Xiaoning Luo

Study on the fuzzy control technique for the power ultrasonic instrument

The nccessity of having the functions of the fiequency tracking automatically and the vibration amplitude control in the power ultrasonic vibration system is summarized in the paper. The approaches of the frequency tracking automatically by using a self-optimizing fuzzy control and the vibration amplitude control based on a self-modifying PID fuzzy controller in the power ultrasonic instrument are presented. The principles and stmctures of two fuzzy controllers are analyzed, and the design procedure is introduced in details. The experiments show that the robustness and the control accuracy of the system are improved by using these fuvy control techniques. A novel means of the vibration control in the power ultrasonic system is offered.

The identification of frequency domain model of ultrasonic vibration system

The identification of frequency domain model of ultrasonic vibration system by using least square method is discussed. The key frequency band is subdivided, in order to keep characteristic point of system invariability. An actual vibrating body is checked up, and the model coincides with the experiment result well. This identifying model can be extensively applied to many fields.