Compute IK Residuals

Command

Compute_IK_Residuals
! /RESULT_FOLDER=IK_TARGET_RESIDUALS
! /SEPARATE_COMPONENTS=FALSE
;

A signal equal to the inverse Kinematic target residual will be created for every target in your IK model. The results will be under the type DERIVED.

SEPARATE_COMPONENTS is a hidden parameter by default. If SEPARATE_COMPONENTS is included and is set to TRUE, a separate signal will be created for each of the X Y and Z components. (An _X, _Y or _Z will be appended to the target name depending on the component).

Note: To guarantee that the model pose is consistent with the current IK Properties a "Build_Model" or "RECALC" should be run right before the Compute_IK_Residuals.

Background

This command can be used to calculate the residual for each target when using Inverse Kinematics is used to compute the segment Pose. The residual is the Euclidean distance between the target's expected location (obtained by transforming the fixed local coordinates of a target from segment space to lab space) and the measured location of the target by the motion capture system. The IK residuals tell the users which targets contribute the largest error to the IK fit.

An example of when this would be useful is if you have an IK model and some issues seem to be appearing. You can calculate the residuals for the targets in your IK. If one target as a higher residual than the other targets in your model, you may want to consider removing this target from the list of tracking targets.