kinematics.hpp File Reference

Contains functions for computing various kinematic quantities of a tinyrobotics model. More...

#include <Eigen/Core>
#include <Eigen/Geometry>
#include "math.hpp"
#include "model.hpp"

Go to the source code of this file.

Functions
template<typename Scalar , int nq, typename TargetLink >
int	tinyrobotics::get_link_idx (const Model< Scalar, nq > &model, const TargetLink &target_link)
	Retrieves the index of the target link in the tinyrobotics model.
template<typename Scalar , int nq>
std::vector< Eigen::Transform< Scalar, 3, Eigen::Isometry > >	tinyrobotics::forward_kinematics (Model< Scalar, nq > &model, const Eigen::Matrix< Scalar, nq, 1 > &q)
	Computes the transform to all the links in the tinyrobotics model.
template<typename Scalar , int nq, typename TargetLink >
Eigen::Transform< Scalar, 3, Eigen::Isometry >	tinyrobotics::forward_kinematics (const Model< Scalar, nq > &model, const Eigen::Matrix< Scalar, nq, 1 > &q, const TargetLink &target_link)
	Computes the transform between target and the base link. The transform converts points in target frame to the base link frame.
template<typename Scalar , int nq, typename TargetLink , typename SourceLink >
Eigen::Transform< Scalar, 3, Eigen::Isometry >	tinyrobotics::forward_kinematics (const Model< Scalar, nq > &model, const Eigen::Matrix< Scalar, nq, 1 > &q, const TargetLink &target_link, const SourceLink &source_link)
	Computes the transform between target and the source link. The transform converts points in target frame to the source link frame.
template<typename Scalar , int nq>
std::vector< Eigen::Transform< Scalar, 3, Eigen::Isometry > >	tinyrobotics::forward_kinematics_com (Model< Scalar, nq > &model, const Eigen::Matrix< Scalar, nq, 1 > &q)
	Computes the transform between center of mass of each link and the source link.
template<typename Scalar , int nq, typename TargetLink , typename SourceLink = int>
Eigen::Transform< Scalar, 3, Eigen::Isometry >	tinyrobotics::forward_kinematics_com (const Model< Scalar, nq > &model, const Eigen::Matrix< Scalar, nq, 1 > &q, const TargetLink &target_link, const SourceLink &source_link=0)
	Computes the transform between source link and target center of mass. The transform converts points in the target links center of mass frame into the source link frame.
template<typename Scalar , int nq, typename TargetLink >
Eigen::Matrix< Scalar, 6, nq >	tinyrobotics::jacobian (Model< Scalar, nq > &model, const Eigen::Matrix< Scalar, nq, 1 > &q, const TargetLink &target_link)
	Computes the geometric jacobian of the target link from the base link, in the base link frame.
template<typename Scalar , int nq, typename SourceLink = int>
Eigen::Matrix< Scalar, 3, 1 >	tinyrobotics::center_of_mass (Model< Scalar, nq > &model, const Eigen::Matrix< Scalar, nq, 1 > &q, const SourceLink &source_link=0)
	Computes the center of mass expressed in source link frame.

Detailed Description

Contains functions for computing various kinematic quantities of a tinyrobotics model.

Function Documentation

center_of_mass()

template<typename Scalar , int nq, typename SourceLink = int>

Eigen::Matrix< Scalar, 3, 1 > tinyrobotics::center_of_mass	(	Model< Scalar, nq > &	model,
		const Eigen::Matrix< Scalar, nq, 1 > &	q,
		const SourceLink &	source_link = 0
	)

Computes the center of mass expressed in source link frame.

Parameters

model	tinyrobotics model.
q	The configuration vector of the robot model.
source_link	Source link, which can be an integer (index) or a string (name), from which the center of mass is expressed.

Template Parameters

Scalar	type of the tinyrobotics model.
nq	Number of configuration coordinates (degrees of freedom).
SourceLink	Type of source_link parameter, which can be int or std::string.

Returns

The center of mass position expressed in source link frame.

forward_kinematics() [1/3]

template<typename Scalar , int nq, typename TargetLink >

Eigen::Transform< Scalar, 3, Eigen::Isometry > tinyrobotics::forward_kinematics	(	const Model< Scalar, nq > &	model,
		const Eigen::Matrix< Scalar, nq, 1 > &	q,
		const TargetLink &	target_link
	)

Computes the transform between target and the base link. The transform converts points in target frame to the base link frame.

Parameters

model	tinyrobotics model.
q	Joint configuration of the robot.
target_link	Target link, which can be an integer (index) or a string (name).

Template Parameters

Scalar	type of the tinyrobotics model.
nq	Number of configuration coordinates (degrees of freedom).
TargetLink	Type of target_link parameter, which can be int or std::string.

Returns

Homogeneous transform between the target and the base link.

forward_kinematics() [2/3]

template<typename Scalar , int nq, typename TargetLink , typename SourceLink >

Eigen::Transform< Scalar, 3, Eigen::Isometry > tinyrobotics::forward_kinematics	(	const Model< Scalar, nq > &	model,
		const Eigen::Matrix< Scalar, nq, 1 > &	q,
		const TargetLink &	target_link,
		const SourceLink &	source_link
	)

Computes the transform between target and the source link. The transform converts points in target frame to the source link frame.

Parameters

model	tinyrobotics model.
q	Joint configuration of the robot.
target_link	Target link, which can be an integer (index) or a string (name).
source_link	Source link, which can be an integer (index) or a string (name).

Template Parameters

Scalar	type of the tinyrobotics model.
nq	Number of configuration coordinates (degrees of freedom).
TargetLink	Type of target_link parameter, which can be int or std::string.
SourceLink	Type of source_link parameter, which can be int or std::string.

Returns

Homogeneous transform between the target and the source link.

forward_kinematics() [3/3]

template<typename Scalar , int nq>

std::vector< Eigen::Transform< Scalar, 3, Eigen::Isometry > > tinyrobotics::forward_kinematics	(	Model< Scalar, nq > &	model,
		const Eigen::Matrix< Scalar, nq, 1 > &	q
	)

Computes the transform to all the links in the tinyrobotics model.

Parameters

model	tinyrobotics model.
q	Joint configuration of the robot.

Template Parameters

Scalar	type of the tinyrobotics model.
nq	Number of configuration coordinates (degrees of freedom).

Returns

Stores the transform to all the links in model.forward_kinematics.

forward_kinematics_com() [1/2]

template<typename Scalar , int nq, typename TargetLink , typename SourceLink = int>

Eigen::Transform< Scalar, 3, Eigen::Isometry > tinyrobotics::forward_kinematics_com	(	const Model< Scalar, nq > &	model,
		const Eigen::Matrix< Scalar, nq, 1 > &	q,
		const TargetLink &	target_link,
		const SourceLink &	source_link = 0
	)

Computes the transform between source link and target center of mass. The transform converts points in the target links center of mass frame into the source link frame.

Parameters

model	tinyrobotics model.
q	Joint configuration of the robot.
target_link	Target link, which can be an integer (index) or a string (name).
source_link	Source link, which can be an integer (index) or a string (name).

Template Parameters

Scalar	type of the tinyrobotics model.
nq	Number of configuration coordinates (degrees of freedom).
TargetLink	Type of target_link parameter, which can be int or std::string.
SourceLink	Type of source_link parameter, which can be int or std::string.

Returns

Homogeneous transform from source link to target link center of mass.

forward_kinematics_com() [2/2]

template<typename Scalar , int nq>

std::vector< Eigen::Transform< Scalar, 3, Eigen::Isometry > > tinyrobotics::forward_kinematics_com	(	Model< Scalar, nq > &	model,
		const Eigen::Matrix< Scalar, nq, 1 > &	q
	)

Computes the transform between center of mass of each link and the source link.

Parameters

model	tinyrobotics model.
q	Joint configuration of the robot.

Template Parameters

Scalar	type of the tinyrobotics model.
nq	Number of configuration coordinates (degrees of freedom).

Returns

Vector of homogeneous transforms between the center of mass of each link and the source link.

get_link_idx()

template<typename Scalar , int nq, typename TargetLink >

int tinyrobotics::get_link_idx	(	const Model< Scalar, nq > &	model,
		const TargetLink &	target_link
	)

Retrieves the index of the target link in the tinyrobotics model.

Parameters

model	tinyrobotics model.
target_link	Target link, which can be an integer (index) or a string (name).

Template Parameters

Scalar	type of the tinyrobotics model.
nq	Number of configuration coordinates (degrees of freedom).
TargetLink	Type of target_link parameter, which can be int or std::string.

Returns

Index of the target link in the model.

Exceptions

std::invalid_argument

if the TargetLink type is not int or std::string.

jacobian()

template<typename Scalar , int nq, typename TargetLink >

Eigen::Matrix< Scalar, 6, nq > tinyrobotics::jacobian	(	Model< Scalar, nq > &	model,
		const Eigen::Matrix< Scalar, nq, 1 > &	q,
		const TargetLink &	target_link
	)

Computes the geometric jacobian of the target link from the base link, in the base link frame.

Parameters

model	tinyrobotics model.
q	Joint configuration of the robot.
target_link	Target link, which can be an integer (index) or a string (name).

Template Parameters

Scalar	type of the tinyrobotics model.
nq	Number of configuration coordinates (degrees of freedom).
TargetLink	Type of target_link parameter, which can be int or std::string.

Returns

The geometric jacobian of the target link from the base link, in the base link frame.