Optimal reaching trajectories based on feedforward control
- 4 June 2022
- journal article
- research article
- Published by Springer Science and Business Media LLC in Biological Cybernetics
- Vol. 116 (4), 517-526
- https://doi.org/10.1007/s00422-022-00939-4
Abstract
In human upper-arm reaching movements, the variance of the hand position increases until the middle of the movement and then decreases toward the endpoint. Such decrease in positional variance has been suggested as an evidence to support the hypothesis that our nervous system uses feedback control, rather than feedforward control, for arm reaching tasks. In this study, we computed the optimal trajectories based on feedforward control under several criteria for a one-link two-muscle arm model with considering the stochastic property of muscle activities in order to reexamine the hypothesis. The results showed that the feedforward control also represents the decrease in positional variance in the latter half of the movement when the control signal is planned under the minimum energy cost and minimum variance models. Furthermore, the optimal trajectory that minimizes energy cost represents not only the decrease in positional variance but also many other characteristics of the human reaching movements, e.g., the three-phasic activity of antagonistic muscle, bell-shaped speed curve, N-shaped equilibrium trajectory, and bimodal profile of joint stiffness. These results suggest that minimum energy cost model well expresses the characteristics of hand reaching movements, and our central nervous system would make use of not only a feedback control but also feedforward control.Keywords
This publication has 48 references indexed in Scilit:
- Constraint and exploitation of redundant degrees of freedom during walkingRobotics and Autonomous Systems, 2012
- Cerebellum Predicts the Future Motor StateThe Cerebellum, 2008
- Control of mental activities by internal models in the cerebellumNature Reviews Neuroscience, 2008
- An analytical estimation of the energy cost for legged locomotionJournal of Theoretical Biology, 2006
- Optimal Impedance Control for Task Achievement in the Presence of Signal-Dependent NoiseJournal of Neurophysiology, 2004
- Mechanical and metabolic determinants of the preferred step width in human walkingProceedings. Biological sciences, 2001
- A Theory of Metabolic Costs for Bipedal GaitsJournal of Theoretical Biology, 1997
- Forward Models for Physiological Motor ControlNeural Networks, 1996
- Minimum Muscle-Tension Change Trajectories Predicted by Using a 17-Muscle Model of the Monkey's ArmJournal of Motor Behavior, 1996
- Virtual trajectory and stiffness ellipse during multijoint arm movement predicted by neural inverse modelsBiological Cybernetics, 1993