Defines the parameters of the Walking Pattern Generator. More...

#include <WMG.h>

Public Member Functions
	WMG (const unsigned int, const unsigned int, const double step_height_=0.0135, double bezier_weight_1_=1.0, double bezier_weight_2_=2.0, double bezier_inclination_1_=0.01, double bezier_inclination_2_=0.008)
	Initializes a WMG object.
	~WMG ()
	Default destructor.
void	setFootstepDefaults (const unsigned int, const unsigned int, const double *constraints=NULL)
	Set default parameters of footsteps.
void	setFootstepDefaults (const unsigned int, const unsigned int, const unsigned int, const double *constraints=NULL)
	Set default parameters of footsteps.
void	addFootstep (const double, const double, const double, fs_type type=FS_TYPE_AUTO)
	Adds a footstep to FS.
bool	isSupportSwitchNeeded ()
	Checks if the support foot switch is needed.
WMGret	formPreviewWindow (smpc_parameters &)
	Forms a preview window.
void	FS2file (const std::string, const bool plot_ds=true)
	Outputs the footsteps in FS to a file, that can be executed in Matlab/Octave to get a figure of the steps.
void	getFeetPositions (const unsigned int, double , double )
	Determine position and orientation of feet.
void	getFootsteps (std::vector< double > &, std::vector< double > &, std::vector< double > &)
	Return coordinates of footstep reference points and rotation angles of footsteps (only for SS).
void	changeNextSSPosition (const double *, const bool)
	Changes position of the next SS.
Public Attributes
std::vector< footstep >	FS
	A vector of footsteps.
unsigned int	N
	Number of iterations in a preview window.
unsigned int *	T_ms
unsigned int	sampling_period
int	current_step_number
int	first_preview_step
	The first step in the current preview window.
double	step_height
	The maximum height, that can be reached by a swing foot.
double	def_ss_constraint [4]
double	def_auto_ds_constraint [4]

double	bezier_weight_1
double	bezier_weight_2
double	bezier_inclination_1
double	bezier_inclination_2
Private Member Functions
void	getDSFeetPositions (const int, double , double )
	Determine position and orientation of feet in DS.
void	getSSFeetPositions (const int, const double, double , double )
	Determine position and orientation of feet (parabolic trajectory)
void	getSSFeetPositionsBezier (const int, const double, double , double )
	Determine position and orientation of feet (using cubic Bezier curves)
int	getNextSS (const int, const fs_type type=FS_TYPE_AUTO)
	Returns index of the next SS.
int	getPrevSS (const int, const fs_type type=FS_TYPE_AUTO)
	Returns index of the previous SS.
Private Attributes
double	addstep_constraint [4]
unsigned int	def_time_ms
unsigned int	ds_time_ms
unsigned int	ds_num
unsigned int	last_time_decrement

Detailed Description

Defines the parameters of the Walking Pattern Generator.

Definition at line 120 of file WMG.h.

Constructor & Destructor Documentation

WMG::WMG	(	const unsigned int	N_,
		const unsigned int	T_,
		const double	step_height_ = `0.0135`,
		double	bezier_weight_1_ = `1.0`,
		double	bezier_weight_2_ = `2.0`,
		double	bezier_inclination_1_ = `0.01`,
		double	bezier_inclination_2_ = `0.008`
	)

Initializes a WMG object.

Parameters:

[in]	N_	Number of sampling times in a preview window
[in]	T_	Sampling time [ms.]
[in]	step_height_	step height (for interpolation of feet movements) [meter]
[in]	bezier_weight_1_	see bezier_weight_1
[in]	bezier_weight_2_	see bezier_weight_2
[in]	bezier_inclination_1_	see bezier_inclination_1
[in]	bezier_inclination_2_	see bezier_inclination_2

NAO constraint with safety margin.

Definition at line 27 of file WMG.cpp.

WMG::~WMG ( )

Default destructor.

Definition at line 79 of file WMG.cpp.

Member Function Documentation

void WMG::addFootstep	(	const double	x_relative,
		const double	y_relative,
		const double	angle_relative,
		fs_type	type = `FS_TYPE_AUTO`
	)

Adds a footstep to FS.

Parameters:

[in]	x_relative	x_relative X position [meter] relative to the previous footstep.
[in]	y_relative	y_relative Y position [meter] relative to the previous footstep.
[in]	angle_relative	angle_relative Angle [rad.] relative to the previous footstep.
[in]	type	(optional) type of the footstep.

Note:: Coordinates and angle are treated as absolute for the first step in the preview window.

