Development And Experiment Of Shape Memory Alloy Rotary Lock/Release Mechanism

With the development of space technology, more and more components need tocommence in orbit. Since the weight of components and their different sensitivity toimpact the environment and therefore requires a different locking releasingdevices.Pyrotechnic devices are the earliest and most commonly locking releasemechanism used on spacecraft. However, pyrotechnic devices would have a greatimpact on unlocking when it is in motion, resulting in releasing gas with chemicalcontamination after the explosion, so it is no longer suitable for use in some spacecraft.Research on the development and application of non-pyrotechnic device has been paidmore and more attention.In this paper, using the locking release with deployable spaceantenna board wavefront as the application background, using a shape memory alloybased on smart material (SMA, Shape Memory Alloy), we developed locking releasedevice capable of carrying large、with small impact and being reusable.Firstly, we tested material properties of SMA, we got a main material performanceparameters of SMA which provides a reliable material data for the subsequent design.We propose a design program for rotary shape memory alloy locking releasemechanism, which uses class bearing rotary unlocking release mechanism, making useof SMA wires energized contraction trigger, releasing the locking force of the drive tocomplete the unlocking action. The program makes the unlocking action using rollinginstead of sliding, SMA wire is triggered by force rather than a direct unlocking force,therefore, the program has high mechanical efficiency, low energy consumptionadvantages that can better meet the onboard power requirements. Using Pro/E toestablish the overall three-dimensional model of SMA unlocking release device.Taking the locking and unlocking performance of the device into considerationrespectively, we analyzed the locking force of the drive spring; made analysis of keycomponents of the apparatus for the thermal deformation of the arm theory andsimulation analysis; analyzed the unlocking trigger force of SMA wires; establishedmathematical model of SMA wires to unlock power-on time to analyze differentunlocking time under different energization voltages; analyzed the smallest corner ofunlocking from the point of view of kinematics.Using ANSYS, we completed the statics and dynamics simulation analysis forSMA locking release mechanism in the locked state, verified the correctness of thedesign program and the design parameters.Based on the analysis above, we the developed a SMA locking release mechanismand test engineering prototype tooling. We completed ground testing of the SMAlocking release mechanism, including functional test, capacity test, high temperatureenvironmental test, vibration test, unlock impact test. Through experimental studyvalidated the use of spaceborne power developed by SMA locking release mechanism can achieve a good expansion capabilities, with a small volume, a short unlocking time,large capacity, high temperature resistance, anti-vibration performance, small unlockingimpact, it has great value in engineering applications.