| 摘要 |
<P>PROBLEM TO BE SOLVED: To exactly and easily specify a half point in a half pedal region. <P>SOLUTION: When a displacement from end position of a pedal is started by driving the pedal to the end position and pressing a prescribed key for identifying, an elapsed time t is started to count the time, when displacement of the pedal starts from the end position. A detection signal ys of a soundboard sensor with respect to the elapsed time t is stored, an oscillatory waveform of the soundboard to be original waveform is completed from the sequence of the detection signal ys, and the peak values of the oscillatory waveform in positive side are connected so as to obtain an envelope curved line CA. An intersection point pE is obtained through linear approximation of the envelope curved line CA, and the point where ys value becomes zero is set as pS. The point for dividing a half region starting point stS and a half region ending point stE, specified based on the points pS and pE with a prescribed internally dividing ratio is determined at a position stH as the half point. <P>COPYRIGHT: (C)2008,JPO&INPIT |
