title: Development of a novel shape memory alloy-actuated resettable locking device for magnetic bearing reaction wheel.
abstract: The current investigation proposes a shape memory alloy (SMA)-actuated resettable locking device for magnetic bearing reaction wheel. The device employed two SMA wire-based actuators to realize locking and unlocking. Dual-slope mating surfaces were used on one hand to transmit the motion between a moving part and a clamp, and on the other hand to achieve a self-locking linkage in the locking state. Moreover, geometric parameters of the two SMA wires and corresponding bias springs were also designed. Based on the proposed design scheme, four locking devices were manufactured and assembled. Performance and environmental tests were performed to verify the proposed locking device. Test results show that the locking device can protect the magnetic bearing reaction wheel from launch vibration damage, and can withstand the thermal environment in the launch and on-orbit stage. Moreover, the device can be successfully operated for 76 times, and the response time for the locking and unlocking processes under 7 V power supply is 0.9 s and 5.6 s, respectively. Considering the results obtained from these tests, we conclude that the proposed resettable locking device is an attractive alternative technology to conventional motor-driven or pyrotechnics-based technologies, and can be applied reliably in the magnetic bearing reaction wheel.
authors: School of Energy and Power Engineering, Beihang University, Beijing 100191, China.
authors: Xiaoyong
authors: X
authors: Zhang
authors: School of Energy and Power Engineering, Beihang University, Beijing 100191, China.
authors: Xiaojun
authors: X
authors: Yan
authors: Beijing Institute of Control Engineering, Beijing 100190, China.
authors: Shaowei
authors: S
authors: Zhang
authors: School of Energy and Power Engineering, Beihang University, Beijing 100191, China.
authors: Jingxu
authors: J
authors: Nie