Robomorphism: A Nonanthropomorphic Wearable Robot

This article describes a novel wearable robot (WR) intended to assist hip and knee flexion/ extension through series elastic actuators (SEAs). A nonanthropomorphic (NA) design was pursued to improve ergonomics while optimizing dynamic properties through a smart distribution of swinging masses. Once the anthropomorphism constraint is relaxed, the number of possible architectures becomes very high, and a methodology must be defined to point out the best options. To this purpose, a design methodology, which includes a novel approach to kinematic synthesis, topology selection, and morphological optimization, is also presented. The advantages offered by the novel architecture are demonstrated both theoretically and experimentally. In particular, the results show a low reflected inertia on the user's body, a high backdrivability, and an intrinsic tolerance to misalignments. Such advantages make the proposed robot a promising platform for the development of assistive and rehabilitation systems.