VR Mocap Studio allows one to capture animations for additional service bones attached to the root-bone that don't control skinned mesh vertices. Also, service bones can be used to record IK-targets for wrists, feet, elbows, knees, etc., as well as to record raw coordinates of the VR-headset, controllers, and Vive Trackers.
Move to the tab Passive Bones and press + to add a new binding.
In the left field, select the name of a service bone (for instance, ik_elbow_r). Select the source of data for it in the right field.
Service bones are processed differently depending on chosen data source.
The coordinates of Locator_ElbowRight, Locator_ElbowLeft, Locator_KneeRight, Locator_KneeLeft, HMD, MotionControllerRight, MotionControllerLeft, TrackedDevice1..8 will be directly transferred to the selected bone if any of them are chosen.
An offset will be added to the coordinates of the bone corresponding to the position of a service bone relative to it in the reference pose if the service bone is attached to one of the basic skeletal bones specified in tab Skeleton. For instance, if in the initial model ik_hand_r was co-aligned with PalmRight, but it is shifted by 5 cm forward, then this shift would be saved when animating ik_hand_r attached to PalmRight.
Press Х button to the right of a binding to remove it.