Maxine Mei Sum Kwan

The importance of being elastic: Deflection of a badminton racket during a stroke

Abstract The deflection profiles of a badminton racket during strokes performed by elite and world-class badminton players were recorded by strain gauges and subsequently analysed to determine the role of shaft stiffness in racket performance. Deflection behaviour was consistent in all strokes across all players, suggesting a controlled use of racket elasticity. In addition, all impacts occurred within 100 ms of each other, a duration in which deflection velocity provides an increase in racket velocity, indicating that the players were able to use racket elasticity to their advantage. Since deflection behaviour is a product of the racket–player interaction, further work is required to determine the effects of different racket properties and player techniques on the elastic response of rackets during strokes.

DYNAMIC EFFECTS OF BADMINTON RACKET COMPLIANCE

The racket is modelled as a cantilever beam composed of two beam elements of different mass and stiffness properties, representing the shaft and the head. Neglecting axial deformation, the dynamic response of the racket due to inertial and centrifugal effects is described by equations of motion derived using Hamilton’s principle [Yang et al., 2004]. Motion capture data from ten trials of a smash stroke were filtered and averaged to determine translational and rotational kinematic inputs to the model, producing the racket motion shown in Figure 1. A fourth order Runge-Kutta method was used for time integration.

Dynamic Model of a Badminton Stroke (P254)

The purpose of this paper is to contribute to the understanding of dynamic racket behaviour in badminton. The paper describes the development of a dynamic model of a badminton stroke based on experimental data. Motion capture and strain gauge experiments are performed to clarify the movement and accelerations of a badminton smash stroke. Subsequent data processing reveals that due to the speed and acceleration of the movement, neither of the two methods provides the complete picture of the racket’s dynamic behaviour, but computational processing of the combination of experimental data together with physical modelling of the racket mechanics allows for an understanding of the basic mechanisms underlying racket movement and deformation. The paper concludes that the elastic deflection of the racket creates a narrow window of opportunity during which the impact is enhanced by the racket’s elastic behaviour, and this window must be closely synchronized with the timing of the stroke.

Application of an Optimization-Based Method for the Kinematic Analysis of a Badminton Stroke From Motion Capture Data

In this paper, we demonstrate an optimization-based method for the calculation of positions, velocities, and accelerations of a badminton stroke from motion capture data. The results show a good agreement between the measured marker trajectories and a flexible kinematical model of the racket with the error between the measured marker trajectories and the markers in the model being in the range of millimeters.Copyright