共查询到20条相似文献,搜索用时 156 毫秒
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压电复合材料薄壳结构振动主动控制 总被引:3,自引:0,他引:3
对表面粘贴压电元件的复合材料薄壳结构的应变驱动原理、振动控制方程进行了分析。建立了自适应控制系统,对粘贴了压电材料的玻纤/环氧圆柱壳的振动进行了主动控制实验。结果表明,压电自适应壳结构能对薄壳的振动进行有效抑制,同时使壳体噪声辐射得到显著衰减。 相似文献
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基于极点配置的柔性智能结构主动振动控制 总被引:4,自引:2,他引:2
对采用压电元件作为传感器和驱动器,基于极点配置法的柔性智能结构主动振动控制进行了实验研究,介绍了控制系统构成,实验结果验证了文章所述方法的有效性。 相似文献
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压电主动构件在桁架结构振动控制中的应用 总被引:1,自引:0,他引:1
压电主动构件是一种集作动和传感于一体的能承载的器件。文章主要针对研制的压电主动构件,通过实验研究其在桁架结构振动控制中的应用。结果表明,这种压电主动构件作为桁架结构的内控制源,可以有效地提高结构的模态阻尼、抑制结构振动。 相似文献
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振动和结构声的有源控制技术 总被引:2,自引:0,他引:2
近年来在有源噪声控制的基础上发展的有源振动和结构声的控制对降低低频振动和采用控制噪声辐射体的方法降低结构声是一种有发展前景的噪声与振动控制技术。本文讨论了振动和结构声的有源控制技术有一些基本内容并给出应用实例和实验结果。 相似文献
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振动主动控制是近年来发展起来的一种新的振动控制方法,振动主动控制需要外部施加能量。本设计中智能结构是利用传感器对结构的振动进行监测,驱动器在微电子系统的控制下准确动作,以改变结构的振动状态。与传统的振动主动控制方法相比,智能结构可以在不明显改变受控结构的质量和体积的条件下,达到自适应调节减振的目的。本设计以智能梁结构作为实验研究模型,研究了智能结构振动控制系统组成、实现原理;硬件电路设计包括A/D采样、CPLD外扩D/A、信号调理电路等,并通过TMS320F2812的CAN模块与上位机通信进行数据实时显示,达到很好的监测和控制目的。 相似文献
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空间红外相机为提高成像质量,采用脉冲管制冷机对大面阵红外探测器进行制冷和杜瓦封装,形成杜瓦组件,使探测器工作在深低温环境下。冷指与热端之间仅靠脉冲管的薄壁结构连接,径向支撑刚度偏低,无法承受卫星发射阶段的振动,需对冷指增加支撑结构;但为提高制冷效率,又需要尽量增大连接探测器的冷指与制冷机热端之间的结构热阻,以减少结构间漏热。传统的方案是在冷指与热端之间增加金属支撑柱,但该结构会带来附加的漏热,且因为连接刚度较大,会由于装配及加工误差在脉冲管焊缝处产生较大的结构应力,影响组件性能。提出一种基于玻璃纤维束的冷指支撑结构,利用玻璃纤维束的高抗拉刚度及低抗弯刚度提高冷指径向支撑刚度的同时减小其在轴向上的结构应力;同时,玻璃纤维束的超低导热系数和小截面面积可以极大的提高结构热阻,显著减小附加漏热。与传统方案相比,玻璃纤维束支撑加强结构在提高冷指支撑刚度同时,将冷指与热端之间的结构热阻增大为原来的3 730倍,解决了冷指支撑加强结构既要求抗振性能好、又要求漏热小的难题,可适用于各种类型的大面阵红外探测器的杜瓦冷指支撑结构。 相似文献
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This paper addresses the simultaneous control of vibration and static shape deformation of arbitrarily shaped thin-walled flexible payloads. During robotic assembly of these thin-walled parts, gravity and inertial forces acting on the parts may induce both static shape deformation and vibrations in the part sufficiently large that accurate and high speed assembly of these parts is hindered. Static deformations, which arise due to deformation of the part caused by its own weight under the influence of gravity, lead to misalignment of mating points of the parts. Unwanted vibrations, arising from inertial forces acting on the thin-walled parts as they are positioned for assembly, must damp out before parts can be mated, further hindering the process. In this work, a smart gripper with actuated contact points to grasp the flexible thin-walled parts is proposed to solve this problem. The smart gripper is capable of both part reshaping and active damping of unwanted vibrations of the part. It is fixed to a robotic manipulator and is comprised of multiple linearly actuated fingers with laser-based noncontact proximity sensors, and associated signal processing and controllers. In this paper, a simultaneous vibration and static shape controller is developed. The proposed controller is a composite modal controller in conjunction with a quasi-static modal filter and a bias Kalman filter, which is synthesized based on the reduced-order dynamic model of the flexible payload. A near industrial practice demonstration of the feasibility of the proposed approach is carried out using a proof-of-concept smart gripper to manipulate an automotive fender. Experimental results indicate that unwanted vibrations are successfully damped out, allowing faster cycle times for an assembly process, and static shape deformations are corrected, allowing accurate positioning of parts for assembly. 相似文献
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Roozen N.B. Koevoets A.H. den Hamer A.J. 《Mechatronics, IEEE/ASME Transactions on》2008,13(3):325-334
Lorentz-force-induced vibrations in MRI systems cause significant acoustic noise levels during scanning, the main acoustic noise source being the vibrating gradient coil. In this paper, a novel active vibration control technique is presented to reduce vibrations of the gradient coil, and hence, achieve a reduction of acoustic noise during scanning. The active vibration control technique uses seismic masses that are actuated by means of piezo actuators to create forces on the gradient coil counteracting its vibrations. Using four seismic mass actuators, a vibration reduction of 3-8 dB at resonance frequencies is achieved, giving an overall vibration reduction of 3 dB for a typical field gradient (FE)-echo planar imaging (EPI) gradient sequence, as substantiated by measurements. Using eight actuators, an overall vibration reduction of 5 dB is predicted for this sequence. 相似文献