Specifications

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The idea behind this system is to make the human model and the environment model as independent of
each other as possible.
Some models also have a folder called Mannequin for control of posture.
Validation of models
Somewhere on the way to the decision of using a biomechanical model you have probably asked yourself
the question: Will I be able to trust the results I get?
This is a very relevant question indeed. Computer models are just that: a model of reality, and there will
always be some amount of approximation involved. The good news is that with careful modeling and the
'right model for the right problem' you can get very close to reality with the AnyBody Modeling System
because it is tailor-made for the complexity of musculoskeletal systems.
Investigation of the accuracy of the model goes under the term 'validation', and this is what we will be
dealing with in this tutorial. More precisely, you can expect to find the following in this tutorial:
1. Clever ideas for validation methods.
2. Examples of models that have been validated previously.
What can go wrong?
Well, lots, actually. But it is helpful to try to categorize the matter into a few sources of error.
• Errors sources in the model
• Errors sources in the basic assumptions
• Errors sources in the software
Errors sources in the model
An AnyScript model contains a lot of data, and they are all infested with some degree of inaccuracy:
Geometry and mass properties of segments, assumptions about the kinematics and reactions of joints,
properties and attachment points of muscles, and much more.
It has been said about biomechanics that there is a 'right' model for each case. For instance, there is little
point in using a complex muscle model if you have little information about the muscle properties, for
instance fiber lengths and pennation angles. Another consideration is the level of subject-specific accuracy.
Is the purpose of the model to simulate a particular individual, or should it reflect a cross section of the
population?