Deployment performance of shape memory polymer composite hinges at low temperature

Abstract

Shape memory polymer composite hinges, adapted for possible space applications, were successfully designed and fabricated, and performance tests at room temperature confirmed their full recoverability in our previous studies. Since shape memory polymer composite hinges are intended for space applications, they should be able to operate at low temperature. Even though the deployment of the hinge at room temperature triggered by the stimulation of a heating element has been quite promising, a suitable design for a shape memory polymer composite hinge with a heating element is more important at low temperatures because shape memory polymer composite hinges lose much heat to the environment. The recoverability of shape memory polymer composite hinges and the impact of the heating element design on the deployment time at low temperature are brought to light in this article. A shape memory polymer composite hinge with an attached heating element was fabricated as in our previous studies. The necessary power and supply power for deployment of the shape memory polymer composite hinge at a low temperature of –10°C were calculated, and a finite element analysis for the heating process was performed with the supply power. A folding and deployment test of the shape memory polymer composite hinge at –10°C was performed to show its shape recoverability. However, the shape memory polymer composite hinge did not deploy to its original shape. To determine the reason, measurements of temperature distribution were done using an infrared camera and thermocouples. The results revealed that the low temperature along the two side edges of the shape memory polymer composite tape prevented full deployment of the shape memory polymer composite hinge, which also revealed the need for design modification. The folding and deployment test of our modified shape memory polymer composite hinge demonstrated a nearly full deployment.

Design and optimization of self-deployable damage tolerant composite structures: A review

“…The dimensions of the shape memory alloy used as a damping mechanism were selected considering the torque applied by the tape-spring. The use of SMM has been a point of interest for several studies [54,128,132,133,139,141], which are not within the scope of the present review. For more information and for an updated review on the use of SMM in deployable systems, the interested reader is referred to [132,141].…”

Thermomechanical Performance of Bio-Inspired Corrugated-Core Sandwich Structure for a Thermal Protection System Panel

“…The initial temperature of the sandwich structure is assumed to be 295 K. Owing to the unknown ambient temperature during a flight mission of the vehicle, we also assumed the ambient temperature for the simulation. The natural convection coefficient is determined by considering the Nusselt number and characteristic length of the surface [6,37,38]. The ambient temperature and natural convection coefficient are given in detail in Table 4 [34].…”

Distributed sensing based real‐time process monitoring of shape memory polymer components

“…21 Thermal imaging cameras and thermocouples have been used to investigate the heat distribution inside SMPCs during the shape memory process. 20,22 Moreover, surface-mounted fiber Bragg grating (FBG) sensors have the ability to measure temperature and strain variations for a short distance (approximately 1 cm) on an SMPC. 23,24 Thus far only a few prototype SMPC applications have been monitored during their shape memory process at the actual operational environment.…”

“…Furthermore, the digital image correlation (DIC) technique is able to monitor the strain changes in SMPCs during their thermomechanical cycles 21 . Thermal imaging cameras and thermocouples have been used to investigate the heat distribution inside SMPCs during the shape memory process 20,22 . Moreover, surface‐mounted fiber Bragg grating (FBG) sensors have the ability to measure temperature and strain variations for a short distance (approximately 1 cm) on an SMPC 23,24 .…”