This paper presents the design and development of a highly articulated, continuum, wearable, fabric-based Soft Poly-Limb (fSPL). This fabric soft arm acts as an additional limb that provides the wearer with mobile manipulation assistance through the use of soft actuators made with high-strength inflatable fabrics. In this work, a set of systematic design rules is presented for the creation of highly compliant soft robotic limbs through an understanding of the fabric based components behavior as a function of input pressure. These design rules are generated by investigating a range of parameters through computational finite-element method (FEM) models focusing on the fSPL's articulation capabilities and payload capacity in 3D space. The theoretical motion and payload outputs of the fSPL and its components are experimentally validated as well as additional evaluations verify its capability to safely carry loads 10.1x its body weight, by wrapping around the object. Finally, we demonstrate how the fully collapsible fSPL can comfortably be stored in a soft-waist belt and interact with the wearer through spatial mobility and preliminary pick-and-place control experiments.

In this paper, we present the design, fabrication, and evaluation of robust, fabric-reinforced textile actuators, which are capable of performing a variety and combination of motions, such as axial extension, radial expansion, bending, and twisting along its central axis. A simple fabrication procedure using a combination of lamination and sewing is described. The relationship between the fabric reinforcement characteristics and the actuator deformation is studied and experimentally verified. Multi-segment actuators can be created by tailoring different sections of fabric-reinforcements together in order to generate combination of motions to perform specific tasks. We demonstrate this by designing an anthropomorphic soft robotic hand and providing preliminary evaluations on grasping daily living objects of various size and shapes.

This paper investigates the design of a soft elbow exosuit capable of providing supplemental lifting assistance by reducing muscle activity of the bicep muscle. The aim is to improve the efficiency and endurance of workers who are tasked with repetitive lifting. The design consists of an array of pneumatically pressurized soft actuators, which are encased in nylon fabric that allows for a high force-to-weight ratio of 211.SN/g. An analytical model governing the bending behavior of two consecutive actuators and torque generated by the exosuit is developed, with test results showing less than 10% error from the theoretical model. An elbow joint torque value of 27.6N.m is achieved at 300kPa, which is comparable to the 30N.m maximum set by OSHA requirements in the USA. Further testing with a healthy participant is performed using surface electromyography (sEMG) sensors and a motion capture system to assess the capabilities of the exosuit to provide active assistance to the bicep during isometric and concentric contractions. Measurable assistance to lifting is observed with minimal obstruction to the user's range of motion for all experiments.

This paper presents the design, development and preliminary evaluation of a soft-inflatable exosuit for knee rehabilitation. Soft-inflatable actuators made of heat-sealable thermoplastic polyurethane (TPU) materials are fabricated in two different beam-like structures (I and O cross-section actuators) and mechanically characterized for their torque performance in knee-extension assistance. The fabrication procedure of both types of actuators is presented as well as their integration into a lightweight, low-cost and body-conforming interface. To detect the activation duration of the device during the gait cycle, a soft-silicone insole with embedded force-sensitive resistors (FSRs) is used. In evaluation studies, the soft-inflatable exosuit device is tested for its ability to reduce muscle activity during the swing phase of the knee. Using sEMG (surface electromyography) sensors, the rectus femoris muscle group of a healthy individual is recorded while walking on a treadmill at a constant speed, with and without the soft device. Preliminary testing presents a promising 7% reduction in muscle activity and demonstrates the applicability of the soft-inflatable exosuit in knee rehabilitation scenarios.