An SMA-actuated locking device for feed source structure based on self-locking principle

An SMA-actuated self-locking mechanism is proposed in this article. This mechanism works with a self-locking principle, and two SMA wires are used to realize redundantly locking and unlockingin an actuator. In order to verify the proposed design scheme, several prototypes are fabricated, and locking test, electrical performance test and high-temperature environment survival test are carried out. The test results show that the mechanism can maintain locking state even under a load of 1700 N. It can operate well under a DC current from 2.5A to 4A, the corresponding response time and power consumption are 15.8~4.2 s and 140~95 J respectively. Moreover, this mechanism can operate normally when the environment temperature is under 92℃. Based on the test results, the locking mechanism possesses the advantages of remarkable locking performance, wide operation current and high survival temperature, and has great potential for the application in space rotary structures.