Experimental Study Of Vibration Control Method Of Flexible Manipulator Based On Piezoelectric Ceramic Elements

Flexible manipulators have become a research hotspot in the field of robot due to their advantages of lightweight,fast response,low energy consumption and large load ratio.But because of its low stiffness,elastic vibration will be occurring frequently,thereby reducing the accuracy of operation and work.The suppression effect of a flexible mechanism can improve by using the appropriate suppression method.In recent years,in order to achieve vibration suppression,most of the researches have used piezoelectric ceramic drive devices to establish closed-loop control systems.However,the use of adjustable vibration suppression method has a significant control effect.The main contents of this paper are as follows:The dynamic equations of the flexible manipulator are established based on the theory of material mechanics and elastic mechanics,and the theoretical model of the flexible manipulator vibration suppression system is established.The modal analysis of the flexible manipulator is carried out in COMSOL.The vibration controller of the flexible manipulator of each order mode has been designed based on the vibration diagram in the first three modes of the flexible manipulator.In the modal analysis,the position of the largest bending deformation of the flexible manipulator is taken as the theoretical optimal position of the vibration control.The sensor voltage of the flexible mechanical arm vibration on optimal control position and nearby is obtained by the Labview data acquisition device.The flexible arm vibration suppression effect is analyzed by the change of the sensing voltage before and after the control.According to the experimental results,the flexible arm achieves the highest vibration suppression at its optimal control position under the first three orders of vibration,and the effectiveness of the optimal control position was verified.Based on the effectiveness of the optimal position of the active vibration suppression of the flexible manipulator,a flexible mechanical arm vibration suppression test system based on stepper motor is established.The time-domain signal diagram of sensing voltage of the flexible arm free vibration is processed by FFT,the vibration energy of the flexible arm is mainly composed of modal vibration of the first two modes.Take into account this,the vibration test of the flexible manipulator based on the stepping motor in the static bias state and the running state is studied respectively.According to the experimental results,it is concluded that vibration control is carried out in the optimal vibration suppression position of the flexible manipulator of the first and second modes.And the vibration control of flexible manipulator in the optimal vibration suppression position of the first mode can make it reach the stable state more quickly.