4D printing of soft orthoses for tremor suppression

Abstract

Tremor is an involuntary and oscillatory movement disorder that makes daily activities difficult for affected patients. Hand tremor-suppression orthoses are noninvasive, wearable devices designed to mitigate tremors. Various studies have shown that these devices are effective, economical, and safe; however, they have drawbacks such as large weight, awkward shape, and rigid parts. This study investigates different types of tremor-suppression orthoses and discusses their efficiency, mechanism, benefits, and disadvantages. First, various orthoses (with passive, semi-active, and active mechanisms) are described in detail. Next, we look at how additive manufacturing (AM) has progressed recently in making sensors and actuators for application in tremor orthoses. Then, the materials used in AM are further analyzed. It is found that traditional manufacturing problems can be solved with the help of AM techniques, like making orthoses that are affordable, lighter, and more customizable. Another concept being discussed is using smart materials and AM methods, such as four-dimensional (4D) printing, to make orthoses that are more comfortable and efficient. Graphic abstract

3D‐Printed Phase‐Change Artificial Muscles with Autonomous Vibration Control

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Free-Form Liquid Crystal Elastomers via Embedded 4D Printing

“…AM is most well known for on-demand fabrication of geometrically complex 3D shapes, some of which are impossible to create by using traditional manufacturing techniques. Meanwhile, advances in stimulus-responsive materials such as hydrogels, shape memory polymers, magneto-active materials, and liquid crystal elastomers (LCEs) have demonstrated unique promise for the fabrication of smart, responsive structures that have found widespread applications in biomedical devices, − soft robots, − and deployable structures. − When 3D-printed, smart materials can transform as a function of time, leading to a new paradigm of printing called 4D printing …”