Optimization and Systems Theory Seminar
Friday, March 13, 1998, 11.00-12.00, Room 3721,
Lindstedtsvägen 25
Yssa DeWoody
Department of Mathematics,
Texas Tech. University,
Lubbock, Texas, USA
A direct approach utilizing musculoskeletal dynamics and neuromuscular
control to determine stress development in bone
The role of forces produced by the musculotendon units in the stress
development of the long bones during gait has not been fully analyzed. It is
well known that the musculotendons act as actuators producing the joint
torques which drive the body. Although the joint torques required
to perform certain motor tasks can be recovered through a kinematic
analysis, it remains a difficult problem to determine the actual forces
produced by each muscle that resulted in these torques. As a
consequence, few studies have focused on the role of individual muscles in
the development of stress in the bone.
This study takes a control theoretic approach to the problem. A seven
link, eight DOF model of the body is controlled by various muscle
groups on each leg to simulate gait. The simulations incorporate
Hill-type models of muscles with activation and contraction dynamics
controlled through neural inputs. This direct approach allows one to
know the exact muscle forces exerted by each musculotendon throughout
the gait cycle as well the joint torques and reaction forces at the
ankle and knee. Stress and strain computed by finite element analysis
on skeletal members will be related to these derived loading
conditions. Thus the role of musculoskeletal dynamics and
neuromuscular control in the stress development of the tibia during
gait can be analyzed.
Calendar of seminars
Last update: March 5, 1998 by
Anders Forsgren,
andersf@math.kth.se.