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RigidBodyAddedMass Class Reference
Inheritance diagram for RigidBodyAddedMass:
Collaboration diagram for RigidBodyAddedMass:

Public Member Functions

function RigidBodyAddedMass (frame_id, manip, MaOrigin)
 creates a force element that adds added-mass at new frame location More...
 
function augmentParentInertia (obj, manip)
 Augments the inertia of the parent link to include added mass. More...
 
function computeSpatialForce (obj, manip, q, qd)
 Adds the gravity correction from added mass This force is ONLY necessary because the Featherstone solver imposes gravitational acceleration at the base of the manipulator rather than imposing a gravity for at each node Imposing at the base assumes that F_gravity = (M+Ma)*g, rather than F_gravity = M*g Essentially, gravitional and inertial mass are NOT the same if added mass forces are assumed (isn't physics fun?) More...
 
- Public Member Functions inherited from RigidBodyForceElement
function updateBodyCoordinates (obj, body_ind, T_old_body_to_new_body)
 
function setInputNum (obj, input_num)
 
function energy (obj, manip, q, qd)
 
- Public Member Functions inherited from RigidBodyElement
function bindParams (body, model, pval)
 Bind parameters from msspolys to doubles. More...
 

Static Public Member Functions

static function parseURDFNode (model, name, robotnum, node, options)
 
static function moveSpatialMassMatrix (c, I_old)
 Moves an added mass matrix (or spatial mass matrix) by c. More...
 
- Static Public Member Functions inherited from RigidBodyForceElement
static function cartesianForceToSpatialForce (varargin)
 This method is deprecated. More...
 

Public Attributes

Property kinframe
 
Property MaOrigin
 added mass of body, as seen at xyz origin More...
 
Property MaBody
 added mass, as seen by the parent body coordinates More...
 
- Public Attributes inherited from RigidBodyForceElement
Property name
 
Property direct_feedthrough_flag
 
Property input_num
 
Property input_limits
 
- Public Attributes inherited from RigidBodyElement
Property param_bindings
 structure containing msspoly parameterized representations of some properties More...
 

Constructor & Destructor Documentation

function RigidBodyAddedMass ( frame_id  ,
manip  ,
MaOrigin   
)

creates a force element that adds added-mass at new frame location

Parameters
frame_id= RigidBodyFrame index specifying the location added mass coefficients have been located
manip= RigidBodyManipulator that the frame_id references
MaOrigin= added mass matrix as seen by origin of added mass frame (in Featherstone's spatial form for consistency, not 123456 as is literature norm)
Return values
obj

Member Function Documentation

function augmentParentInertia ( obj  ,
manip   
)

Augments the inertia of the parent link to include added mass.

Return values
manip
function computeSpatialForce ( obj  ,
manip  ,
,
qd   
)

Adds the gravity correction from added mass This force is ONLY necessary because the Featherstone solver imposes gravitational acceleration at the base of the manipulator rather than imposing a gravity for at each node Imposing at the base assumes that F_gravity = (M+Ma)*g, rather than F_gravity = M*g Essentially, gravitional and inertial mass are NOT the same if added mass forces are assumed (isn't physics fun?)

Return values
force
static function moveSpatialMassMatrix ( ,
I_old   
)
static

Moves an added mass matrix (or spatial mass matrix) by c.

Equivalent to mcI(m,c,Icm) but works for non-scalar m and allows for inertias to not be about center of mass

Parameters
I_oldis spatial mass matrix in [angular;velo] form as consistent with Featherstone's notation
c[3x1] is the vector from the NEW origin to the OLD origin algebra tested with test/moveSpatialMassMatrixTest
Return values
I_new
static function parseURDFNode ( model  ,
name  ,
robotnum  ,
node  ,
options   
)
static
Return values
model
obj

Member Data Documentation

Property kinframe
Property MaBody

added mass, as seen by the parent body coordinates

Property MaOrigin

added mass of body, as seen at xyz origin


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