Unifying system identification and biomechanical formulations for the estimation of muscle, tendon and joint stiffness during human movement

Abstract

Unifying system identification and biomechanical formulations for the estimation of muscle, tendon and joint stiffness during human movement To cite this article: Christopher P Cop et al 2021 Prog. Biomed. Eng. 3 033002 View the article online for updates and enhancements.

Simultaneous Quantification of Ankle, Muscle, and Tendon Impedance in Humans

“…Recently, a theoretical framework has been developed to determine how muscle and tendon stiffness contribute to the net mechanics of the joint [38]. Though the framework has been presented for a similar purpose as our work, its approach to estimation relies on models that may bias the estimated quantities [39].…”

A Multi-Modal Under-Sensorized Wearable System for Optimal Kinematic and Muscular Tracking of Human Upper Limb Motion

“…The evaluation of the musculoskeletal state of the human body is crucial for different applications, such as rehabilitation and assistive technologies [ 1 ], sportsmen monitoring [ 2 , 3 ] and human-robot interaction and collaboration [ 4 ]. Such a monitoring is also important to prevent possible work-related musculoskeletal disorders, providing tools for a proper ergonomics evaluation [ 5 , 6 , 7 ] informed by suitably devised bio-mechanical models [ 8 ].…”

Estimating Biological Stiffness Without Relying on External Joint Perturbations: A Musculoskeletal Modeling Framework

“…where F max is the muscle's maximum isometric force, f a ( lM ), f v (ṽ M ), and f p ( lM ) are generic dimensionless active force-length, force-velocity, and passive forcelength relationships, respectively, lM and ṽM are the muscle fiber's normalized length and velocity, respectively, d = 0.1 is a damping factor to avoid model singularities when muscles are inactive [96], and ϕ is the muscle fiber's pennation angle. MTU stiffness, K M T U , is computed as the series arrangement of the equivalent muscle fiber's stiffness in the tendon's line of action, K M eq , and the tendon's stiffness, K T , [125]:…”

“…Human movement results from the interaction between the neuromusculoskeletal system and the environment [58]. The coordinated activity of all muscles spanning a joint largely defines net joint torque and joint stiffness [125], thereby enabling versatile navigation and adaptation to external mechanical demands [47]. The ability to determine the muscle force profiles underlying a given movement is crucial to understand how joint torque and stiffness are modulated to enable large repertoires of movements.…”

“…In this context, muscle-tendon units (MTUs) are predominantly modeled using Hill-type muscle formulations, based on parameters that vary non-linearly across individuals. However, for the same person, and for the same combination of joint angle and torque profiles, different model parameters could potentially result in different muscle force and joint stiffness solutions [125]. Therefore, robust identification of MTU parameters on a subject-specific basis is necessary to understand how muscles contribute to modulate joint stiffness during movement.…”