齿轮轴校直理论及实验研究

基于弹塑性理论，在研究齿轮轴结构的基础上，提出了确定齿轮轴校直行程的计算方法，经实验验证该计算方法是有效的。     

二重完成超大直径齿轮轴渗碳淬火

日前，中国第二重型机械集团公司（中国二重）顺利完成江苏联峰能源80万t大棒开坯机项目中下齿轮轴渗碳淬火工序。据了解，该轴为中国二重迄今为止直径最大的渗碳淬火齿轮轴。由于该件齿轮轴长度达到3911mm，已接近该公司井式渗碳炉尺寸，用常规方法淬火不行。对此，在技术准备时，中国二重工艺员设计了专用起吊吊耳，以保证淬火起吊安全。     

两种热处理方法对减速机渗碳齿轮轴的影响

对减速机渗碳齿轮轴、通常采用渗碳油淬，表淬再低温回火的热处理方法，而对机械性能有特殊要求的渗碳齿轮轴如何处理较为合理呢？本文采用了渗碳油淬后再加一道高温回火的处理方法，通过这两种热处理方法的分析与比较，以期寻找一种最佳工艺方法，满足设计者的要求。     

NX环境下齿轮轴的模态分析

针对齿轮轴的结构特点,运用有限元方法建立了齿轮轴的有限元模型,进行了模态分析,给出了齿轮轴的前10阶的固有频率和振型,并对频率和位移响应态进行了分析,指出位移变形最大发生部位,为齿轮轴的优化设计提出建议与改进措施。     

齿轮轴多目标优化分析

针对齿轮轴的共振问题,采用有限元方法对齿轮轴进行分析,得到其低阶固有频率及其振型。以齿轮轴第一阶频率和第二阶频率最大同时齿轮轴质量最小为目标函数,基于Isight集成优化平台,分别采用AMGA算法、NCGA算法和NSGA-Ⅱ算法对齿轮轴的轴颈直径进行优化分析,优化之后齿轮轴的第一阶、第二阶的固有频率分别增大了6.16%和6.13%,都处于其啮合激励频率的范围之外,并且其质量较优化之前也有所降低,因此将会有效避免齿轮轴发生共振。     

重载无空刀槽人字齿轮轴的制造加工工艺探讨

以临钢中板厂Ф750中板轧机人字齿轮轴加工为例，叙述了无空刀槽中硬齿面人字齿轮轴，拟定加工工艺时值得注意的一些问题，用以提高齿轮轴使用寿命和达到其技术要求。     

含有裂纹的齿轮轴动力特性分析与模拟

将裂纹梁理论应用于齿轮轴的动力学研究当中，以轴开放裂纹作为研究对象，对齿轮轴出现裂纹后的动力特性进行了分析模拟，并对裂纹位置和裂纹尺寸等对轴特性的影响进行了深入探讨，指出裂纹发生位置对齿轮轴的振型有着直接的影响，在裂纹发生处振型发生突变，而裂纹尺寸对轴的振型和固有频率都有影响，当出现裂纹后齿轮轴的固有频率发生下降，越是大尺寸的裂纹，轴固有频率越是下落显著。这对齿轮轴的损伤监测和诊断具有重要价值。     

少齿数齿轮的弯扭变形计算

齿数少于7的齿轮轴刚度较差,设计和传动中需要考虑其较大的弯曲和扭转变形。为获取少齿数齿轮轴弯扭变形的计算方法,建立了具有切向和径向变位的小齿轮的端面齿廓模型,得到了齿轮轴弯扭变形当量直径的计算公式。考虑到大螺旋角对齿轮轴弯扭变形的影响,借助有限元计算分析,分别得到了螺旋角对齿轮轴的弯曲和扭转扭变形影响系数。以齿轮轴当量直径、螺旋角影响系数为主要参数,实现了一定精度的少齿数齿轮轴弯扭变形的简化计算。     

