artisynth.core.inverse

Class InverseManager

java.lang.Object

artisynth.core.inverse.InverseManager

public class InverseManager
extends java.lang.Object

Helper class for creating probes and a control panel for use with a TrackingController. The two primary methods are

  addProbes (rootModel, controller, duration, interval)

  addInversePanel (rootModel, controller)
 

which create the probes or panel for the indicated controller and add them to the specified root model. The probes start at time 0 and extend for duration seconds, while interval specifies the update interval for the output probes. Specifying interval as -1 will cause the output probes to update at the current simulation sample rate. An additional method,

  resetProbes (rootModel, controller, duration, interval)
 

behaves identically to addProbes(artisynth.core.workspace.RootModel, artisynth.core.inverse.TrackingController, double, double), but also clears all existing probes first.

addProbes(artisynth.core.workspace.RootModel, artisynth.core.inverse.TrackingController, double, double) adds up to three input and three output probes to the timeline, each identified by an enumerated type InverseManager.ProbeID. The input probes are:

 TARGET_POSITIONS     # desired trajectory for all motion targets
 TARGET_FORCES        # desired trajectory for all constraint force targets
 INPUT_EXCITATIONS    # input excitations to used for forward simulation
 

TARGET_FORCES is added only if a force target term has been added to the controller. Applications can use the TARGET_POSITIONS and TARGET_FORCES probes to supply reference trajectories for the motion and constraint force targets; each supplies a vector controlling all the degrees of freedom for the motion and force targets. The INPUT_EXCITATIONS probe is disabled by default, but can be used to supply excitations to run a forward simulation to generate a reference trajectory that can be later tracked by the controller, as described below. Once created, the inout probes may be located within the root model using the method findInputProbe(artisynth.core.workspace.RootModel, artisynth.core.inverse.InverseManager.ProbeID), and data for them may be set using setInputProbeData(artisynth.core.workspace.RootModel, artisynth.core.inverse.InverseManager.ProbeID, double[], double).

The output probes are:

 TRACKED_POSITIONS    # current motion targets trajectory
 SOURCE_POSITIONS     # actual trajectory for all motion sources
 COMPUTED_EXCITATIONS # excitations computed by the inverse solver
 

The TRACKED_POSITIONS and COMPUTED_EXCITATIONS record the reference target positions and computed excitations as the inverse simulation proceeds, while SOURCE_POSITIONS records the actual resulting motion trajectory. Once created, these output probes may be located within the root model using the method findOutputProbe(artisynth.core.workspace.RootModel, java.lang.String).

Each probe is assigned a name and an attached file name based on converted its InverseManager.ProbeID name to lower case. For example, TARGET_POSITIONS is given the name "target positions" and attached file name "target_positions.txt". A probe's attached file name can be changed using setProbeFileName(artisynth.core.workspace.RootModel, artisynth.core.inverse.InverseManager.ProbeID, java.lang.String).

To generate a reference trajectory using a forward simulation, one should disable the tracking controller (by setting its enabled property to false), and then enable the INPUT_EXCITATIONS probe and use it to supply excitations to drive the underlying model. The resulting motion trajectory is stored in the SOURCE_POSITIONS probe. The contents of the SOURCE_POSITIONS probe can then be transferred to the TARGET_POSITIONS input probe, using the method syncTargetProbes(artisynth.core.workspace.RootModel), to be used as a control input for inverse simulation when the controller is reenabled. The ability of the controller to then follow the prescribed trajectory can then be used as a test of its capability. Likewise, the contents of the COMPUTED_EXCITATIONS probe can be transferred to the INPUT_EXCITATIONS probe using syncExcitationProbes(artisynth.core.workspace.RootModel).

The control panel created by addInversePanel(artisynth.core.workspace.RootModel, artisynth.core.inverse.TrackingController) allows a user to interactively adjust properties of the controller and its subcomponents, and provides three buttons (reset probes, sync excitations, and syncTargets) that call the methods resetProbes(artisynth.core.workspace.RootModel, artisynth.core.inverse.TrackingController, double, double), syncExcitationProbes(artisynth.core.workspace.RootModel), and syncTargetProbes(artisynth.core.workspace.RootModel).

Author:

Ian Stavness, John E Lloyd

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static class	InverseManager.InverseControlPanel
static class	InverseManager.ProbeID Identifiers for the probes created by this InverseManager

Field Summary

Fields

Modifier and Type	Field and Description
static boolean	useLegacyNames

Constructor Summary

Constructors

Constructor and Description
InverseManager()

Method Summary

Modifier and Type	Method and Description
static ControlPanel	addInversePanel(RootModel root, TrackingController controller) Creates a control panel for the specified inverse tracking controller, and then adds it to a root model and positions it to the side of the main frame.
static void	addProbes(RootModel root, TrackingController controller, double duration, double interval) Adds a set of input and output probes to a root model, for use in controlling inverse simulation.
static ControlPanel	createInversePanel(TrackingController controller) Creates a control panel for the specified inverse tracking controller.
static NumericInputProbe	findInputProbe(RootModel root, InverseManager.ProbeID pid) Searches for a specified input probe within a root model.
static TrackingController	findInverseController(RootModel root) Searches for an inverse controller within a root model.
static ControlPanel	findInversePanel(RootModel root) Searches for an inverse control panel within a root model.
static NumericOutputProbe	findOutputProbe(RootModel root, InverseManager.ProbeID pid) Searches for a specified output probe within a root model.
static Probe	findProbe(RootModel root, InverseManager.ProbeID pid) Searches for a specified probe within a root model.
static void	resetProbes(RootModel root, TrackingController controller, double duration, double interval) Clears all probes in a root model and then adds a set of probes for controlling the inverse simulation, as described for addProbes(artisynth.core.workspace.RootModel, artisynth.core.inverse.TrackingController, double, double).
static boolean	setInputProbeData(RootModel root, InverseManager.ProbeID pid, double[] data, double timeStep) Sets the data for a specified input probe within a root model, using the NumericInputProbe method NumericInputProbe.addData(java.io.File, double).
static boolean	setProbeFileName(RootModel root, InverseManager.ProbeID pid, java.lang.String name) Sets the attached file name for a specified probe within a root model.
static boolean	syncExcitationProbes(RootModel root) Locates the InverseManager.ProbeID.INPUT_EXCITATIONS probe and InverseManager.ProbeID.COMPUTED_EXCITATIONS probe within a root model and copies the contents of the latter to the former.
static boolean	syncTargetProbes(RootModel root) Locates the InverseManager.ProbeID.TARGET_POSITIONS probe and InverseManager.ProbeID.SOURCE_POSITIONS probe within a root model and copies the contents of the latter to the former.