Definition at line 157 of file WMG.cpp.

void WMG::changeNextSSPosition	(	const double *	posture,
		const bool	zero_z_coordinate
	)

Changes position of the next SS.

Parameters:

[in]	posture	a 4x4 homogeneous matrix representing new position and orientation
[in]	zero_z_coordinate	set z coordinate to 0.0

Todo:: DS must be adjusted as well.

Definition at line 356 of file WMG.cpp.

WMGret WMG::formPreviewWindow ( smpc_parameters & par )

Forms a preview window.

Returns:: WMG_OK or WMG_HALT (simulation must be stopped)

Definition at line 368 of file WMG.cpp.

void WMG::FS2file	(	const std::string	filename,
		const bool	plot_ds = `true`
	)

Outputs the footsteps in FS to a file, that can be executed in Matlab/Octave to get a figure of the steps.

Parameters:

[in]	filename	output file name.
[in]	plot_ds	enable/disable plotting of double supports

Definition at line 467 of file WMG.cpp.

void WMG::getDSFeetPositions	(	const int	support_number,
		double *	left_foot_pos,
		double *	right_foot_pos
	)		`[private]`

Determine position and orientation of feet in DS.

Parameters:

[in]	support_number	number of the support
[out]	left_foot_pos	4x4 homogeneous matrix, which represents position and orientation
[out]	right_foot_pos	4x4 homogeneous matrix, which represents position and orientation

Definition at line 90 of file WMG_private.cpp.

void WMG::getFeetPositions	(	const unsigned int	shift_from_current_ms,
		double *	left_foot_pos,
		double *	right_foot_pos
	)

Determine position and orientation of feet.

Parameters:

[in]	shift_from_current_ms	a positive shift in time (ms.) from the current time (allows to get positions for the future supports)
[out]	left_foot_pos	4x4 homogeneous matrix, which represents position and orientation
[out]	right_foot_pos	4x4 homogeneous matrix, which represents position and orientation

Attention:: This function requires the walking pattern to be started and finished by single support.; Cannot be called on the first or last SS => must be called after FormPreviewWindow().

Definition at line 273 of file WMG.cpp.

void WMG::getFootsteps	(	std::vector< double > &	x_coord,
		std::vector< double > &	y_coord,
		std::vector< double > &	angle_rot
	)

Return coordinates of footstep reference points and rotation angles of footsteps (only for SS).

Parameters:

[out]	x_coord	x coordinates
[out]	y_coord	y coordinates
[out]	angle_rot	angles

Definition at line 540 of file WMG.cpp.

int WMG::getNextSS	(	const int	start_ind,
		const fs_type	type = `FS_TYPE_AUTO`
	)		`[private]`

Returns index of the next SS.

Parameters:

[in]	start_ind	start search from this index.
[in]	type	search for a footstep of certain type, by default (FS_TYPE_AUTO) both left and right are searched.

Returns:: index of the next SS.

Definition at line 23 of file WMG_private.cpp.

int WMG::getPrevSS	(	const int	start_ind,
		const fs_type	type = `FS_TYPE_AUTO`
	)		`[private]`

Returns index of the previous SS.

Parameters:

[in]	start_ind	start search from this index.
[in]	type	search for a footstep of certain type, by default (FS_TYPE_AUTO) both left and right are searched.

Returns:: index of the previous SS.

Definition at line 58 of file WMG_private.cpp.

void WMG::getSSFeetPositions	(	const int	support_number,
		const double	theta,
		double *	left_foot_pos,
		double *	right_foot_pos
	)		`[private]`

Determine position and orientation of feet (parabolic trajectory)

Parameters:

[in]	support_number	number of the support
[in]	theta	a number between 0 and 1, a fraction of support time that have passed
[out]	left_foot_pos	4x4 homogeneous matrix, which represents position and orientation
[out]	right_foot_pos	4x4 homogeneous matrix, which represents position and orientation

Definition at line 122 of file WMG_private.cpp.

void WMG::getSSFeetPositionsBezier	(	const int	support_number,
		const double	theta,
		double *	left_foot_pos,
		double *	right_foot_pos
	)		`[private]`

Determine position and orientation of feet (using cubic Bezier curves)

Parameters:

[in]	support_number	number of the support
[in]	theta	a number between 0 and 1, a fraction of support time that have passed
[out]	left_foot_pos	4x4 homogeneous matrix, which represents position and orientation
[out]	right_foot_pos	4x4 homogeneous matrix, which represents position and orientation

Definition at line 184 of file WMG_private.cpp.

bool WMG::isSupportSwitchNeeded ( )

Checks if the support foot switch is needed.