汽车变速箱齿轮轴的模态优化分析

汽车变速箱是齿轮、齿轮轴、轴承和箱体等组成的机械结构,在内部和外部激励作用下将产生机械振动。当激励的频率在结构固有频率附近时,将使箱体产生振动。齿轮轴是变速箱的关键传动部件,为了提高某汽车变速箱输入齿轮轴的前六阶固有频率,应用参数化建模方法和CAE软件对齿轮轴进行模态分析,获得其固有频率和振型,然后基于集成优化平台,采用自适应模拟退火算法对齿轮轴的轴颈直径进行优化设计。最终提高了齿轮轴的低阶固有频率,避免了发生共振,减少了齿轮轴的振动和噪声,并实现了设计优化过程的自动化。     

精密RV减速器输入齿轮轴振动分析

精密RV减速器输入齿轮轴是整机实现两级减速的重要零部件.输入齿轮轴的啮合传动状态直接决定精密RV减速器的传动性能,其模态振动特性对整机动态特性有重要影响.以RV-80E减速器为研究对象,对啮合状态下的精密RV减速器输入齿轮轴进行振动分析.在分析中,对精密RV减速器进行三维建模,通过有限元方法对输入齿轮轴在自由、轴承约束、啮合工作三种状态下的模态特性分别进行仿真,得到输入齿轮轴在三种状态下的频率分布及振动模态.仿真结果表明,输入齿轮轴的变形主要发生在齿啮合处.在啮合状态下,齿轮系啮合引起的输入齿轮轴头部变形最大,输入齿轮轴的固有频率与其它两种状态相比变化明显.     

Quantum Cooperative Robotics and Autonomy

The intersection of Quantum Technologies and Robotics Autonomy is explored in the present paper.The two areas are brought together in establishing an interdisci...     

考虑进油孔有限长滑动轴承油膜力的近似解析解

针对具有进油孔的有限长滑动轴承油膜力求解问题,采用变分原理和分离变量法,求得了有限长滑动轴承油膜压力分布的近似解析表达式。将油膜压力分布的近似解析表达式在油膜存在区域上进行积分,即得到了油膜力。将提出的计算有限长滑动轴承油膜力方法与无限长轴承模型、有限元方法的计算结果进行了比较,发现了提出的方法与有限元方法的计算结果很接近。最后,研究了进油孔位置和进油压力对油膜存在区域、油膜力等的影响,研究结果表明进油孔位置和进油压力对油膜存在区域和油膜力有较大的影响。     

三绕组变压器的双绕组等效建模及在Matpower中的应用

针对实际电网存在着大量的三绕组变压器,但国际上一些著名商业软件,如BPA仿真软件、Matpower这一权威潮流计算开源软件,均只提供双绕组变压器模型,限制了其在具有三绕组变压器的电力系统中的应用的问题,潮流计算是自主开发的电力系统各种应用软件的核心模块,因此依托国际权威开源程序进行二次开发,是一种较好的选择。对Matpower要求的数据格式进行了归纳,对变压器的一般的等值电路及带理想变压器的等值电路和带标幺值的等值电路进行了分析研究,提出了三绕组变压器转换为双绕组等效模型的建模方法,使得原先只适应双绕组变压器的潮流计算软件可以适用于三绕组变压器电网的潮流计算;最后以Matpower软件为例进行了案例计算,并用PSASP仿真软件进行对比验证。研究结果证明,所提出的建模方法是有效的。     

On the Relation of Load to Average Gap in the Contact Between Surfaces with Longitudinal Roughness

A computer simulation model for the contact between longitudinally-oriented rough surfaces has been formulated. This model closely duplicates the actual surf ace contact deformation behavior by taking into account the elastic interactions between the asperities. There were no assumptions made about the shapes, or any deformation behavior of the asperities, except for their obeying the laws of elasticity. The plastic deformations on the high asperity peaks were taken into account by setting a ceiling on their contact pressures at the material hardness value. The simulations used real surface profiles which were digitized from unworn circumferentially ground steel surfaces. Each pair of these profiles was mathematically combined to form an equivalent rough profile pressing against an infinitely rigid flat and having the appropriately adjusted elastic modulus. A total of 28 different pairs of profiles were used in the simulations. Each contacting pair was subjected to 30 different load levels and the local contact pressures and deformations were calculated. The contact simulations yielded some important mathematical relationships between parameters, such as the real area of contact, average gap, and average asperity load through statistical curve fitting. Two analytical functions were generated to relate the average load to average gap and the real area of contact to load.     

