Design and analysis of shockless smart releasing device based on shape memory polymer composites

In this paper, a new releasing device with the advantages of non-pyrotechnic, shockless, re-settable, and simple structured are presented. A sandglass-like mechanism is designed and it is made of carbon fiber reinforced epoxy-based shape memory polymer (SMP) and its composite (SMPC). The SMPC active element is the outer part, while the inner part is made of metal with a sandglass-like profile. The active element is designed to change shape and accomplish a separation between the mating parts of the release mechanism with no impact. The actuation of the SMPCs parts is not an instant but duration, so that the considerable preload will be released gently and with no impacting shock. Some basic mechanical tests for SMP and SMPC plate specimens were done to determine the basic mechanical properties of the epoxy-based SMP and SMPC. The locking-compression test, axial tensile test and relaxation test were conducted to determine the mechanical properties of the smart releasing device. The recovery experiment of the device was also applied and the scanning electron microscope (SEM) was used to observe the morphologies of the SMPC cylinders of the smart releasing devices before and after releasing.