A reusable SMA actuated non-explosive lock-release mechanism for space application

Abstract

After the satellite is launched with the carrier rocket, it is necessary to separate the satellite from the rocket at an appropriate time to ensure that the satellite enters the intended orbit. In this process, it is vital to ensure a reliable connection and accurate separation. With the increasing use of microsatellite in orbit, the contradiction between the shock of separation and the requirement of the platform’s dynamic environment is becoming increasingly prominent. Therefore, the traditional pyrotechnic separation device can no longer meet the requirements. This paper presents a reusable non-explosive release actuator using shape memory alloy (SMA) wire for high load and low shock. The system is based on the Fast Acting Shock-less Separation Nut (FASSN) technology. Using the shape memory effect of SMA, a biased SMA wire trigger has been developed, which is used as the driver source of the actuator. At the moment of receiving the electrical signal, the SMA wire generates stress and deformation. The trigger set free the constraints on the mechanical components, and the target is released. Experimental results indicate that the trigger device can unlock successfully and well meet the technical objectives.

Keywords

• sma actuator
• non-explosive
• lock-release
• space application