Active damping of a vibrating string
نویسندگان
چکیده
This paper presents an investigation of active damping of the vertical and horizontal transverse modes of a rigidly-terminated vibrating string. A state-space model that emulates the behavior of the string is introduced, and we explain the theory behind band pass filter control and proportional-integral-derivative (PID) control as applied to a vibrating string. After describing the characteristics of various actuators and sensors, we motivate the choice of collocated electromagnetic actuators and a multiaxis piezoelectric bridge sensor. Integral control is shown experimentally to be capable of damping the string independently of the fundamental frequency. Finally, we consider the difference between damping the energy in only one transverse axis, versus simultaneously damping the energy in both the vertical and horizontal transverse axes.
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