Preliminary experimental investigation of control parameters for the electroresistive heating of SMA knitted textiles

Rachel Marbaker, Kevin Eschen, Brent Utter, Julianna Abel

Research output: Chapter in Book/Report/Conference proceedingConference contribution

Abstract

Knitted textiles manufactured from shape memory alloy (SMA) monofilaments possess advanced capabilities for distributed and complex actuation and are suited for a range of emerging needs in aerospace, biomedical, and robotics applications. In general, high currents for short periods of time provide sufficient electroresistive (Joule) heat to cause SMA wires to transform to austenite. However, SMA knitted textiles are difficult to electroresistively heat because the interlocking knit structure short-circuits the flow of current, causing localized overheating and isolating the transformation of the material along the current path. One approach for heating SMA knitted textiles is to drive pulses of high current between pairs of electrodes positioned across horizontal courses (rows) of knitted loops. This research presents a preliminary experimental investigation of the effects of factors related to electroresistive heating for SMA knitted textiles. A design of experiments analysis with two levels of four factors was conducted using a 24-1 fractional factorial design. The factors included the voltage of the power supply connected to the current amplifiers; a geometric factor defining the horizontal spacing of the electrodes attached to the knit sample; and two waveform factors: On Cycles and Off/On Cycles, which defined the length of time each current amplifier was enabled and disabled. Actuation performance was quantified by the actuation displacement and actuation force of the knit sample. Preliminary results suggest that voltage is the most influential factor, but also indicate that interactions between the geometric and waveform factors have significant effects on the heating and actuation performance. The characterization of these factor interactions has the potential to inform optimal electroresistive heating approaches for SMA knitted textiles, enabling integration into applications such as wearable technologies where convective heating is not practical.

Original languageEnglish (US)
Title of host publicationASME 2019 Conference on Smart Materials, Adaptive Structures and Intelligent Systems, SMASIS 2019
PublisherAmerican Society of Mechanical Engineers (ASME)
ISBN (Electronic)9780791859131
DOIs
StatePublished - Jan 1 2019
EventASME 2019 Conference on Smart Materials, Adaptive Structures and Intelligent Systems, SMASIS 2019 - Louisville, United States
Duration: Sep 9 2019Sep 11 2019

Publication series

NameASME 2019 Conference on Smart Materials, Adaptive Structures and Intelligent Systems, SMASIS 2019

Conference

ConferenceASME 2019 Conference on Smart Materials, Adaptive Structures and Intelligent Systems, SMASIS 2019
CountryUnited States
CityLouisville
Period9/9/199/11/19

    Fingerprint

Cite this

Marbaker, R., Eschen, K., Utter, B., & Abel, J. (2019). Preliminary experimental investigation of control parameters for the electroresistive heating of SMA knitted textiles. In ASME 2019 Conference on Smart Materials, Adaptive Structures and Intelligent Systems, SMASIS 2019 (ASME 2019 Conference on Smart Materials, Adaptive Structures and Intelligent Systems, SMASIS 2019). American Society of Mechanical Engineers (ASME). https://doi.org/10.1115/SMASIS2019-5666