Impactor calibration: Comparison between accelerometric measurements and extensometric processed data

We have developed a new prototype of impactor based on an energy restitution of a torsion bar. This device provides controlled impact velocities and energies of a fist comparable to those of met in boxing sport and martial arts. The analysis of the fist acceleration during the interaction with a target allows one to characterize the punch as well as dampening efficiency for protective sport equipments. The impactor was endowed with an accelerometer directly to acquire acceleration data values during the punch. On the other hand, an extensometric sensor has been used to follow the instantaneous angular position of the fist. The second-derivative of the angular position has been calculated in order to assess the impactor acceleration. Accelerometric and extensometric processed data are compared and discussed.