Description
The squared difference between a control variable value and a reference control variable value, summed over the control variables for which a reference is provided, and integrated over the phase.
This can be used to track actuator controls, muscle excitations, etc.
This goal is computed as follows:
\[ \int_{t_i}^{t_f} \sum_{c \in C} w_c \|x_{m,c}(t) - x_{e,c})\|^2 ~dt \]
We use the following notation:
- \( t_i \): the initial time of this phase.
- \( t_f \): the final time of this phase.
- \( C \): the set of control variables being tracked.
- \( w_c \): the weight for control \( c \).
- \( x_{m,c}(t) \): control signal \( c \).
- \( x_{e,c}(t) \): reference data for control signal \( c \).
This goal has two labeling modes: 'auto' and 'manual':
- 'auto': The column labels of the reference must exactly match the names of controls, and all controls with a matching column in the reference data are tracked. By default, all column labels for the reference data must match the name of a control. Setting
allow_unused_referencesto false allows the reference to contain columns whose labels do not match a control; such columns are then ignored. - 'manual': The association between controls and columns of the reference data is manually specified via the
reference_labelsproperty. Only the controls for which a reference label is specified are tracked. Enter this mode by providing reference labels through thereference_labelsproperty or thesetReferenceLabel()function. Theallow_unused_referencesproperty does not apply in this mode.
Control variable names
Control variable names are based on paths to actuators, e.g., /forceset/soleus_r. For non-scalar actuators, the control variable name includes the index for the actuator control; e.g., /forceset/body_actuator_0, where 'body_actuator' is the name of the actuator and _0 specifies the control index.
Reference data
The reference can be provided as a file name to a STO or CSV file (or other file types for which there is a FileAdapter), or programmatically as a TimeSeriesTable.
Helpful tips
Tracking problems in direct collocation perform best when tracking smooth data, so it is recommended to filter the data in the reference you provide to the cost.
- Examples:
- exampleMocoInverse.cpp.
#include <Moco/Moco/MocoGoal/MocoControlTrackingGoal.h>
Public Member Functions | |
| MocoControlTrackingGoal (std::string name) | |
| MocoControlTrackingGoal (std::string name, double weight) | |
| void | setReference (const TableProcessor &ref) |
| Provide a table containing reference values for the controls you want to track. More... | |
| void | setWeightForControl (const std::string &controlName, const double &weight) |
| Set the weight for an individual control variable. More... | |
| void | setWeightSet (const MocoWeightSet &weightSet) |
| Provide a MocoWeightSet to weight the control variables in the cost. More... | |
| void | setReferenceLabel (const std::string &control, const std::string &label) |
| Set the column of the reference data that a given control should track. More... | |
| void | clearReferenceLabels () |
| Clear the 'reference_labels' property, which ensures this goal is used in 'auto' labeling mode. More... | |
| void | setAllowUnusedReferences (bool tf) |
| Specify whether the reference can have columns not associated with controls. More... | |
| const TableProcessor & | getReference () const |
| If no reference has been provided, this returns an empty processor. | |
| bool | hasReferenceLabel (const std::string &control) const |
| std::string | getReferenceLabel (const std::string &control) const |
| bool | getAllowUnusedReferences () const |
 Public Member Functions inherited from OpenSim::MocoGoal | |
| MocoGoal (std::string name) | |
| MocoGoal (std::string name, double weight) | |
| void | setEnabled (bool enabled) |
| Set whether this goal is used in the problem. | |
| bool | getEnabled () const |
| void | setWeight (double weight) |
| In cost mode, the goal is multiplied by this weight. More... | |
| double | getWeight () const |
| void | setMode (std::string mode) |
| Set the mode property to either 'cost' or 'endpoint_constraint'. More... | |
| std::string | getModeAsString () const |
| This returns the default mode of the goal, unless the user overrode the default using setMode(). More... | |
| Mode | getMode () const |
| bool | getModeIsCost () const |
| bool | getModeIsEndpointConstraint () const |
| Mode | getDefaultMode () const |
| Types of goals have a class-level default for whether they are enforced as a cost or endpoint constraint. More... | |
| bool | getSupportsEndpointConstraint () const |
| Can this constraint be used in endpoint constraint mode? | |
| const MocoConstraintInfo & | getConstraintInfo () const |