电站锅炉模糊风险评价方法研究与应用

针对电站锅炉风险等级评价问题,将模糊综合评价技术应用到电站锅炉风险等级评价中。开展了电站锅炉失效影响因素及模糊评价因素的重要程度分析,建立了一套科学合理适于在线评价的电站锅炉风险评价体系,提出了模糊综合评价技术与改进的模糊层次分析法相结合的模糊风险评价方法,利用改进的模糊层次分析法计算了指标体系中各层指标权重。对某一台电站锅炉的实际运行工况影响子因素进行了模糊风险评价,采用模糊合成算子进行模糊综合运算得到电了站锅炉运行工况影响子因素的评价向量。研究结果表明:电站锅炉的运行工况影响子因素的风险评价等级为第6级,失效可能性等级为小,该电站锅炉运行工况良好。     

基于多目标非支配解提取法的电力系统无功优化

针对传统的电力系统多目标粒子群优化算法采用权重系数法将多目标转化为单目标,从而忽视了各目标函数间的竞争关系这一问题,提出将非支配解提取法运用到电力系统多目标无功优化中,并设定了一套提取规则,以电力系统中的有功网损、电压偏差和电压稳定裕度为目标,使目标在充分竞争的情况下得出Pareto最优解,利用IEEE-14节点系统对多目标非支配解提取法的电力系统无功优化进行了仿真测试。研究结果表明,该算法一次运行可以得出多组非支配解,既有偏向单个目标的解也有兼顾所有目标的解,克服了权重系数法的盲目性和单一性,可使电力决策者根据实际问题选择最优解,具有较好的灵活性与多样性。     

交通荷载作用下桥梁结构参数识别方法

应用动力节点加载法,将作用在桥梁上的交通荷载转化为等效节点荷载,再用两步构造法识别结构物理参数.第1步,用Newmark-β方法变换结构运动方程,并用结构的加速度响应求得变换空间内的位移、速度和加速度响应;第2步,基于最小二乘原理,构造出变换空间内求解结构参数的递推式,进行结构物理参数识别.数值模拟结果表明,在交通荷载作用下,该方法能够快速、准确地进行桥梁结构参数识别.     

RLS and LMS blind adaptive multi-user detection method and comparison in acoustic communication

RLS and LMS blind adaptive multi-user detection algorithm and multi-user detector was proposed to solve the problem of multi-user signal detection problem encountered in underwater acoustic communication networks.In simulation analysis,RLS and the LMS blind adaptive multi-user detector were designed and tested for synchronous and asynchronous multi-user communication process.The results of SIR comparison and MMSE comparison show that,both of the two methods can realize blind adaptive detection when any user change in multi-user communication,during this process,the training communication sequences are not needed.The RLS algorithm has about 5 dB higher in SIR compared with LMS algorithm,and the convergence velocity of RLS algorithm is also higher than LMS algorithm when the communication users change.RLS algorithm has better ability in multi-user detection than that of LMS algorithm,and it has great attraction and guiding significance for solving the problem of multiple access interference(MAI) in multi-user communication.     

Robust Impedance Control of Robots Using an Adaptive Interaction Force Observer

For robot interaction control,the interaction force between the robot and the manipulated object or environment should be monitored.Impedance control is a type ...     

Research on key techniques of expendable conductivity temperature depth measuring system

This paper analysis the developing of expendable conductivity temperature depth measuring system(XCTD)and introduce its principle of measuring about temperature,salinity and depth of ocean.Some key techniques are put forward.According to the real needs of XCTD,conductivity sensor with high sensitivity is designed by principle of electromagnetic induce,the ocean conductivity from induced electromotive force has been calculated.Adding temperature correction circuit would help to reduce error of conductivity measurement because of sharply changing temperature.Advanced temperature measuring circuit of high precision and the constant current source is used to weaken effect of self-heating of resistance and fluctuation of the source.On respect of remote data transmission,LVDS is a good choice for the purpose of guarantee the quality of data transmitted and the transmission distance is reaching to thousand meters in the seawater.Modular programming method is also brought into this research aimed at improve the stability,reliability and maintainability of the whole measuring system.In February,2015,the trials in South China Sea demonstrate that the developed XCTD realize effective measurement at a speed of 6 knots and detection depth at 800 m.The consistency coefficient of the acquired data is greater than 0.99 and the success rate of probe launching is above 90%.