Cable-driven robotic interface for lower limb neuromechanics identification

TL;DR

This paper introduces a versatile cable-driven robotic interface capable of accurately investigating lower limb neuromechanics in natural postures, overcoming limitations of existing devices and enabling precise impedance identification.

Contribution

The paper presents a novel, highly dynamic, and kinematically unconstrained cable-driven interface for lower limb neuromechanics assessment, suitable for upright postures during walking or standing.

Findings

Interface exhibits rigidity above 500N/m with low viscosity.

Accurately identifies limb mechanical impedance using dummy tests.

Successfully tests smooth perturbation for hip neuromechanics estimation.

Abstract

This paper presents a versatile cable-driven robotic interface to investigate the single-joint joint neuromechanics of the hip, knee and ankle. This endpoint-based interface offers highly dynamic interaction and accurate position control, as is typically required for neuromechanics identification. It can be used with the subject upright, corresponding to natural posture during walking or standing, and does not impose kinematic constraints on a joint, in contrast to existing interfaces. Mechanical evaluations demonstrated that the interface yields a rigidity above 500N/m with low viscosity. Tests with a rigid dummy leg and linear springs show that it can identify the mechanical impedance of a limb accurately. A smooth perturbation is developed and tested with a human subject, which can be used to estimate the hip neuromechanics.