Specifications

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m/s^2 or 30 g. Notice that this is for the thorax and not a distal segment like a hand or a foot. It is not
realistic, and it is in fact an artifact produced by the amplification of small errors in the positional
signal through the two subsequent differentiations.
If you work with recorded movement data, then it is very important to check that the accelerations are
within reasonable limits. The movement is input in inverse dynamics, and if the accelerations are unrealistic,
then the muscle and joint forces will be too.
Too high acceerations are usually due to lack of smoothness of the recorded motion data. The solution is
often to apply smoothing with a low pass filter to reduce the unrealistic acceleratons.
Parameter studies and optimization
The AnyBody Modeling System has a nice mechanism that allows you to perform investigations of the
model's reaction to its parameters and even to automatically find the set of parameters that causes a given
behavior of the model. Some examples of applications are:
• Systematic investigations of the model's sensitivity to a group of parameters such as a muscle
insertion point, muscle strength, or external support point.
• Posture and movement prediction.
• Optimization of muscular strength for a particular sports performance.
• Optimization of the layout of a bicycle for a particular person.
• Answering research questions such as: Could a T. rex jump? With optimization you can find the
movement pattern that maximizes, for instance, the jump height given the body weight and
limitations on muscular strength.
Parameter study: Metabolic efficiency of a bicycle as a function of seat height and seat horizontal position.
This functionality is provided through two complementary studies
:
The AnyParamStudy performs an exhaustive search of the variable space computing the model's reaction
to every combination of the variables within a given interval. For instance, a parameter study could
investigate the metabolic efficiency of a bicycle depending on the horizontal and vertical position of the
saddle. The advantage of this study is that it gives you the ultimate overview of the system's behavior. The