Textile based pneumatic actuators have recently seen increased development for use in wearable applications thanks to their high strength to weight ratio and range of achievable actuation modalities. However, the design of these textile-based actuators is typically an iterative process due to the complexity of predicting the soft and compliant behavior of the textiles. In this work we investigate the actuation mechanics of a range of physical prototypes of unfolding textile-based actuators to understand and develop an intuition for how the geometric parameters of the actuator affect the moment it generates, enabling more deterministic designs in the future. Under benchtop conditions the actuators were characterized at a range of actuator angles and pressures (0-136 kPa), and three distinct performance regimes were observed, which we define as Shearing, Creasing, and Flattening. During Flattening, the effects of both the length and radius of the actuator dominate with maximum moments in excess of 80 Nm being generated, while during Creasing the radius dominates with generated moments scaling with the cube of the radius. Low stiffness spring like behavior is observed in the Shearing regime, which occurs as the actuator approaches its unfolded angle. A piecewise analytical model was also developed and compared to the experimental results within each regime. Finally, a prototype actuator was also integrated into a shoulder assisting wearable robot, and on-body characterization of this robot was performed on five healthy individuals to observe the behavior of the actuators in a wearable application. Results from this characterization highlight that these actuators can generate useful on-body moments (10.74 Nm at 90°a ctuator angle) but that there are significant reductions compared to bench-top performance, in particular when mostly folded and at higher pressures.

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Soft fluidic robots are typically controlled using manifolds containing large and rigid electromechanical valves. These bulky controllers limit scalability and hinder motion, in particular for untethered soft robots. There has been recent interest in using fluidic controllers analogous to electrical logic gates and microcontrollers to replace rigid valve systems. However, these microfluidic networks typically operate with small volumes, low flow rates, and low pressures relative to what is needed to power fluidic soft actuators. This article presents the design, fabrication, and analysis of a soft, fluidic amplifier as the “missing link” between microfluidic analogies of microcontrollers and the high fluidic power loads representative of soft actuators. The article demonstrates amplification gains of pressure signals up to a factor of four. The amplifier is a step toward fully autonomous soft robots by allowing designers to develop control strategies from soft materials with minimal additional rigid components or tethering.

A wide range of engineering applications, ranging from civil to space structures, could benefit from the ability to construct material-efficient lattices that are easily reconfigurable. The challenge preventing modular robots from being applied at large scales is mainly the high level of complexity involved in duplicating a large number of highly integrated module units. We believe that reconfigurability can be more effectively achieved at larger scales by separating the structural design from the rest of the functional components. To this end, we propose a modular chainlike structure of links and connector nodes that can be used to fold a wide range of two-dimensional (2D) or three-dimensional (3D) structural lattices that can be easily disassembled and reconfigured when desired. The node geometry consists of a diamondlike shape that is one-twelfth of a rhombic dodecahedron, with magnets embedded on the faces to allow a forceful and self-aligning connection with neighboring links. After describing the concept and design, we demonstrate a prototype consisting of 350 links and experimentally show that objects with different shapes can be successfully approximated by our proposed chain design.

Interpersonal sensitivity may be an important individual difference in vulnerability to sexual dysfunction after testicular cancer. Enhancement of coping skills may be a useful direction for intervention development for interpersonally sensitive young men with cancer.