【作者】 黄山云；

【导师】 陈照波；

【作者基本信息】 哈尔滨工业大学 ， 机械设计及理论， 2010， 硕士

【摘要】 在运载火箭的发射过程中,航天器所经历的力学环境非常恶劣,其不仅受到来自于火箭发动机工作时的随机激励,还受整流罩的气动激励、火箭分离的瞬态冲击等。为降低航天器在发射过程中受到来自于运载火箭的各种振动和冲击,迫切需要一种有效而可靠隔振平台,其中基于磁流变阻尼器的半主动隔振平台以其反应迅速(毫秒级),可靠性高(即使控制系统失效,仍能作为被动隔振器),适应性强(可达到与主动控制十分接近的控制效果),能耗小等特点,在运载火箭整星隔振领域中极具发展潜力。本文从整星隔振用磁流变阻尼器入手,在深入研究磁流变阻尼器几种基本模型的基础上,选定唯像的Bouc-Wen模型作为整星隔振用磁流变阻尼器的模型基础,并根据整星隔振用磁流变阻尼器高频解耦机构的机构和工作特点,提出修正的的阻尼器模型。为进一步研究整星隔振用磁流变阻尼器的动力特性,本文对实际的阻尼器进行动力特性实验,得到阻尼器力与位移随电流变化的数据。根据实验数据,利用粒子群优化算法,对阻尼器动力模型中的参数进行优化,从而得到实际阻尼器的计算模型。本文根据实际阻尼器的计算模型,针对两种阻尼器控制器的控制算法,利用Matlab/Simulink对其进行仿真对比分析,仿真的结果表明修正的Sigmoid函数控制器的控制效果要优于基于Sign函数的控制器。最后建立一个二自由度受迫振动系统,并利用阻尼器的计算模型和控制器模型对其进行半主动控制仿真,其中最优控制力由线性二次最优控制算法得出。仿真结果表明,对于阶跃和正弦激励,由整星隔振用磁流变阻尼器的力学模型和修正的基于Sigmoid函数控制器组成的半主动控制系统具有较好的振动控制效果。本文从理论上分析并建立整星隔振用磁流变阻尼器的力学模型,并对实际的阻尼器进行动力特性实验和模型参数优化,对磁流变阻尼器计算模型的建立具有普遍的指导意义。同时本文在阻尼器计算模型基础上利用改进的阻尼器控制器模型与二自由度受迫振动系统进行半主动控制仿真,在验证了模型的正确性的同时,也证明了振动半主动控制的有效性。更多还原

【Abstract】 In the rocket launch process, satellite or spacecraft experience of dynamic environment is very bad, the excitation is not only from the random excitation when the rocket engines working, but also the pneumatic incentive and the transient shock from the separation of rockets. In order to reduce the vibration and impact from satellite or aircraft launched by rocket, a reliable and effective platform is urgently needed. A semi-active vibration isolation platform has huge potential in the carrier rockets star isolation,which is based on the isolation of magnetorheological damper(MR damper) with its fast reaction (ms), high reliability (even the control system failured, it still can work as a passive isolation system), strong adaptability (very close to the control effect), low energy consumption, etc.Beginning with MR damper which used for Whole-spacecraft Isolation and according to the structure of MR damper high-frequency decoupling partment and its working characteristics, a modified damper model was proposed, which is based on intensive study of several basic mechanical model of MR damper and uses the Bouc-Wen model as the foundation model. For further studies in the MR damper dynamic characteristics, a dynamic characteristics of the damper experiment has been taken, and the damper force and the dependence of displacement on the current changes were obtained. Besides, According to the experimental data and using particle swarm optimization algorithm, the dynamic model of damper parameters were optimized, then the practical calculation model of damper was obtained.According to the practical calculation model of damper, two kinds of damper control algorithm were simuliated and compared by Matlab/Simulink. It is showed that the control effect of the modified Sigmoid function controller is better than that of Sign function controller. Finally a reconfigurates forced vibration system was established, and a semi-active control simulation was taken by the damper simulation model and the controller model. It is showed that, at the step and sine excitation, the MR damper mechanical model and semi-active control system based on the Sigmoid function controller has good effect on vibration control.This paper theoretically analysis the MR damper ,establish the mechanical model for real, and optimized the model parameters and the dynamics of the real damper .It is of prevalent meaning of guidance for MR damper modeling. Furthermore, based on the MR damp simulation model and modified controller model, the semi-active control simulation was taken for two degrees of forced vibration system, the results not only verifies the validity of the model but also shows that the vibration of the semi-active control is effective.更多还原