How to Use IAA

analyze -S subject01_Setup_IAA.xml

<InducedAccelerations name="InducedAccelerations">
  
<!--Flag (true or false) specifying whether whether on. -->
<on> true </on>
 
<!-- Starting time for the Analysis.-->
<start_time> 0.0 </start_time>
 
<!--End time for the Analysis.-->
<end_time> 1.5 </end_time>
 
<!--Specifies how often to store results during a simulation.-->
<step_interval> 10 </step_interval>
 
<!--Flag (true or false) indicating whether output angles are in degrees.-->
<in_degrees> true </in_degrees>
 
<!--Names of the coordinates for which to compute induced accelerations. The key word 'All' indicates that the analysis should be performed for all coordinates.-->
<coordinate_names> knee_angle_r </coordinate_names>

<!--Names of the bodies for which to compute induced accelerations. The key word 'All' indicates that the analysis should be performed for all bodies. Use 'center_of_mass' for the induced accelerations of the system mass center -->
<body_names> center_of_mass </body_names>

<!-- ConstraintSet for replacing the ExternalForces applied to the model. The analysis expects a constraint for every ExternalForce applied to the model and that the corresponding constraint is listed in the same order. -->
<ConstraintSet>
  <objects>
  <RollingOnSurfaceConstraint name="right_foot_contact">
  
    <!-- Specify to disable constraint by default -->
    <isDisabled> true </isDisabled>

    <!-- Specify the rolling body for this constraint -->
    <rolling_body> calcn_r </rolling_body>

    <!-- Specify the body containing the surface (plane) that the rolling body rolls on. -->
    <surface_body> ground </surface_body>

    <!-- Surface's normal direction defined in the surface body -->
    <surface_normal> 0 1 0 </surface_normal>

    <!-- Surface height in the direction of the normal in the surface body: -->
    <surface_height> 0 </surface_height>

    <!-- Coulomb friction coefficient for rolling on the surface-->
    <friction_coefficient> 0.75 </friction_coefficient>

    <!-- A guess at the area of contact approximated by a circle-->
    <contact_radius> 0.01 </contact_radius>
  </RollingOnSurfaceConstraint>

  <RollingOnSurfaceConstraint name="left_foot_contact">
    <!-- Specify to disable constraint by default -->
    <isDisabled> true </isDisabled>

    <!-- Specify the rolling body for this constraint -->
     <rolling_body> calcn_l </rolling_body>

    <!-- Specify the body containing the surface (plane) that the rolling body rolls on. -->
    <surface_body> ground </surface_body>

    <!-- Surface's normal direction defined in the surface body -->
    <surface_normal> 0 1 0 </surface_normal>

    <!-- Surface height in the direction of the normal in the surface body -->
    <surface_height> 0 </surface_height>

    <!-- Coulomb friction coefficient for rolling on the surface: -->
    <friction_coefficient> 0.75 </friction_coefficient>

    <!-- A guess at the area of contact approximated by a circle -->
    <contact_radius> 0.01 </contact_radius>
  </RollingOnSurfaceConstraint>
  </objects>
</ConstraintSet>

<!-- Minimum magnitude of force necessary to turn on constraint.-->
<force_threshold> 6 </force_threshold>

<!-- Only compute the potential (acceleration/N) of an actuator to accelerate the model..-->
<compute_potentials_only> false </compute_potentials_only>

<!-- Report individual (induced) force contributions to constraint reactions forces in addition to resulting accelerations -->
<report_constraint_reactions> true </report_constraint_reactions>
 
</InducedAccelerations>