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利用形状记忆合金(SMA)的记忆特性设计了一种低转速,可连续旋转的电机;利用Liang-Rog-er本构模型进行了SMA-弹簧的旋转位移驱动器的设计以及电机扭矩和转速的设计;完成了SMA电机的机械结构设计;完成了控制规律设计;进行了性能试验.研究结果表明,在试验温度27℃下,用6 V恒压电源驱动的SMA电机实现了连续旋转,转速为0.03 rad/min.SMA电机转速低,扭矩大,功率密度高,可连续旋转,有很大的工程应用潜力. 相似文献
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JIANG Da-qiang CUI Li-shan* ZHENG Yan-jun JIANG Xiao-hua Department of Materials Science Engineering China University of Petroleum Beijing China 《中国航空学报》2006,19(Z1)
A TiNi-alloy is solution-treated in a vacuum furnace of 6.7×10-3 Pa at 1 223 K for 3.6 ks, and then aged at 773 K for 1.8 ks. The differential scanning calorimetry (DSC) measurements show that after the heat-treatment, takes place a two-step reverse Martensitic transformation, from which results the two-stage recovery strain in a prestrained Martensitic TiNi-alloy wire during heating. The Vickers microhardness indentation test in cross-sectional areas of the TiNi-alloy wire indicates the compositional heterogeneity between its sur-face layers and its inside. The fact that the sizes of the indentation in surface layers smaller than those in the inside bears witness to the existence of slightly harder surface layers. It is believed that these phenomena are related to the compositional fluctuation caused by the evaporation and oxidization of Ti-element during the solution-treatment and heterogeneity formed during the subsequent aging treat-ment. 相似文献
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针对传统跟踪与数据中继卫星系统(TDRSS)中S波段多址(SMA)业务直接序列扩频码分多址(DS-CDMA)的缺点,提出采用多载波码分多址(MC-CDMA)进行替代的调制解调方案,对其系统结构和在TDRSS中应用需解决的关键技术问题进行了分析。MC-CDMA具有数据传输速率和频带利用率高,发送和接收设备简单等优点,在载人航天通信中具有十分重要的应用价值。 相似文献
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根据NiTi丝的拉伸实验结果,基于滞后元方法,建立了拉伸状态下应力-应变曲线的唯象物理模型,并进行了数值模拟。研究结果表明(1)SMA丝在马氏体相变,特别是R相变时出现一系列物理、力学性质的异常变化,其应力-应变关系呈现高度非线性;(2)在NiTi丝断裂之前没有明显的屈服现象;(3)物理模型的数值模拟结果与实验结果吻合较好。 相似文献
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Patrick Harkness Malcolm McRobb Paul Lützkendorf Ross Milligan Andrew Feeney Craig Clark 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2014
A prototype CubeSat module to deploy a gossamer aerobrake, using strain stored in tape-springs, at end-of-life is described. A novel hub geometry to reduce bending shock at end-of-deployment while simultaneously permitting radial, as opposed to tangential, deployment is proposed. The rpm of the hub is measured under various deployment conditions to verify that the system offers highly-repeatable performance, while high-speed photography is used to characterise the behaviour of the tape-spring during unspooling and contrast it to the behaviour of a traditional tangential-deployment system. Secondly the folding pattern of the membrane, which takes advantage of the symmetrical deployment offered by the petal hub, is developed and the unfolding mechanism is verified by numerical and experimental analysis. Finally, the release of the stored strain is considered and a novel burn-though device is designed and prototyped to meet this requirement. 相似文献
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利用形状记忆合金(shape memory alloy,SMA)独特的超弹性效应,提出一种利用形状记忆合金提高复合材料结构抗低速冲击性能的方法.基于形状记忆合金的分段化线性简化模型,利用ABAQUS有限元软件提供的VUMAT子程序编制了SMA合金超弹性本构关系并将其引入到复合材料层板低速冲击模型,提出了含SMA复合材料低速冲击数值模拟方法.研究形状记忆合金利用迟滞阻尼特性吸收部分形变能量并加以释放的过程,探讨SMA纤维对复合材料层板抗冲击性能的增强规律.结果表明,随着SMA体积分数的提高,复合材料层板的冲击应力峰值和挠度会下降,但在低SMA体积分数(<10%)情况下,对挠度的改善作用不明显;同时随着SMA体积分数增加,单位体积SMA的冲击能量吸收率会降低,在SMA体积分数为5%~10%时,SMA纤维具有最高的能量吸收率.得出了SMA纤维具有改善复合材料抗冲击性能的作用的结论. 相似文献