The Mechanical Aspects of Martial Arts: Total Time of Execution and Kinematics of Kaedah A

Abstract

The ability of Kaedah A as a technique to fend off an attack with bare hands is questionable since the estimated ordinary human minimal reaction time is 0.18 s while the offensive force can reach its target in less than 0.1 s. Therefore, this study aimed to analyze the effectiveness of Kaedah A based on its total execution time and to describe the kinematic characteristics of the hand movements during Kaedah A’s execution. The experiment was carried out using the motion capture method. The Kinect sensor detects the hand motion, while the Virtual Sensei Lite directly processes the motion capture through a digitizing procedure to prepare the coordinate data for further analysis. The execution of Kaedah A was repeated five times by four experienced Seni Silat Cekak Malaysia (SSCM) practitioners to investigate its accuracy and repeatability. The obtained data have provided the input for the trajectory mapping procedure for initial and end point identifications. Time difference, Δt, between these two points has demonstrated that the total time of execution for Kaedah A is less than 0.1 s. Further analysis involved smoothing out the obtained coordinate data in order to generate the polynomial equations of the motions of the hand during Kaedah A’s execution. Based on the velocity-time graph generated by the equation of motion, it can be concluded that the execution of Kaedah A has the features of a ballistic movement. The findings have provided useful data for reliability prediction as well as enhancement of Kaedah A’s execution.

This work is supported by Persatuan Seni Silat Cekak Malaysia, Universiti Teknologi MARA and Ministry of Education (MOE) Malaysia, Grant no. 600-RMI/FRGS5/3(76/2013).