| The engineering background of the power unit’s anti-shock design is introduced briefly.Then the structural dynamics’ methods of modeling and calculating for shock and vibrationcontrol is summarized. The shock control strategies and thedevelopment oftechnology aboutactuators home and abroad are also investigated. The conflict between vibration control andshock reduction is analyzed, which is expected to be solvedthroughtheapproachofshock-and-vibration-integratedsemi-active control based on dynamicabsorbers.In order to calculate the dynamic response of the complicated isolation system withdynamic vibration absorbers, the multi-rigid body method, the spectrum analysis method andthe Newmark step-by-step integration method are used. With the comparison between thecalculation resultsby programs codedin MATLAB and finite element method by ANSYS,respectively, the accuracy of coded programs is verified.The research of shock response assessment and anti-shock laws of single-layer isolationsystem, double-layer isolation system and floating raft isolation system are carried out. Theparameters’ optimization of different systems is then accomplished with the timedomainresponse calculated through the step-by-step integration method.A modified type of electro-magnetic semi-active dynamic absorber, which has betterstability, more compact structure, lighter weight and wider frequency tuning range comparedwith the conventional type of actuator, is designed and researched experimentally. A series ofexperiments on current-frequency characteristics and single-frequency vibration control arecarried out.A program using Labwindows/CVI development environment is composed to realize thestrategy of shock-and-vibration-integrated control. Asimulativefloating raft isolation system isdesigned and constructed, on which the experimental study on shock control and united test ofthe entire control system consist of software, data acquisition card, actuator, etc, are also doneto confirm the control performance of the system.The results illustrate that the software has a good performance on frequency’s following and working states’ switching between shock andvibration control state. |
