A limitation of a simple linear mass-spring model in describing goal
directed movements is that it generates rather slow movements when
the parameters are kept within a realistic range. Does this imply
that the control of fast movements cannot be approximated by a linear
system? In servo-control theory, it has been proposed that an optimal
controller should control movement velocity in addition to position.
Instead of explicitly controlling the velocity, we propose to modify
a simple linear mass-spring model. We replaced the damping relative
to the environment (absolute damping) with damping with respect to
the velocity of the equilibrium point (relative damping). This gives
the limb a tendency to move as fast as the equilibrium point. We
show that such extremely simple models can generate rapid single-joint
movements. The resulting maximal movement velocities were almost
equal to those of the equilibrium point, which provides a simple
mechanism for the control of movement speed. We further show that
peculiar experimental results, such as an ?N-shaped? equilibrium
trajectory and the difficulties to measure damping in dynamic conditions,
may result from fitting a model withabsolute damping where one withrelative
damping would be more appropriate. Finally, we show that the model
with relative damping can be used to model subtle differences between
multi-joint interceptions. The model with relative damping fits the
data much better than a version of the model with absolute damping
%0 Journal Article
%1 Lussanet2002
%A de Lussanet, Marc H.E.
%A Smeets, Jeroen B. J.
%A Brenner, Eli
%D 2002
%J Human Movement Science
%K Arm Equilibrium Human; Interception; Model; Motor control; movements; point
%P 85-100
%T Relative damping improves linear mass-spring models of goal-directed
movements
%V 21
%X A limitation of a simple linear mass-spring model in describing goal
directed movements is that it generates rather slow movements when
the parameters are kept within a realistic range. Does this imply
that the control of fast movements cannot be approximated by a linear
system? In servo-control theory, it has been proposed that an optimal
controller should control movement velocity in addition to position.
Instead of explicitly controlling the velocity, we propose to modify
a simple linear mass-spring model. We replaced the damping relative
to the environment (absolute damping) with damping with respect to
the velocity of the equilibrium point (relative damping). This gives
the limb a tendency to move as fast as the equilibrium point. We
show that such extremely simple models can generate rapid single-joint
movements. The resulting maximal movement velocities were almost
equal to those of the equilibrium point, which provides a simple
mechanism for the control of movement speed. We further show that
peculiar experimental results, such as an ?N-shaped? equilibrium
trajectory and the difficulties to measure damping in dynamic conditions,
may result from fitting a model withabsolute damping where one withrelative
damping would be more appropriate. Finally, we show that the model
with relative damping can be used to model subtle differences between
multi-joint interceptions. The model with relative damping fits the
data much better than a version of the model with absolute damping
@article{Lussanet2002,
abstract = {A limitation of a simple linear mass-spring model in describing goal
directed movements is that it generates rather slow movements when
the parameters are kept within a realistic range. Does this imply
that the control of fast movements cannot be approximated by a linear
system? In servo-control theory, it has been proposed that an optimal
controller should control movement velocity in addition to position.
Instead of explicitly controlling the velocity, we propose to modify
a simple linear mass-spring model. We replaced the damping relative
to the environment (absolute damping) with damping with respect to
the velocity of the equilibrium point (relative damping). This gives
the limb a tendency to move as fast as the equilibrium point. We
show that such extremely simple models can generate rapid single-joint
movements. The resulting maximal movement velocities were almost
equal to those of the equilibrium point, which provides a simple
mechanism for the control of movement speed. We further show that
peculiar experimental results, such as an ?N-shaped? equilibrium
trajectory and the difficulties to measure damping in dynamic conditions,
may result from fitting a model withabsolute damping where one withrelative
damping would be more appropriate. Finally, we show that the model
with relative damping can be used to model subtle differences between
multi-joint interceptions. The model with relative damping fits the
data much better than a version of the model with absolute damping},
added-at = {2009-06-26T15:25:19.000+0200},
author = {de Lussanet, Marc H.E. and Smeets, Jeroen B. J. and Brenner, Eli},
biburl = {https://www.bibsonomy.org/bibtex/2b2ef6812715cfd9389685fde3889222e/butz},
comment = {Besseres mass-spring-model für goaldirected movement, in dem die dämpfung
relativ zur GEschwindigkeit des EPs gesetzt wird},
description = {diverse cognitive systems bib},
interhash = {c183c065869780fb6ea8fd1f4ffea3ab},
intrahash = {b2ef6812715cfd9389685fde3889222e},
journal = {Human Movement Science},
keywords = {Arm Equilibrium Human; Interception; Model; Motor control; movements; point},
owner = {martin},
pages = {85-100},
timestamp = {2009-06-26T15:25:46.000+0200},
title = {Relative damping improves linear mass-spring models of goal-directed
movements},
volume = 21,
year = 2002
}