towr::PhaseDurations Class Reference

A variable set composed of the phase durations of an endeffector. More...

#include <phase_durations.h>

List of all members.

Public Member Functions
void	AddObserver (PhaseDurationsObserver *const spline)
	Adds observer that is updated every time new variables are set.
VecBound	GetBounds () const override
Jacobian	GetJacobianOfPos (int phase, const VectorXd &dx_dT, const VectorXd &xd) const
	How a change in the phase durations affect the position of a spline.
VecDurations	GetPhaseDurations () const
VectorXd	GetValues () const override
bool	IsContactPhase (double t) const
	Whether the endeffector is in contact with the environment.
	PhaseDurations (EndeffectorID ee, const VecDurations &initial_durations, bool is_first_phase_in_contact, double min_phase_duration, double max_phase_duration)
	Constructs a variable set for a specific endeffector.
void	SetVariables (const VectorXd &x) override
	Sets the phase durations from pure Eigen optimization variables.
virtual	~PhaseDurations ()
Private Member Functions
void	UpdateObservers () const
Private Attributes
VecDurations	durations_
bool	initial_contact_state_
	true if first phase in contact
std::vector < PhaseDurationsObserver * >	observers_
ifopt::Bounds	phase_duration_bounds_
double	t_total_

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Detailed Description

A variable set composed of the phase durations of an endeffector.

This class holds the current variables determining the alternating swing- and stance durations of one foot. These durations are then used in the Spline together with NodeVariables to construct foot motions and forces.

See this explanation: https://youtu.be/KhWuLvb934g?t=788

Definition at line 50 of file phase_durations.h.

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Constructor & Destructor Documentation

towr::PhaseDurations::PhaseDurations	(	EndeffectorID	ee,
		const VecDurations &	initial_durations,
		bool	is_first_phase_in_contact,
		double	min_phase_duration,
		double	max_phase_duration
	)

Constructs a variable set for a specific endeffector.

Parameters:

ee	The endeffector ID which these durations apply to.
initial_durations	Initial values for the optimization variables.
min_phase_duration	The minimum allowable time for one phase.
max_phase_duration	The maximum allowable time for one phase.

Definition at line 41 of file phase_durations.cc.

virtual towr::PhaseDurations::~PhaseDurations

(

)

[virtual]

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Member Function Documentation

void towr::PhaseDurations::AddObserver

(

PhaseDurationsObserver *const

spline

)

Adds observer that is updated every time new variables are set.

Parameters:

spline

A pointer to a Hermite spline using the durations.

Definition at line 56 of file phase_durations.cc.

PhaseDurations::VecBound towr::PhaseDurations::GetBounds

(

)

const [override]

Returns:

The maximum and minimum time each phase is allowed to take.

Definition at line 103 of file phase_durations.cc.

PhaseDurations::Jacobian towr::PhaseDurations::GetJacobianOfPos	(	int	phase,
		const VectorXd &	dx_dT,
		const VectorXd &	xd
	)		const

How a change in the phase durations affect the position of a spline.

Parameters:

phase	The current phase the spline is in at time t.
dx_dT	The derivative of the spline position w.r.t the phase durations T.
xd	The velocity of the spline at the current time t.

Returns:

A pxn dimensional Jacobian where: p: number of dimensions of the spline (e.g. x,y,z) n: number of phase durations in this class that are optimized over.

This method is related to constructing a cubic-Hermite spline with these phase durations. Leaving the node values unchanged, the shape of the spline can also be changed by expanding or compressing the individual polynomials through the duration. This method quantifies the sensitivity of the spline position on these durations.

Definition at line 127 of file phase_durations.cc.

PhaseDurations::VecDurations towr::PhaseDurations::GetPhaseDurations

(

)

const

Returns:

The durations (stance, swing, ...) for each phase of this foot.

Definition at line 114 of file phase_durations.cc.

Eigen::VectorXd towr::PhaseDurations::GetValues

(

)

const [override]

Returns:

The optimization variables (phase durations [s]).

Definition at line 69 of file phase_durations.cc.

bool towr::PhaseDurations::IsContactPhase

(

double

t

)

const

Whether the endeffector is in contact with the environment.

Parameters:

t	global time along the trajectory.

Definition at line 120 of file phase_durations.cc.

void towr::PhaseDurations::SetVariables

(

const VectorXd &

x

)

[override]

Sets the phase durations from pure Eigen optimization variables.

Definition at line 80 of file phase_durations.cc.

void towr::PhaseDurations::UpdateObservers

(

)

const [private]

Definition at line 62 of file phase_durations.cc.

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Member Data Documentation

VecDurations towr::PhaseDurations::durations_ [private]

Definition at line 121 of file phase_durations.h.

bool towr::PhaseDurations::initial_contact_state_ [private]

true if first phase in contact

Definition at line 124 of file phase_durations.h.

std::vector<PhaseDurationsObserver*> towr::PhaseDurations::observers_ [private]

Definition at line 127 of file phase_durations.h.

ifopt::Bounds towr::PhaseDurations::phase_duration_bounds_ [private]

Definition at line 125 of file phase_durations.h.

double towr::PhaseDurations::t_total_ [private]

Definition at line 123 of file phase_durations.h.

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The documentation for this class was generated from the following files:

• phase_durations.h
• phase_durations.cc