Design And Experimental Research On Long-span Space Structure Damping Control Device

GMM is a kind of material which can deform largely under the action of magnetic field, though can recover after removing it. This material can transform Electromagnetic Energy into Mechanical Energy or Acoustic Energy, reversely, the Mechanical Energy can be transformed into Electromagnetic Energy, so it is main kind of energy-transforming material. Under the effect of low intensity magnetic field, it can create strain of 10-3 order of magnitude, in addition, its better bearing ability, high efficiency on energy transforming and fast reaction are all beneficial. Giant Magnetostrictive Actuator made of this material are widely used on the fields of machine precision machining, vibration and noise reduction and sensing.Giant Magnetostrictive Actuator can create large strain and stress, low-voltage-driven, low frequency in middle intensity magnetic field, so it can be used as the driving device in active control system. The character of the material varies because of the composition and process, so the performance of the material can be recognized more precisely by means of experiment.A new kind of GMM used in long-span structure is discussed, and then its characteristic is researched by means of experiment. The theoretical research about active control is discussed. The main subjects are as follows:(1) Introduced the mechanism of magnetostrictive effect, its basic character, constitutive equation, and the intelligent control equation is deduce from the constitutive equation.(2) Based on the design experience, a new kind of actuator is designed to be applied on the field of active control. The curves about electric current versus force and electric current versus displacement are all deduced from the experiment, then the model of electric current driving is created.(3) The static and dynamic finite element equations of GMM constitutive equation are deduced. Then the sample is applied to test the feasibility of using GMM in the field of structure seismic resistant and damping, and the result is positive.