| Get bounds for the constraints when using this goal in endpoint constraint mode. More... | |
| MocoConstraintInfo & | updConstraintInfo () |
| int | getNumOutputs () const |
| Get the length of the return value of calcGoal(). | |
| int | getNumIntegrals () const |
| Get the number of integrals required by this cost. More... | |
| SimTK::Real | calcIntegrand (const SimTK::State &state) const |
| Calculate the integrand that should be integrated and passed to calcCost(). More... | |
| void | calcGoal (const GoalInput &input, SimTK::Vector &goal) const |
| In cost mode, the returned cost includes the weight, and the elements of the returned vector should be summed by the caller to obtain the total cost. More... | |
| void | initializeOnModel (const Model &model) const |
| For use by solvers. This also performs error checks on the Problem. | |
| void | printDescription (std::ostream &stream=std::cout) const |
| Print the name type and mode of this goal. More... | |
Protected Member Functions | |
| void | initializeOnModelImpl (const Model &model) const override |
| Perform any caching before the problem is solved. More... | |
| void | calcIntegrandImpl (const SimTK::State &state, double &integrand) const override |
| void | calcGoalImpl (const GoalInput &input, SimTK::Vector &cost) const override |
| The Lagrange multipliers for kinematic constraints are not available. | |
| void | printDescriptionImpl (std::ostream &stream=std::cout) const override |
| Print a more detailed description unique to each goal. | |
| Protected Member Functions inherited from OpenSim::MocoGoal | |
| void | setNumIntegralsAndOutputs (int numIntegrals, int numOutputs) const |
| Set the number of integral terms required by this goal and the length of the vector passed into calcGoalImpl(). More... | |
| virtual Mode | getDefaultModeImpl () const |
| virtual bool | getSupportsEndpointConstraintImpl () const |
| const Model & | getModel () const |
| For use within virtual function implementations. | |
| double | calcSystemDisplacement (const SimTK::State &initial, const SimTK::State &final) const |
Additional Inherited Members | |
| Public Types inherited from OpenSim::MocoGoal | |
| enum | Mode { Cost, EndpointConstraint } |
Member Function Documentation
◆ calcIntegrandImpl()
|
overrideprotectedvirtual |
- Precondition(s):
- The state is realized to SimTK::Stage::Position. If you need access to the controls, you must realize to Velocity: The Lagrange multipliers for kinematic constraints are not available.getModel().realizeVelocity(state);
Reimplemented from OpenSim::MocoGoal.
◆ clearReferenceLabels()
|
inline |
Clear the 'reference_labels' property, which ensures this goal is used in 'auto' labeling mode.
◆ initializeOnModelImpl()
|
overrideprotectedvirtual |
Perform any caching before the problem is solved.
You must override this function and invoke setNumIntegralsAndOutputs().
- Precondition(s):
- The model is initialized (initSystem()) and getModel() is available. The passed-in model is equivalent to getModel(). Use this opportunity to check for errors in user input.
Implements OpenSim::MocoGoal.
◆ setAllowUnusedReferences()
|
inline |
Specify whether the reference can have columns not associated with controls.
If set true, then such columns will be ignored by the cost. If false, such columns will cause an Exception to be raised. Only takes effect in 'auto' labeling mode.
◆ setReference()
|
inline |
Provide a table containing reference values for the controls you want to track.
In 'auto' labeling mode, each column label must be a control variable name. In 'manual' labeling mode, the column labels need not be control variable names; use setReferenceLabel() to associate controls with columns. The table is not loaded until the MocoProblem is initialized.
◆ setReferenceLabel()
|
inline |
Set the column of the reference data that a given control should track.
Multiple controls can track the same column of the reference data. This replaces the reference label for the given control, if one had already been provided. If controls are not manually associated with a reference label, then it is assumed that the column labels for the reference data exactly match the names of controls.
◆ setWeightForControl()
|
inline |
Set the weight for an individual control variable.
If a weight is already set for the requested control, then the provided weight replaces the previous weight. If no weight is specified for a control, a weight of 1.0 is used internally. Set the weight to 0 to avoid tracking a given control. An exception is thrown if a weight for an unknown control is provided.
◆ setWeightSet()
|
inline |
Provide a MocoWeightSet to weight the control variables in the cost.
Replaces the weight set if it already exists.
The documentation for this class was generated from the following file: