高精度剪切梁式称重传感器弹性体的设计和计算

介绍了高精度剪切梁式称重传感器的工作原理和特点,并对其弹性体的设计和计算做了详细介绍。     

高精确度双圆弧边十字梁式电阻应变称重传感器

介绍了高精确度双圆弧边十字梁式电阻应变称重传感器弹性体的结构,从理论上进行了力学分析,推导了设计公式,提供了典型测试数据。     

平行梁式传感器抗偏载能力的研究

通过对平行梁式称重传感器弹性体的受力分析和实验,对平行梁式传感器抗偏载能力进行研究,指出了造成偏载误差的主要原因,并提出改进措施。     

平行梁式电容传感器极板耦合角位移计算和分析

为了解决平行梁式电容称重传感器极板耦合角位移带来的输出电容值与输入载荷之间的非线性问题,运用力法对平行梁式弹性体超静定结构进行了计算分析,得出了与上下极板夹角关联的主要结构参数,通过内力对极板角度进行了解析,并在有限元软件中验证了计算的正确性。此结果为平行梁通过结构参数设计优化耦合角位移提供了理论方法,并根据非平行板电容计算公式,构建了更加精确的载荷与电容的数学模型,为传感器输出输入特性曲线的拟合提供了依据。     

平行梁式电容传感器力学性能的仿真与分析

针对S型平行梁式电容称重传感器参数结构设计问题,运用有限元软件ANSYS Workbench对平行梁式弹性体结构进行参数化模拟仿真,基于二次多项式曲面拟合建立其结构力学性能与主要结构参数的函数关系,并通过算例分析验证了拟合公式的有效性。研究表明,拟合公式对复杂仿真计算后的结果有很好的近似,能更好的反应实际情况,公式结构更加简洁,具有较快的收敛速度、较高的精度和较好的推广能力,有利于准确实现平行梁式电容称重传感器结构参数设计。     

一体化小桥式称重传感器的设计

电子称量系统在各个称量领域的应用极为广泛,而桥式称重传感器是电子称量系统的核心元器件。一体化小桥式称重传感器是将底座与弹性体合为一体来大大缩小传感器的几何形体,并将传感器的自重大幅度降低的一种设计方法。这样更便于电子称量系统的安装和维护,缩短电子称量系统的安装和维护周期。     

制造技术在称重传感器研制,生产中的作用及其发展趋势

重点介绍了LY12铝合金弹性体的热处理及时效技术、机械加工技术和冷热加工残余应力的降低与释放技术.论述了制造技术在称重传感器研制、生产中的作用,提出了应加强对称重传感器制造技术、关键工艺的机理与规律的研究.探讨了称重传感器制造技术的发展趋势.     

一种剪切式测力传感器

一种剪切式测力传感器，它包括具有剪切筋及承载构件的弹性体，围绕承载构件在弹性体中设有数个与弹性体一体化构造的盲孔，盲孔之间的孔壁构成上述剪切筋。本实用新型的盲孔壁构成剪切筋，盲孔与弹性体一体化构造，称量准确、可靠、稳定、使用寿命长，不存在受到焊接质量及工艺影响的问题，并且采用盲孔结构还可减小传感器的体积。     

剪切梁式S型称重传感器力学分析

针对剪切梁式S型称重传感器理论分析文献较少,故障分析以及结构优化缺乏完善理论依据的现状,将OCS-XZ-10T型吊秤为原型,对其关键结构的受力情况进行了系统的分析研究.首先,明确了剪切梁式S型称重传感器的薄弱位置和强度校核方法,代入参数计算其安全系数为4.23,满足“电子吊秤最大称量300％的过载安全系数”的要求;其次...     

双平行梁荷重传感器弹性体的最优化设计

本文论述高精度、小量程传感器常用的双平行梁式弹性体的最优化设计为法.介绍的灵敏度为目标函数,线性度强度、几何条件以及其他附加要求为约束的数学模型的建立方法,改进的最优化方法的原理以及满足各种约束条件的优化计算结果。优化计算和用计算自动寻优,大大的提高了设计效率,而且获得了理想的设计方案.     

板弹簧用作称重弹性体时的迟滞与补偿

采用车辆板弹簧作为称重传感器的弹性体检测车辆载荷时,板弹簧的迟滞严重影响了载荷检测的精度。以一种卡车的后车桥板弹簧为例,介绍采用单片机对车辆板弹簧迟滞现象进行补偿的方法。这种方法简单可行,试验结果表明:补偿后,迟滞对称重结果的影响可减小为原来的20%,提高了这种称重装置的检测精度和实用性。     

双平行梁谷物流量传感器振动噪声消除方法

为消除振动噪声对谷物流量传感器的影响,设计了双平行梁结构的冲量式流量传感器并搭建了相应的流量传感器试验台,通过实时测量试验台的粮箱质量为流量传感器标定提供实际流量数据。分别提取了参考平行梁和测量平行梁输出信号中的谷物冲击谐波信号,然后以处理后的参考平行梁信号来自适应对消测量平行梁信号中的机身振动噪声。试验结果表明,在试验台处于最大振动条件下,流量传感器最大相对误差小于1.6%,显示了振动噪声消除方法的有效性。     

安装对车载秤专用传感器性能的影响

试验证实 ,传感器与底座的接触面状况及紧固螺丝的预紧力的大小会引起传感器滞后变化 ,以详实的数据说明了安装对该传感器使用性能的影响     

The influence on hysteresis from the ending pinning design of GMR free layer

With the discovery of Giant Magneto Resistance (GMR), the spin valve GMR sensor based on the effect gets developed rapidly in all areas. However, there is always error in measuring result of spin valve GMR sensor because of hysteresis, which will limit widespread use of the sensor. Started with sensor structure, the paper puts coercivity as an important index to evaluate hysteresis characteristics. And a new method is proposed to reduce the hysteresis, namely with anti-ferromagnetic materials to pin the end of free layer. On this basis, the influence of pinning shape and pinning angle on hysteresis is focused research by theory and simulation at the same time. The results show that with the constant pinned area, the hysteresis is irrelevant with pinning shape, and different pinning angle will induce the change of hysteresis characteristic. The investigation will establish a theoretical basis for designing a low coercivity spin valve GMR sensor.     

动态轴向载荷下谐振梁振动响应分析

在航空航天飞行控制中,为实现关键参数的高精度高动态测量,急需发展具有快速响应特性的谐振式传感器。谐振式传感器本质上是输入与谐振器振动状态之间的映射。这种映射一般通过跟随输入的轴向载荷调制谐振梁的固有频率实现。高动态应用中的核心问题是动态轴向载荷下谐振梁的振动响应。利用基本的微元力学平衡关系建立了动态轴向力作用下谐振梁振动行为的数学模型。此模型比Mathieu方程的适用面更广,在一般假设下更难以进行解析或数值求解。为此引入了等效电路方法进行模型求解。通过对等效电路的仿真,得到了谐振梁在多种典型动态载荷下的振动响应。动态轴向载荷对于谐振梁的作用具有强烈的非线性和独特的规律,值得进一步深入研究探讨。     

Determinants of load carrying ability

The aim of this paper is to review the literature in respect of the main determinants of a person's load carrying ability. Possible determinants of load carriage ability include age, anthropometry, aerobic and anaerobic power, muscle strength, body composition and gender; other relevant factors are the subjective effects perceived during load carriage, the dimensions and placement of the load, biomechanical factors, nature of the terrain and the gradient, the effect of climate and protective clothing. It is important to distinguish between the maximum load carrying capacity and load carriage ability which enables the individual to retain the capability to perform other tasks - eg, observation and navigation, or industrial tasks. The soldier has been used as the worst case example of extremely heavy loads having to be carried for long durations; civilian examples are usually less demanding except in the case of mountaineers, explorers and some occupations. The energy cost of walking with loads has been found to depend primarily upon the walking speed, body weight and load weight, together with terrain factors such as gradient and surface type; equations exist which allow the prediction of energy expenditures from these variables, and they can provide a valuable guide in assessing the physical severity of proposed tasks involving load carriage. Other factors such as the degree of environmental heat stress and protective clothing worn would have to be taken into account, but the level of energy expenditure (or heat production) assumes central importance as it is related to physical exhaustion, heat exhaustion and also less directly to the efficiency of performance of occupational task involving load carriage. This review confirms that there is no obvious definition of a maximal load, because of the widely varying circumstances which might apply, but for healthy young males there appears to be some consensus for the traditional rule of thumb of one-third body weight, or 24 kg on an assumed mean body weight of 72 kg, or in terms of relative work load equivalent to one-third of the VO(2) max for a working day. Renbourn (1954c) considered that the load carried by the soldier will probably always be a compromise between what is physiologically sound and what is operationally essential. Load carriage in industrial and other civilian areas will also involve a similar compromise and may in some circumstances lead to important implications for health and safety.     

一种无源无线SAW压力传感器结构设计

根据无源无线SAW压力传感器的敏感特点,提出了一种具有较高灵敏度的压力传感器结构设计.传感器的受力敏感部分采用简支梁结构,通过分析找到梁的最大应变点,在梁的上下两侧最大应变区域中心对称分布了两个相同的单端口SAW谐振器.由两个SAW谐振器组成差动式测量结构,具有较高的灵敏度,并减少了温度对测量结果的影响,对迟滞效应带来的误差有一定的补偿作用.     

Validation of flexible multibody dynamics beam formulations using benchmark problems

As the need to model flexibility arose in multibody dynamics, the floating frame of reference formulation was developed, but this approach can yield inaccurate results when elastic displacements becomes large. While the use of three-dimensional finite element formulations overcomes this problem, the associated computational cost is overwhelming. Consequently, beam models, which are one-dimensional approximations of three-dimensional elasticity, have become the workhorse of many flexible multibody dynamics codes. Numerous beam formulations have been proposed, such as the geometrically exact beam formulation or the absolute nodal coordinate formulation, to name just two. New solution strategies have been investigated as well, including the intrinsic beam formulation or the DAE approach. This paper provides a systematic comparison of these various approaches, which will be assessed by comparing their predictions for four benchmark problems. The first problem is the Princeton beam experiment, a study of the static large displacement and rotation behavior of a simple cantilevered beam under a gravity tip load. The second problem, the four-bar mechanism, focuses on a flexible mechanism involving beams and revolute joints. The third problem investigates the behavior of a beam bent in its plane of greatest flexural rigidity, resulting in lateral buckling when a critical value of the transverse load is reached. The last problem investigates the dynamic stability of a rotating shaft. The predictions of eight independent codes are compared for these four benchmark problems and are found to be in close agreement with each other and with experimental measurements, when available.     

基于滞环SVPWM控制的航空电子负载研究

本文提出了航空交流电子负载的拓扑结构和总体控制策略,研究了滞环空间电压矢量控制在电子负载中的实现方法。该方法将滞环与SVPWM控制相结合,通过空间电压矢量的适时切换,使电流误差被限制在一个给定的滞环内,从而获得对电流的高品质控制。该方案提高了电压利用率,同时能够实现对电流的精确跟踪控制,仿真结果表明其动态性能良好,所设计的电子负载符合航空电源测试标准。