The topics covered in this section include:
How to Use the GUI
To launch the IK Tool:
Select Tools → Inverse Kinematics from the OpenSim main menu bar.
The Settings pane is used to specify parameters related to the experimental marker data. The Weights pane is used to specify the marker and coordinate weights used in the weighted least squares equation.
The Inverse Kinematics Tool window, like all other OpenSim tools, operates on the current model. The name of the current model is shown in bold in the Navigator window. Any model can be made the current model by right-clicking on its name and selecting Make Current. See Opening, Closing, and Using the Navigator Window for information on opening models and making a particular model current.
The Control Panel
At the bottom of all the Tool dialog windows are four buttons, located in what we call the Control Panel.
Note that the Close button can be clicked immediately after execution has begun; the execution will complete even though the window has been closed.
The Settings pane is used to specify parameters related to the experimental marker data. The pane is organized into two main sections: Current Model and IK Trial.
Once a marker and possibly a coordinate file have been specified, the specific behavior of the inverse kinematics tool can be described and modified using the Weights pane (Figure below). Each entry in the table represents a task in the least-squares matching for either a marker (top table) or a coordinate (lower table). By left-clicking on a row, you select it, making the entry fields below the tables editable so you can specify weights and values for the selected marker(s) or coordinate(s). You can select multiple rows to edit by using ctrl + left-mouse-click or shift + left-mouse-click.
When running the IK Tool using the GUI, the results are not automatically saved to a file. They are associated with the model under its Motions node in the Navigator window (Navigator Window). You can view multiple IK results before saving them to a file. To save the IK results to a file, right click on the motion in the Navigator window and select Save as.
The Control Panel
The control panel at the bottom of the dialog window is used to save the settings in the dialog to a file, read the settings from a file, and to run IK. It has the same behavior as described in Scale Setup File
Command Line Execution of IK
The Inverse Kinematics Tool is run using the command ik -S <setup file name>, for example: