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针对机载振动敏感设备面临的日益苛刻的振动环境适应性要求,开展减振设计方法和应用的研究。分别对机载振动敏感电子设备的振动环境条件获取方法、振动许用条件的测试手段、减振设计参数的计算方法、减振性能评估的措施进行了详细的探索,解决了减振设计过程中缺少相关设计输入、输出和选型参数的困境。并基于该方法对某机载频率源进行了减振设计的应用,应用结果表明基于该方法设计的减振设计方案,具有很好的减振效果。相比于直接安装,安装隔振器后频率源的振动响应得到了有效的抑制,并且频率源的相噪得到了明显改善。加装隔振器后相噪值均满足设计要求,减振设计达到了预期目标,同时验证了该减振设计方法的可行性。 相似文献
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为了减弱振动对车载激光雷达测量精度和稳定性的影响,借鉴浮筏减振系统在船舶领域的成功使用,对其进行了浮筏减振布局设计。采用多刚体动力学建模方法对系统在简谐激励下的减振性能进行了分析,得出系统各处减振器参量对系统减振效果的影响。根据选定的减振参量,结合所选车型,经过计算得到激光雷达主体的传递率峰值,有效避开了汽车运输过程中的激振频率,且几乎在有效的激振频率范围内传递率曲线都小于1;经计算得到冲击作用下的振动量程没有越过减震器的有效减震范围,符合理论要求;通过振动状态下激光雷达和探空气球所测风速数据的对比,验证了减振设计对保证测量精度的效果;通过静止和模拟振动状态下激光雷达的锁频效果对比,证明了浮法减振设计在车载系统中应用的可靠性。结果表明,浮筏减振设计应用于车载测风激光雷达是合理的、成功的。 相似文献
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为减小振动对机载光电吊舱成像质量和稳定精度的影响,依据平行四边形原理、隔振理论及吊舱模态分析数据设计了无角位移隔振装置,该隔振装置能够将载机振动引起的角位移转化成线位移并有效地抑制线振动。对无角位移隔振装置进行了动态仿真分析,仿真结果显示最大线位移仅为0.7 mm,并能够在较短时间内迅速地衰减。利用光学测量法测量了无角位移隔振装置的减振效果,测量结果表明无角位移隔振装置最大角位移为10″,与以往采用金属减振器的隔振方式相比减振效果提高了一个数量级,基本实现了无角位移,减振效果非常明显。外场试飞图像效果也验证了无角位移隔振装置减振的有效性。 相似文献
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四、减振系统的设计计算减振系统的设计可按下列步骤进行: 1.根据给定的技术条件确定各方向外激振动频率和振幅(或加速度值),如振源有较宽的频率范围,则应确定出最低频率时的振动强度. 2.已知减振系统的尺寸、重量,确定设备重心位置,对应于各重心主轴的惯性矩J_x、J_y、J_z以及惯性半径i_x、i_y、i_z.设备重心可用计算法或实验法决定.用计算法计算如图5-9中设备的重心坐标为: 相似文献
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介绍特殊环境下发射机的三维减振设计,并运用有限元分析软件ANSYS,以实测功率谱为激励,分析其响应,从理论上分析此减振系统的合理性,提供了一种实际工程中减振设计及分析的方法。 相似文献
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A three-axis vibration isolation system using modified zero-power controller with parallel mechanism technique 总被引:1,自引:0,他引:1
This paper proposes a module-type three-degree-of-freedom vibration isolation system using modified zero-power control. Three vibration isolation modules are connected together using parallel mechanism to control 3-DOF motions. Each module consists of a common base, an individual middle mass and a common isolation table. The base to the middle mass is suspended by positive springs generated by active and passive system, and the middle mass and the isolation table is connected by negative spring realized by active-type modified zero-power control. The developed system could realize zero-compliance to direct disturbances as well as good ground vibration isolation. Furthermore, the isolation table is supported by a weight support mechanism for supporting heavy payloads. In the previous research, a concentrated middle mass with redundant actuators, in the vertical and horizontal directions, were used. Therefore, a vibration isolation system is proposed in this work using modular concept to overcome those drawbacks. Each module is controlled separately by decentralized control technique, and three modules can be used for three-degree-of-freedom of motion control. Therefore, no redundancy of actuator is occurred. Moreover, an improved zero-power controller is presented that can adjust negative stiffness instead of conventional zero-power controller. The results obtained from analytical and experimental studies show that the modular technique is reliable and efficient approach to vibration control, and represents a suitable alternative to the conventional active vibration isolation systems. 相似文献
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《Mechatronics》2022
