method for measuring the critical stiffnesses of front fork, chassis and swingarm is universally recognized. This measuremen...

The static and dynamic properties of the frame and the front fork of a single track vehicle play a critical role from the point of view of vehicle stability. A turning point in the study of motorcycle stability was established by the introduction of lumped stiffness elements to characterize the critical compliances of the motorcycle elements, this...

Static and dynamic properties of single-track vehicles components (such as frames, front forks and swing-arms) play a fundamental role from the point of view of vehicle stability, which is a key issue of single-track vehicles dynamics and safety. Nowadays, the stability of a vehicle is studied by means of multi-body codes, in which it is possible t...

In this paper the effect of front fork compliance on uncontrolled bicycle stability is analyzed. First the benchmark model of a bicycle is improved to take into account either torsion compliance or bending compliance of front fork, a lumped element approach is adopted introducing additional joints restrained by rotational springs and dampers. Two m...

The properties of tyres have a large influence on the stability of single-track vehicles. This paper focuses on the characterization of the dynamic properties of tyres. In the first section of the paper, modal analysis of the tyres is presented. Two motorcycle tyres and four scooter tyres are modally tested in order to measure the natural frequenci...

It is well known that front fork flexibility may have a significant effect on motorcycle stability. This work addresses the problem of developing lumped element models of the front fork from experimental results. The front forks of an enduro motorcycle and of a super sport motorcycle are characterized performing static, dynamic and modal tests by m...

Stability and safety of road vehicles are largely affected by tyre properties. Single-track vehicles are characterised by weakly damped modes of vibration (weave and wobble) and therefore this phenomenon is even more important. This article focuses on the study of both steady-state and transient properties of motorcycle and scooter tyres in the pre...

Stability of two-wheeled vehicles is influenced by the transient properties of tires, which are described in terms of the relaxation length, which is the distance that the vehicle travels before tire forces reach the steady state values. Relaxation length is often studied by means of rigid ring models, in which the belt of the tire is modeled as a...