Specifications

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AnyRefFrame &Ins = .Arm.M2Insertion;
SPLine.StringMesh = 20;
SPLine.InitWrapPosVectors = {{-0.2, -0.2, 0},{-0.05,-0.2, 0}};
AnyDrawMuscle drw = {
Bulging = 0;
ColorScale = 1;
MaxStress = 250000;
};
};
Finally, to have a more clean-cut case, we temporarily remove the external force that we previously added
/*AnyForce3D Load = {
AnyRefNode &Attachment = .Arm.Hand;
F = {-100, -100, 0};
};
*/
We are ready to try running the InverseDynamicAnalysis again. Load the model, pick
InverseDynamicAnalysis in the operations tree, and click the Run button. The arm should move as is did in
the previous section. Now, using a Chart View we can investigate the behavior of the new muscle. In the
Chart View's tree, expand the folders as far as Muscle2, and try charting some of the parameters.
The key to understanding the muscle's behavior is to study the forces in the muscle's different elements.
The chart of Fm, which is the force in the muscle's contractile element, is very uninteresting. This muscle
does not contribute to carrying the load, and hence the system does not activate it. But the muscle is not
without force. The property Fp, which is the force in the parallel-elastic element of the muscle has the
following behavior:
In the initial phase of the movement, the parallel-elastic element is slack and adds no force to the muscle.
But as the muscle gets extended, the passive muscle force sets in, and it continues to rise as the movement
progresses. Notice that this passive force acts against the movement and hence requires Muscle1 to work
that much more. But the passive force has another interesting effect, which we can see if we chart the
property Lt, i.e. the length of the tendon (Notice that we have changed the scale of the ordinate axis):