A SMA-based redundant actuation locking device for rotary feed structure using self-locking principle

摘要

This paper presents a locking device which achieves in locking the rotary feed structure of a space-bome microwave radiometer during the launch stage. This locking device employs two shape memory alloy (SMA) wires as the actuating elements, and uses a self-locking structure to achieve the locking function. To improve the performance and reliability, a redundant SMA wire and a step structure are employed. To validate the proposed SMA locking device, four prototypes were fabricated and tested. The result shows that the locking device possesses the advantages of remarkable locking performances, wide operation electric current and high survival temperature. Based on the test results, the locking device has a great potential for the application of space rotary structures.