Intergrated Design Of Active Vibration Control Platform For Thin-wall Shaped Surface Vibration

Large-scale thin-walled components are widely used because of superior mechanical properties,especially in the aerospace field.Thinwalled components can reduce structural mass and reduce flight energy consumption.Due to the large geometric size,small thickness,complex shape,and low structural rigidity of thin-walled parts,surface vibration is easily caused during the machining process,resulting in high machining difficulty and low precision of the machining surface.In order to solve these problems,this paper designs an active vibration control platform based on the principle of electromagnetic direct drive.The platform converts the rotation actuator shaft into the output of the support head of the platform to control the vibration of the thin-walled components.The main contents of this thesis include the following aspects:(1)Design and experiment verification of the electromagnetic direct drive actuators.Based on a new electromagnetic drive mechanism,the theoretical study of the permanent magnet model,electromagnetic torque model and magneto static torque model is carried out,and the results serve as the theoretical basis for the design of electromagnetic actuators.Combined with the design parameters of the electromagnetic actuator,the magnetic circuit design and structure design of the actuator are performed.The finite element analysis(FEA)is used to perform strength analysis and modal analysis to verify the design rationality.Finally,the output performance of the electromagnetic direct drive actuator was tested with experiments.(2)Design,system analysis and performance test of active vibration control platforms.Firstly,the overall scheme of active control of thin-wall vibration is introduced,and a motion conversion mechanism is proposed.Then overall design of the platform is completed.After that,the dynamic system analysis of the platform is conducted,and a nonlinear electricalmagnetic-mechanical coupling model is established.Then,by making reasonable assumptions,a simplified linear model is obtained,and the output characteristics of the system are simulated with MATLAB Simulink.Finally,in order to verify the reliability of the theoretical model and the actual performance of the platform,an open-loop experiment of an active vibration control platform is implemented.(3)Research on signal tracking experiment and active vibration control experiment.Based on LMS adaptive control algorithm,the tracking experiment and vibration control experiment of the platform are carried out.The signal tracking experiment tests the platform’s ability to track the expected displacement.The experimental result shows that the platform achieves a tracking accuracy of 93.05% for a displacement signal with an amplitude of 1.5mm and a frequency of 6Hz.The vibration control experiment tests the control efficiency of the platform for the vibration of thin-walled parts.The experimental result shows that the vibration control platform can reduce the vibration amplitude by 71.3% for a displacement signal with a frequency of 10 Hz.