Active Ankle - an Almost-Spherical Parallel Mechanism

Since parallel manipulators only provide restricted workspaces in comparison to their serial counterparts they cannot compete as versatile multi-purpose tools in flexible industrial setups. However, their superior properties in terms of stiffness, payload, speed, and acceleration often allow an advantageous application in more tailored use-cases. This paper lays out the concept of a novel parallel mechanism - called the ACTIVE ANKLE - which operates in an almost-spherical manner with three degrees of freedom. The text motivates the primarily intended application of the novel device as an ankle joint of a full-body exoskeleton. In addition, the paper discusses the design, the topology, results of a motion simulation, and a comparison with related mechanisms of the ACTIVE ANKLE.