It is difficult problem to make a human like ensemble system, In this research, we analyzed the rhythm interaction between performers by measure the hutting time and hitting cycle of keyboard performance. From the analysis, we discovered importance of two effects, which are hitting lag and hitting lag variation bctween performers. We modeled its dynamics by non-linear phase oscillator, which has two kinds of interaction mechanism, which represents the effect from hitting lag and the effect from hitting lag variation. We evaluated this system with human performer and discovered that the coupling constant of each model determine the dynamics of performance and the balance of these two interactions is important to realizc human like ensemble. Finally we show the best parameters of the models and realize human like ensemble system. Key Words : mutual entrainment, ensemble system, phase oscillator, performance, phase difference
Fig.l Music score for ensemble Fig.Z Definition of each indicator Table I Correlation coefficient between hitting lag variation /,(n) and hitting cycle variation c,^(n),cn(n) in e'arch d Average Table 2 Correlation coefficient between hitting lag /(n) and hitting cycle variation c,^(n),c,,(n) in each d Averaqe -+ hitting lag variation -r- hitting lag
c(n) = klt n(n) - r,qt)\ + cr
Human Machine
T. SICE Vol. 4l No. 8 August 2005
70 8( 20 30 $ JO". 60 70 8C Fig.6 Temporal development of phase difference in each K and A 20 0.t I Recpency (l /Beat) \t\ V y = 5522 x{'r' # =O?2 v = 6987 x-o'ro # = 0.28
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