title: In Vivo Estimation of Human Forearm and Wrist Dynamic Properties.
abstract: It is important to estimate the 3 degree-of-freedom (DOF) impedance of human forearm and wrist (i.e., forearm prono-supination, and wrist flexion-extension and radial-ulnar deviation) in motor control and in the diagnosis of altered mechanical resistance following stroke. There is, however, a lack of methods to characterize 3 DOF impedance. Thus, we developed a reliable and accurate impedance estimation method, the distal internal model based impedance control (dIMBIC)-based method, to characterize the 3 DOF impedance, including cross-coupled terms between DOFs, for the first time. Its accuracy and reliability were experimentally validated using a robot with substantial nonlinear joint friction. The 3 DOF human forearm and wrist impedance of eight healthy subjects was reliably characterized, and its linear behavior was verified. Thus, the dIMBIC-based method can provide us with 3 DOF forearm and wrist impedance regardless of nonlinear robot joint friction. It is expected that, with the proposed method, the 3 DOF impedance estimation can promote motor control studies and complement the diagnosis of altered wrist and forearm resistance post-stroke by providing objective impedance estimates, including cross-coupled terms.
authors.forename: Kyungbin
authors.initials: K
authors.lastname: Park
authors.forename: Pyung-Hun
authors.initials: PH
authors.lastname: Chang
authors.forename: Sang Hoon
authors.initials: SH
authors.lastname: Kang
mesh_terms: D000054:Acceleration; D000465:Algorithms; D003198:Computer Simulation; D055119:Elastic Modulus / Q000502:physiology; D005542:Forearm / Q000502:physiology*; D006801:Humans; D008954:Models, Biological; D016059:Range of Motion, Articular / Q000502:physiology*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D013314:Stress, Mechanical; D014783:Viscosity; D014953:Wrist / Q000502:physiology*; D014955:Wrist Joint / Q000502:physiology*