Movements of a human arm are observed in cases of a spike of a volleyball, a stroke of a tennis ball with a racket, and a hitting action of a wooden hammer on a concrete block. A small acceleration pickup is fastened on a wrist and the shock acceleration values and their waveforms are recorded. The accelerations of the wrist in case of the volleyball are about 72g, those in case of the tennis are about 12g, and those in case of hitting actions of the hammer are 2g in these observations.
New equations concerning with the motion and electric current of the step motor for time-piece are introduced at the beginning of this paper, taking the eddy current of the stator into consideration. The results of the simulation with equations adopted as above are compared with those of experiments carried on several motors, and it is ascertained that the equations are almost consistent with the behavior of the stepping motor. The wave form of the current taking place by single voltage pulse and several experimental data regarding to motor characteristics are used as the reference for the simulation. These experimental results are obtained by use of several types of stepping motor. The process of the simulation stated in this paper is one of the methods to decide the motor parameters which are the constants involved in the equations and characterize a stepping motor. The equations with these parameters will be used effectively for the motional analysis of stepping motor by simulation.