Public Types | Static Public Member Functions | List of all members
hpp::core::RelativeMotion Struct Reference

#include <hpp/core/relative-motion.hh>

Public Types

enum  RelativeMotionType {
  Constrained = 0,
  Parameterized = 1,
  Unconstrained = 2
}
 
typedef Eigen::Matrix< RelativeMotionType, Eigen::Dynamic, Eigen::Dynamic > matrix_type
 

Static Public Member Functions

static matrix_type matrix (const DevicePtr_t &robot)
 Build a new RelativeMotion matrix from a robot. More...
 
static void fromConstraint (matrix_type &matrix, const DevicePtr_t &robot, const ConstraintSetPtr_t &constraint)
 Fill the relative motion matrix with information extracted from the provided ConstraintSet. More...
 
static void recurseSetRelMotion (matrix_type &matrix, const size_type &i1, const size_type &i2, const RelativeMotionType &type)
 Set the relative motion between two joints. More...
 
static size_type idx (const JointConstPtr_t &joint)
 Get the index for a given joint. More...
 

Member Typedef Documentation

◆ matrix_type

typedef Eigen::Matrix<RelativeMotionType, Eigen::Dynamic, Eigen::Dynamic> hpp::core::RelativeMotion::matrix_type

Member Enumeration Documentation

◆ RelativeMotionType

enum hpp::core::RelativeMotion::RelativeMotionType
Enumerator
Constrained 

The relative motion is fully constrained and the constraint cannot be parameterized (has constant right-hand side)

Parameterized 

The relative motion is fully constrained but the constraint can be parameterized (has non-constant right-hand side)

Unconstrained 

The relative motion is not constrained.

Member Function Documentation

◆ fromConstraint()

static void hpp::core::RelativeMotion::fromConstraint ( matrix_type &  matrix,
const DevicePtr_t &  robot,
const ConstraintSetPtr_t &  constraint 
)
static

Fill the relative motion matrix with information extracted from the provided ConstraintSet.

Note
Only LockedJoint and RelativeTransformation of dimension 6 are currently taken into account.
Todo:
LockedJoint always has a non-constant RHS which means it will always be treated a parameterized constraint. Even when the value is not going to change...

◆ idx()

static size_type hpp::core::RelativeMotion::idx ( const JointConstPtr_t &  joint)
inlinestatic

Get the index for a given joint.

Returns
0 if joint is NULL, joint->index() otherwise.

◆ matrix()

static matrix_type hpp::core::RelativeMotion::matrix ( const DevicePtr_t &  robot)
static

Build a new RelativeMotion matrix from a robot.

Parameters
robota Device, initialize a matirx of size (N+1) x (N+1) where N is the robot number of degrees of freedom. Diagonal elements are set to RelativeMotion::Constrained, other elements are set to RelativeMotion::Unconstrained.

◆ recurseSetRelMotion()

static void hpp::core::RelativeMotion::recurseSetRelMotion ( matrix_type &  matrix,
const size_type &  i1,
const size_type &  i2,
const RelativeMotionType &  type 
)
static

Set the relative motion between two joints.

This does nothing if type is Unconstrained. The full matrix is updated as follow. For any indices i0 and i3 different from both i1 and i2:

  • set matrix(i0,i2) if i0 and i1 was constrained,
  • set matrix(i1,i3) if i2 and i3 was constrained,
  • set matrix(i0,i3) if the two previous condition are fulfilled.

The RelativeMotionType is deduced as follow: