Experimental and theoretical study of the oblique impact of a tennis ball with a racket

Abstract

The normal and the oblique impact of a tennis ball with a racket has been studied. An accurate setup has been built in order to provide consistent initial conditions for the impacts. Experiments have been done for a wide range of impact angles and initial velocities. The motion of the ball before, during and after the impact has been recorded using a highspeed camera with 10,000 frames per second. The impact has been divided into two phases, compression and restitution. An expression for the contact force has been provided. The coefficient of restitution and effective coefficient of friction have been analyzed experimentally. For low impact velocities, the coefficient of restitution is constant at different impact angles. The effective coefficient of friction changes as a function of the impact angle. The contact force expression has been determined for the compression and the restitution phases using the experimental data from normal impact experiments. The simulation and experimental results are compared and verified for the normal and the oblique impacts.

A Review of Elastic–Plastic Contact Mechanics

“…Many analytical, experimental, and numerical studies have been performed to simulate and predict various contact properties, such as the real radius of contact, stress distribution, and contact force. Spherical contact models are used by many researchers from different fields such as tribology, mechanical impact [31][32][33][34][35], and electrical contact [11,31,32,[36][37][38][39][40][41][42][43][44][45][46][47][48][49][50][51][52][53][54]. Even though the spherical geometry is often used to consider asperity contact, it can also be used to consider the flattening of particles between surfaces, such as in anisotropic conductive films [51] or in the presence of wear particles [55] and nanoparticles [50].…”

Ausgewählte Anwendungen von Stoßproblemen

“…Die meisten wissenschaftlichen Untersuchungen der Stoßdynamik im Sport sind dabei experimenteller Natur. Bei der theoretischen Analyse gelangen bisher Starrkörper-Modelle [89] und FEM-basierte Modelle [90] zur Anwendung 18 . An dieser Stelle bieten kontaktmechanische Modelle eine einfache, aber robuste "Zwischenlösung", da Starrkörper-Modelle das dynamische Verhalten oft nur unzureichend erfassen 19 und FEM-basierte Untersuchungen numerisch vergleichsweise aufwendig sind.…”

Impact Behavior of a Rotating Rigid Body with Impact and Viscous Friction

“…Different surfaces for the impact were considered: rod with a flat surface [1], sphere with a flat [2,3], rotor system into a film damper [4], elastic wedges [5], sphere on a beam [6], anisotropic bisinusoidal surface and a rigid base [7], cylindrical body with a rigid plane [8], superball [9], tennis ball with a racket [10], and 3D-printed polymers under collision with a rigid rod [11]. Different types of behaviors depending of the nature of the constituent materials of the impacting bodies were studied: elastoplastic impact [2,3,6,8,[12][13][14], nonlinear elastic [1,15], elastic [16], elastic-perfectly plastic [17], and nearly complete elastic [14,18].…”

“…e material properties were studied from the point of view of the influence of the impact behavior: incompressible isotropic [5], nanoparticles [15], 3D-printed polymers [11], transmembrane domains [19], stable CuO nanoparticle enhanced lubricants [16], Al-6061 instrumented spherical microindentation and microstructurally graded samples [20], and various finishes [21]. e direction of the impact is another factor to be considered in modeling the impact: normal [6], oblique [10,13,22], normal, and tangential [7].…”