Brad Holschuh

Active knit compression stockings for the treatment of orthostatic hypotension

Active knit compression stockings are compression garments with integrated smart materials (i.e. shape memory alloy wires) that apply dynamic and controllable pressures to the body to provide therapeutic compression treatment for those suffering from orthostatic hypotension (OH). Current static compression garments (e.g. elastic knit garments) exert unpredictable pressures on the body and are difficult to don/doff, especially for elderly populations most effected by OH. Alternatively, dynamic compression garments currently on the consumer market (e.g. pneumatic compression wraps) are bulky, inhibit wearer mobility, and are usually tethered to an inflation source. Active knit compression stockings offer an alternative technology for compression therapy that leverage the architecture of traditional, weft knit fabric structures to create large, amplified contractions across the textile surface. The result is a new compression garment alternative that is simultaneously dynamic, mobile, and untethered.

SqueezeBands: Mediated Social Touch Using Shape Memory Alloy Actuation

Mediated social touch technologies aim to transmit the sense of touch between two or more physically distributed partners. Previous work in CSCW has focused mostly on vibrotactile actuation, though there is also significant recent interest in exploring a wider variety of haptic actuation modalities. In this paper, we explore Shape Memory Alloys as a novel means for constriction and heat activation. We demonstrate the feasibility of this approach by implementing the SqueezeBands system, which augments social gestures over videochat with haptic actuation. We describe an evaluation of the system with 57 pairs of participants, collaborating on tasks either high or low emotional salience. Our results demonstrate that SqueezeBands encourage greater and more diverse demonstrations of touch and that they may be particularly appropriate for easing mental and physical demand in high emotion tasks. We end with a discussion of the opportunities and challenges in leveraging Shape Memory Alloy actuation for mediated social touch.

Preliminary study of the subjective comfort and emotional effects of on-body compression

The sensation of touch is integral to everyday life. Current haptics research focuses mainly on vibrations, tap, and point pressures, but the sensation of distributed pressures such as compression are often overlooked. We investigated the subjective comfort and emotional effects of applied on-body compression, specifically on the torso and upper arms, through a pilot user study incorporating a novel, low-profile, and actively-controllable compression garment. The active compression garment was embedded with contractile shape memory alloys (SMAs) to create dynamic compression on the body. Qualitative interview data collected (n=8) were used to generate a list of findings to inform the future creation of a computer-mediated compression garment that is wearable, comfortable, and safe for use.

Novel manufacturing of advanced smart garments: knitting with spatially-varying, multi-material monofilament

In this paper, we propose a novel method for knitting advanced smart garments (e.g., garments with targeted electrical or mechanical properties) using a single, spatially-varying, multi-material monofilament created using additive manufacturing (AM) techniques. By strategically varying the constitutive functional materials that comprise the monofilament along its length, it is theoretically possible to create targeted functional regions within the knitted structure. If spaced properly, functional regions naturally emerge in the knit as loops in adjacent rows align. To test the feasibility of this method, we evaluated the ability of a commercially available knitting machine (a Passap® E6000) to knit a variety of experimental and commercially available, spatially-variant monofilament. Candidate materials were tested both to characterize their mechanical behavior as well as to determine their ability to be successfully knitted. A repeatable spatial mapping relationship between 1D filament location and 2D knit location was established, enabling the ability to create a variety of 2D functional pathways (straight, linear, nonlinear) in the knit structure using a single monofilament input. Using this approach, a multi-material monofilament can be designed and manufactured to create advanced functional knits with spatially-variant properties.