A reusable locking and releasing mechanism for space optical payloads

一种用于空间光学载荷的可重复使用锁紧释放机构

China Academy of Space Technology(Xi'an), Xi'an 710100, China

Received: 22 September 2024

Abstract

A locking and releasing mechanism actuated with shape memory alloy (SMA) wire is proposed to meet the locking and releasing requirements of space optical payloads. This mechanism uses a kinematic chain composed of contacting rollers to transfer a high preload, and the releasing action can be triggered with a small driving force generated by SMA wire. In order to verify the proposed design scheme of the mechanism, a prototype is developed, and the locking and releasing test, high environment temperature adaptability test are carried out. The test results show that the mechanism can maintain locking stage under a preload of 15 kN, and release successfully under a DC current from 4.0 A to 6.0 A, the corresponding release time are 1.53-0.61 s. In addition, the mechanism won't release unexpectedly when the environment temperature is below 79 ℃. Based on the test results, the mechanism has the advantages of high preload-carrying capacity, low-shock, no pollution and reusability, it can be widely used as a locking-release device for space optical payloads.

摘要

针对空间光学载荷的锁紧释放需求, 提出了一种基于形状记忆合金(shape memory alloy, SMA)丝驱动的锁紧释放机构, 该机构采用滚柱对锁紧力进行多级传递, 能够承载较大的锁紧力, 通过SMA丝产生较小的驱动力即可触发解锁。为了验证该锁紧机构设计方案的可行性, 开发了机构原型样机并进行了地面锁紧解锁试验及高温环境试验。试验结果表明, 该锁紧机构可承载15 kN的锁紧力, 在4~6 A的解锁电流下可实现快速解锁, 对应解锁释放时间为1.53~0.61 s, 另外, 机构在低于79 ℃的环境温度下能够保持锁紧状态而不发生误解锁。基于设计及地面试验结果, 该机构具有承载力大、冲击小、无污染、可重复使用等优点, 可广泛应用于空间光学载荷锁紧领域。