Vibration is an inevitable excitation in the operation of the mechanical system, which reduces its reliability and service life. Therefore, a heavy-duty 6-DOF semi-active vibration isolation system (VIS) with magnetorheological (MR) damper was proposed in this paper. Firstly, A MR damper with large output force of 27 kN was designed. The properties test results showed that the dynamic range (the adjustable multiple of damping force) of the damper is as high as 15, which has excellent dynamic performance. And a Bouc-Wen model which can accurately describe the mechanical behavior of the MR damper was established. Secondly, the prototype of the MR 6-DOF vibration isolation platform (VIP) with cubic structure was developed. Thirdly, a on-off semi-active control strategy was proposed for the MR 6-DOF VIP. The numerical simulation results showed that the semi-active VIS can effectively isolate vibration in the working frequency domain. Finally, the vibration experiment on shaking table was carried out. The test results showed that the designed heavy-duty MR 6-DOF semi-active VIP can control the load's attitude in real-time according to the system state. Compared with the current of 0 A, the vibration isolation effect of the on-off control is improved by 63.27% in the resonance region. The MR 6-DOF VIP can effectively reduce the vibration transmitted to the isolated system through the platform. 相似文献
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航天器在轨运行过程中,由于内部存在多种活动部件,会使结构体产生微小角振动,微小角振动呈现振幅较小、频率较高的特点,微小角振动会造成光学载荷成像质量的下降。光纤陀螺从组成原理上具有宽频带和高灵敏度的特点,能够输出采样周期内的角度增量,可以作为微小角振动测量部件。但是,基于航天器整体时序的综合考虑,无法对光纤陀螺进行均匀采样,提出了非均匀采样条件下的频谱分析方法,将经过非均匀采样得到的整周期时间序列进行傅里叶变换,得到原始信号的幅值和频率,进而实现微小角振动的高精度检测。通过数字仿真和六自由度微振动台试验验证了上述方法的可行性,检测精度优于0.04。 相似文献
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利用传输光纤中后向瑞利散射光携带有光纤位置、外界振动等信息的特点,采用光纤迈克耳逊结构构成干涉型光时域反射仪,有望以分布方式传感沿光纤的微小振动信号.文中设计了一种新型结构的分布式光纤振动传感器,该传感器用3dB耦合器将波长为1310nm的红外激光分为两路相干光:参考光和传感光,它们中的后向瑞利散射光在耦合器处发生干涉,干涉信号的变化点对应于振动点所在的位置.将没有振动信号、加微小振动信号和加损耗干扰三种情况分别作用于传感光纤并进行了试验对比.结果表明,在微小振动的情况下,光强变化微弱;加损耗时,光强变化显著,定位准确. 相似文献
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搭建了基于布里渊光时域分析(BOTDA)的海底电缆(海缆)振动信号监测模拟实验系统,通过实验获得了锚砸、冲刷、摩擦3种工况下的海缆振动信号.针对振动信号含有大量噪声,提出TSA-VMD-MPE降噪方法.利用被囊群算法(Tunicate Swarm Algorithm,TSA)优化变分模态分解(Variational Mode Decomposition,VMD),获取VMD分解层数与惩罚因子的最优值,对振动信号分解获得本征模态函数(Intrinsic Mode Functions,IMF)分量;利用IMF与原始信号的相关性及IMF的方差贡献率联合来确定IMF的多尺度排列熵(Multi-Scale Permutation Entropy,MPE)阈值,对振动实验信号进行降噪.实验结果表明:所提降噪算法使3种海缆振动信号信噪比平均提高了12.0296 dB;将提出的MPE阈值方法应用于EEMD与CEEMD算法也获得了良好的降噪效果. 相似文献
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Kok-Meng Lee Debao Zhou 《Mechatronics, IEEE/ASME Transactions on》2004,9(3):499-507
The need for simultaneous measurement of multiple degree-of-freedom (DOF) motions can be found in numerous applications such as robotic assembly, precision machining, optical tracking, wrist actuators, and active joysticks. Conventional single-axis encoders, though capable of providing high-resolution (linear or angular) measurements, rely on mechanical linkages (that often introduce frictions, backlashes, and singularities) to constrain the device so that the three-DOF (3-DOF) motion can be deduced from the individual orthogonal measurements. We present here a noncontact optical sensor for 3-DOF planar and spherical orientation measurements. We begin with the operational principle of a microscopic-surface-based optical sensor. The design concept and theory of a dual-sensor system capable of measuring 3-DOF planar and spherical motions in real time are then presented. Along with a detailed analysis, the concept feasibility of two prototype 3-DOF dual-sensor systems for measuring the instantaneous center of rotation and the angular displacement of a moving surface is demonstrated experimentally. It is expected that the analysis will serve as a basis for optimizing key design parameters that could significantly influence the sensor performance. 相似文献
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星间光通信中振动是影响系统性能的重要因素,即使其中一个卫星的瞄准系统的很小幅度的振动也可以引起整个网络的性能急剧恶化。分析了直接检测脉位调制(PPM)下振动对网络性能的影响。 相似文献
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星间光通信振动对系统性能的影响--直接检测PPM调制方式 总被引:1,自引:0,他引:1
星间光通信中振动是影响系统性能的重要因素,即使其中一个卫星的瞄准系统的很小幅度的振动也可以引起整个网络的性能急剧恶化。分析了直接检测脉位调制(PPM)下振动对网络性能的影响。 相似文献