The request of even more stringent restrictions, regarding efficiency and environmental impact of industrial components, determines an optimized use of primary energy but also entails the design of more lightweight, smart and flexible devices, able to adapt their operation as a function of several different inputs. In this framework, the use of a fascinating class of metallic materials, called Shape Memory Alloys (SMAs), could represent a valid support for the designers. The capability of these materials to react to an external stimulus, without continuing to supply energy to external actuators, represents, especially in the aerospace engineering field, a technological breakthrough. The present paper reports the basic ideas and summarizes the important aspects related to the development of SMA-based actuators in relation to the present state of the art. A case study of morphing blades, equipped with embedded SMA strips, for an automotive cooling fan is reported. Finally, some hints, regarding the design process of SMA-based actuators, are proposed.

中文翻译：

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基于 SMA 的变形执行器的设计策略：应用于引人入胜的案例研究的最新技术和常见实践

在工业组件的效率和环境影响方面要求更严格的限制，这决定了一次能源的优化使用，但也需要设计更轻巧、智能和灵活的设备，能够根据几种不同的输入来调整其操作. 在这个框架中，使用一种称为形状记忆合金 (SMA) 的迷人金属材料可以代表对设计师的有效支持。这些材料能够对外部刺激做出反应，而无需继续为外部执行器提供能量，这代表了一项技术突破，尤其是在航空航天工程领域。本文报告了基本思想并总结了与基于 SMA 的执行器开发相关的重要方面，以及与当前技术水平相关的内容。报告了用于汽车冷却风扇的带有嵌入式 SMA 条带的变形叶片的案例研究。最后，提出了一些关于基于 SMA 的执行器设计过程的提示。