Xiaojun Yan, Dawei Huang, Xiaoyong Zhang, Ying Liu, Qiaolong Yang
School of Energy and Power Engineering, Beihang University, Beijing 100191, China.
China Academy of Space Technology, Youyi Road, Beijing 100094, China.
Rev Sci Instrum. 2015 Dec;86(12):125005. doi: 10.1063/1.4938178.
This paper proposes a SMA (shape memory alloy) wire-based separation actuator with high-load capacity and simple structure. The novel actuator is based on a one-stage locking mechanism, which means that the separation is directly driven by the SMA wire. To release a large preload, a group of anti-friction rollers are adopted to reduce the force for triggering. In addition, two SMA wires are used redundantly to ensure a high reliability. After separation, the actuator can be reset automatically without any auxiliary tool or manual operation. Three prototypes of the separation actuator are fabricated and tested. According to the performance test results, the actuator can release a maximum preload of 40 kN. The separation time tends to decrease as the operation current increases and it can be as short as 0.5 s under a 7.5 A (the voltage is 5.8 V) current. Lifetime test indicates that the actuator has a lifetime of more than 50 cycles. The environmental tests demonstrate that the actuator can endure the typical thermal and vibration environment tests without unexpected separation or structure damage, and separate normally after these environment tests.
本文提出了一种基于形状记忆合金（SMA）丝的具有高负载能力和简单结构的分离致动器。这种新型致动器基于一级锁定机构，这意味着分离直接由SMA丝驱动。为了释放较大的预紧力，采用了一组减摩滚轮来减小触发力。此外，冗余使用两根SMA丝以确保高可靠性。分离后，致动器无需任何辅助工具或手动操作即可自动复位。制作并测试了三个分离致动器原型。根据性能测试结果，该致动器可释放的最大预紧力为40 kN。分离时间倾向于随着工作电流的增加而减少，在7.5 A（电压为5.8 V）的电流下可短至0.5 s。寿命测试表明该致动器的寿命超过50次循环。环境测试表明，该致动器能够承受典型的热和振动环境测试，不会出现意外分离或结构损坏，并且在这些环境测试后能正常分离。
