Patent ID: 7307208

Claim:
An automatic player musical instrument for producing tones, comprising: an acoustic musical instrument including plural manipulators selectively moved for specifying the pitch of said tones, and a tone generator connected to said plural manipulators and responsive to motion of said plural manipulators for producing said tones at the specified pitch; and an automatic player including plural sensors for producing detecting signals representative of a physical quantity expressing said motion, plural actuators selectively energized with a driving signal so as to give rise to said motion of said plural manipulators, and a controller connected to said plural sensors and said plural actuators for forming a servo-control loop and forcing said plural manipulators to travel on reference trajectories with said driving signal, the magnitude of which contains a loop gain component representative of response characteristics of said servo-control loop and a fundamental component representative of a constant load to be exerted on said plural manipulators, said controller categorizing said motion in a first sort of motion in which said plural manipulators change the direction of motion through a reversal longer than a critical time period or a second sort of motion in which said plural manipulators change the direction of motion through said reversal equal to or shorter than said critical time period, said controller enlarging said fundamental component around said reversal in said second sort of motion so as to keep said motion stable.