Abstract: A robotic orthosis device (10) for assisting a user to rotate their wrist is disclosed. The robotic orthosis device includes a pair of fabric-based helical actuators (26, 28) and a sleeve (12) or rigid interfaces (90, 92) configured to attach to a user's forearm. Each of the helical actuators includes a cylinder (30, 30?) and a pneumatic bladder (40) configured to inflate the cylinder. Each cylinder includes an anisotropic sheet material (32) and a base sheet material (34) running the length of the cylinder. The anisotropic sheet material comprises elastomeric strands (74) that enable the material to stretch in a preferred direction. This preferred direction is parallel to the orientation of the elastomeric strands, but different than the longitudinal axis of the cylinder. The base sheet material, which is affixed to the anisotropic sheet material, is strain-limiting along the longitudinal axis.