Returns:: true if the support foot must be switched.

Definition at line 321 of file WMG.cpp.

void WMG::setFootstepDefaults	(	const unsigned int	def_num_,
		const unsigned int	ds_num_,
		const double *	constraints = `NULL`
	)

Set default parameters of footsteps.

Parameters:

[in]	def_num_	default time in ms (for SS or DS depending on the type of added footstep)
[in]	ds_num_	number of DS to be generated automatically.
[in]	constraints	Vector of the PoS constraints (assumed to be [4 x 1], can be NULL).

Note:: length of one automatically generated DS is assumed to be equal to sampling_period.

Definition at line 98 of file WMG.cpp.

void WMG::setFootstepDefaults	(	const unsigned int	def_time_ms_,
		const unsigned int	ds_time_ms_,
		const unsigned int	ds_num_,
		const double *	constraints = `NULL`
	)

Set default parameters of footsteps.

Parameters:

[in]	def_time_ms_	default time in ms (for SS or DS depending on the type of added footstep)
[in]	ds_time_ms_	length of one automatically generated DS [ms.]
[in]	ds_num_	number of DS to be generated automatically.
[in]	constraints	Vector of the PoS constraints (assumed to be [4 x 1], can be NULL).

Definition at line 126 of file WMG.cpp.

Member Data Documentation

double WMG::addstep_constraint[4] [private]

Definition at line 223 of file WMG.h.

double WMG::bezier_inclination_1

The foot trajectories, that are build using Bezier curve have four control points (0,1,3,4). The first and the last points are defined by positions of adjacent steps of a foot on the floor. The 1 and 2 points are computed depending on the given parameters.

The step height is fixed in the middle (theta = 0.5) of the step, note, that this is not the geometrical middle.

The control points have weights, the weights of the first and the last points are always equal to 1.0. The weights of other two points can be given by the user.

The 1 and 2 points also have inclination, i.e. the shift along y axis (in the frame fixed in the step reference point). The values of inclinations are given in meters.

Definition at line 211 of file WMG.h.

double WMG::bezier_inclination_2

The foot trajectories, that are build using Bezier curve have four control points (0,1,3,4). The first and the last points are defined by positions of adjacent steps of a foot on the floor. The 1 and 2 points are computed depending on the given parameters.

The step height is fixed in the middle (theta = 0.5) of the step, note, that this is not the geometrical middle.

The control points have weights, the weights of the first and the last points are always equal to 1.0. The weights of other two points can be given by the user.

The 1 and 2 points also have inclination, i.e. the shift along y axis (in the frame fixed in the step reference point). The values of inclinations are given in meters.

Definition at line 212 of file WMG.h.

double WMG::bezier_weight_1

The foot trajectories, that are build using Bezier curve have four control points (0,1,3,4). The first and the last points are defined by positions of adjacent steps of a foot on the floor. The 1 and 2 points are computed depending on the given parameters.

The step height is fixed in the middle (theta = 0.5) of the step, note, that this is not the geometrical middle.

The control points have weights, the weights of the first and the last points are always equal to 1.0. The weights of other two points can be given by the user.

The 1 and 2 points also have inclination, i.e. the shift along y axis (in the frame fixed in the step reference point). The values of inclinations are given in meters.

Definition at line 209 of file WMG.h.

double WMG::bezier_weight_2

The foot trajectories, that are build using Bezier curve have four control points (0,1,3,4). The first and the last points are defined by positions of adjacent steps of a foot on the floor. The 1 and 2 points are computed depending on the given parameters.

The step height is fixed in the middle (theta = 0.5) of the step, note, that this is not the geometrical middle.

The control points have weights, the weights of the first and the last points are always equal to 1.0. The weights of other two points can be given by the user.

The 1 and 2 points also have inclination, i.e. the shift along y axis (in the frame fixed in the step reference point). The values of inclinations are given in meters.

Definition at line 210 of file WMG.h.

int WMG::current_step_number

This is the step in FS that is at the start of the current preview window.

Definition at line 180 of file WMG.h.

double WMG::def_auto_ds_constraint[4]

Definition at line 189 of file WMG.h.

double WMG::def_ss_constraint[4]

Definition at line 188 of file WMG.h.

unsigned int WMG::def_time_ms [private]

Definition at line 225 of file WMG.h.

unsigned int WMG::ds_num [private]

Definition at line 227 of file WMG.h.