Methods inherited from class java.lang.Object

equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

useLegacyNames

public static boolean useLegacyNames

Constructor Detail

InverseManager

public InverseManager()

Method Detail

findInverseController

public static TrackingController findInverseController(RootModel root)

Searches for an inverse controller within a root model. If it is not found, returns null.

Parameters:

root - root model in which to search for the controller

Returns:

located inverse controller, or null

createInversePanel

public static ControlPanel createInversePanel(TrackingController controller)

Creates a control panel for the specified inverse tracking controller.

Parameters:

controller - controller to create the panel for

Returns:

created control panel

addInversePanel

public static ControlPanel addInversePanel(RootModel root,
                                           TrackingController controller)

Creates a control panel for the specified inverse tracking controller, and then adds it to a root model and positions it to the side of the main frame.

Parameters:

controller - controller to create the panel for

root - root model to add the panel to

Returns:

created control panel

findInversePanel

public static ControlPanel findInversePanel(RootModel root)

Searches for an inverse control panel within a root model. If it is not found, returns null.

Parameters:

root - root model in which to search for the panel

Returns:

located inverse panel, or null

addProbes

public static void addProbes(RootModel root,
                             TrackingController controller,
                             double duration,
                             double interval)

Adds a set of input and output probes to a root model, for use in controlling inverse simulation. A description of the created probes is given in the documentation header for this class. The probes start at time 0 and stop at the time indicated by duration. The output probes are updated at the specified interval; if specified as -1, then the output probes are updated at the current simulation sample rate.

Parameters:

root - root model to which the probes should be added

controller - inverse controller for which the probes should be created

duration - time duration for each probe

interval - update interval for the output probes

findOutputProbe

public static NumericOutputProbe findOutputProbe(RootModel root,
                                                 InverseManager.ProbeID pid)

Searches for a specified output probe within a root model. If it is not found, returns null.

Parameters:

root - root model in which to search for the probe

pid - probe identifier

Returns:

located probe, or null

findProbe

public static Probe findProbe(RootModel root,
                              InverseManager.ProbeID pid)

Searches for a specified probe within a root model. If it is not found, returns null.

Parameters:

root - root model in which to search for the probe

pid - probe identifier

Returns:

located probe, or null

findInputProbe

public static NumericInputProbe findInputProbe(RootModel root,
                                               InverseManager.ProbeID pid)

Searches for a specified input probe within a root model. If it is not found, returns null.

Parameters:

root - root model in which to search for the probe

pid - probe identifier

Returns:

located probe, or null

setProbeFileName

public static boolean setProbeFileName(RootModel root,
                                       InverseManager.ProbeID pid,
                                       java.lang.String name)

Sets the attached file name for a specified probe within a root model. The method searches for the probe, and if it doesn't find it, returns false.

Parameters:

root - root model in which to search for the probe

pid - probe identifier

Returns:

true if the probe was found and the file was renamed

setInputProbeData

public static boolean setInputProbeData(RootModel root,
                                        InverseManager.ProbeID pid,
                                        double[] data,
                                        double timeStep)

Sets the data for a specified input probe within a root model, using the NumericInputProbe method NumericInputProbe.addData(java.io.File, double). The probe is also set be ``active'', and its interpolation order is set to CubicStep. The method searches for the probe, and if it doesn't find it, returns false.

Parameters:

root - root model in which to search for the probe

pid - probe identifier

data - array specifiying the input data

timeStep - time step associated with the data; if set to NumericProbeBase.EXPLICIT_TIME, the times are set explicitly within the data

Returns:

true if the probe was found and the data was set

syncTargetProbes

public static boolean syncTargetProbes(RootModel root)

Locates the InverseManager.ProbeID.TARGET_POSITIONS probe and InverseManager.ProbeID.SOURCE_POSITIONS probe within a root model and copies the contents of the latter to the former. If either probe is not found, the method does nothing and returns false.

Parameters:

root - root model in which probes should be located

Returns:

true if the probes were found and synchronized

syncExcitationProbes

public static boolean syncExcitationProbes(RootModel root)

Locates the InverseManager.ProbeID.INPUT_EXCITATIONS probe and InverseManager.ProbeID.COMPUTED_EXCITATIONS probe within a root model and copies the contents of the latter to the former. If either probe is not found, the method does nothing and returns false.

Parameters:

root - root model in which probes should be located

Returns:

true if the probes were found and synchronized

resetProbes

public static void resetProbes(RootModel root,
                               TrackingController controller,
                               double duration,
                               double interval)

Clears all probes in a root model and then adds a set of probes for controlling the inverse simulation, as described for addProbes(artisynth.core.workspace.RootModel, artisynth.core.inverse.TrackingController, double, double).

Parameters:

root - root model to which the probes should be added

controller - inverse controller for which the probes should be created

duration - time duration for each probe

interval - update interval for the output probes