共查询到20条相似文献,搜索用时 171 毫秒
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对五轴加工仿真中刀具扫掠体的计算方法进行了研究。根据刀位文件,构建了运动坐标系。给出一个通用的刀具模型,方便了用户定义刀具和编辑刀具。分析了典型的球头刀临界线的计算方法,该方法独立于具体的机床结构。重点研究了国内外常用求解方法后,设计并实现了一种快速的分解表示方法,采用这种方法近似构造扫掠体。该方法已经应用到由ACIS+HOOPS组件技术开发的五轴数控仿真系统中,实验证明这种方法可以很好的满足加工精度和时间要求。 相似文献
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飞行模拟器作为良好的地面模拟仿真设备,具有许多优良的特性。借助飞行模拟器可以有效地进行飞行特性研究和飞行训练。在设计制造时,需要对模拟器进行评估以满足研究和训练要求,评估方法的研究已成为重点内容。综述了逼真度评估方法的研究现状,重点概述了结构模型方法和控制论2种方法。阐明了由于存在多种评估方法和标准,评估效果很难比较。分析了客观评估方法所面临的困难,展望了未来的研究方向。 相似文献
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基于有限元方法的动平衡机的设计 总被引:1,自引:0,他引:1
首先基于有限元建立了转子的动力学模型,然后给出了动平衡机硬支承的设计方法,同时利用有限元方法计算得出了系统的固有频率和各机构间的阻尼系数;然后分析了现有标定方法的特点,提出了优化的标定方法,该方法优于现有标定方法;最后根据处理后振动信号的特点,结合已有数字信号处理算法,提出一种更精确不平衡量提取方法,以提高动平衡机的灵敏度和精度。实验证明,该系统具有高效、高精和稳定的特点。 相似文献
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赵冰 《稀有金属材料与工程》2016,45(8):2189-2200
介绍了国内外在金属三维点阵结构制备方法的研究进展,及不同制备方法的特点,并进行了对比分析。提出了一种超塑成形/扩散连接工艺(SPF/DB)来制备金属三维点阵结构的方法,这种方法将点阵夹层结构看作三层或多层夹层结构,采用SPF/DB工艺方法在一个热循环中制备了金字塔型、四面体型、X型等典型的金属三维点阵结构,验证了工艺的可行性,为金属三维点阵结构的制备开辟了一条新的技术路径。对比分析了增材制造方法、塑性成形方法、SPF/DB等制备方法的特点和优点,对金属点阵结构技术的发展进行了展望。 相似文献
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针对齿轮泵在设计过程难以有效估算其寿命的问题,提出了一种通过增加油液介质污染度的齿轮泵加速寿命试验方法。该方法分析了影响齿轮泵寿命的失效原因,并选择介质污染度作为加速寿命的应力选择;给出了齿轮泵的磨损加速寿命试验方法;建立加速寿命模型并以试验数据为基础,利用统计分析方法得出了齿轮泵的寿命及可靠性指标计算方法。结果表明:该方法是可行的,能有效缩短试验周期,节约试验成本,为齿轮泵寿命估算提供了参考。 相似文献
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The anodic dissolution of copper in NaCl solutions with the application of an external magnetic field of 450 mT is studied by digital holography. The effects of the field on the basic electrochemical processes are visualized through reconstructed phase maps, which enable direct observation of the magnetohydrodynamic flow during the electrochemical mass transport. The magnetic field affects the anodic dissolution of copper in chloride media in two ways: restraining the formation of the CuCl salt layer, increasing the mass transport rate. The presentation of dynamic phase maps through the video enhances the power of digital holography in investigating electrochemical processes. 相似文献
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We present an experimental approach to rapidly measure the 3D shape of a micro deep drawing part, which is based on a digital
holographic contouring. Inline quality control in a micro deep drawing process requires a rapid and nondestructive measurement
technique, which is the significant advantage of digital holography. The surface structure of the investigated object is dominated
by the properties of the drawing process. Therefore, we investigate the statistical properties of the light scattered from
the surface and show that digital holography is applicable in this case. Finally, we present experimental results which proof
the big potential of digital holography in regards to the inspection of micro parts. It is shown that the field of depth can
be considerably enhanced by combining several reconstructions associated with different observation planes from a set of two
recorded holograms. 相似文献
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The effects of chloride and thiosulfate ions on localized corrosion of alloy 800 are investigated through dynamical observation of the change in phase image of the diffusion layer during passive film breakdown using digital holography. The results indicate that solution chemistry has a significant effect on film breakdown and diffusion layer. The phase distribution changes at different applied potentials show that in the process of film breakdown, dissolution of metal ions from pitting is not remarkable in chloride-only solution, whereas dissolution of metal ions is significantly high in thiosulfate and chloride solution. Thiosulfate has a combined effect with chloride ions in passive film degradation. 相似文献
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针对永磁直线同步伺服电机(PMLSM)直接驱动数控机床伺服系统,提出了一种基于摩擦力和扰动补偿的零相位误差跟踪控制策略.以解决摩擦力和扰动对系统性能的影响.零相位误差跟踪控制器保证了快速性,使系统实现准确跟踪;而补偿制器克服了摩擦和扰动等不确定性影响,保证了系统具有较强的鲁棒性和定位精度.仿真结果表明,该种控制方案较好地改善数控机床进给的定位精度和跟踪性能. 相似文献
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《Acta Materialia》2002,50(8):2173-2184
Magnetic domain structures in recently developed Co–Ni–Al ferromagnetic shape memory alloys were examined by Lorentz microscopy and electron holography, and relations of the martensite variants (crystallographic domains) and the magnetic domains were discussed. Direct observations of the magnetic domain walls by Lorentz microscopy and the magnetic lines of force by electron holography revealed that each martensite variant was divided into fine magnetic domains under a low magnetic field, e.g. about 0.2 mT. Although an applied magnetic field of about 0.4 T made each variant a large single magnetic domain, a similar configuration of multiple magnetic domains to the previous one appeared when the applied field was removed. In situ Lorentz microscopy studies have demonstrated that magnetic domain structures are sensitive to the crystal structure and/or microstructure in Co–Ni–Al alloys, i.e. a magnetic domain structure favorable to the parent phase is not inherited to the parent phase, but a distinct domain structure is observed in the martensitic phase. 相似文献
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目的 验证一种喷涂层下基体疲劳裂纹红外热成像识别方法。方法 综合采用理论分析、数值模拟和试验研究相结合的方法,基于热波传导理论分析超声波激励下基体裂纹产生的热波与喷涂层裂纹产生的同频率热波,在向涂层表面传播过程中发生的叠加干涉效应,以及由此导致的表面热波相位偏移现象。采用数值模拟手段研究涂层裂纹热波与基体裂纹热波之间的叠加干涉规律,开展喷涂层下基体疲劳裂纹的超声红外热成像检测试验验证该方法的有效性。结果 受到脉冲超声波激励后,基体裂纹与涂层裂纹产生的热波向表面传导过程中会发生叠加干涉效应,并导致涂层表面热波相位发生偏移,低频热波相位偏移现象比高频热波更加明显。结论 采用涂层表面热波相位特征识别涂层下基体中的疲劳裂纹是一种可行且高效的方法。 相似文献
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