bush Module

All bush elements are defined in this file. This includes:

• CBUSH
• CBUSH1D
• CBUSH2D

All bush elements are BushElement and Element objects.

class pyNastran.bdf.cards.elements.bush.BushElement

Bases: pyNastran.bdf.cards.base_card.Element

Cid(self)

Mass(self)

get_edge_ids(self)

Return the edge IDs

class pyNastran.bdf.cards.elements.bush.CBUSH(eid, pid, nids, x, g0, cid=None, s=0.5, ocid=-1, si=None, comment='')

Bases: pyNastran.bdf.cards.elements.bush.BushElement

Generalized Spring-and-Damper Connection

Defines a generalized spring-and-damper structural element that may be nonlinear or frequency dependent.

1	2	3	4	5	6	7	8	9
CBUSH	EID	PID	GA	GB	GO/X1	X2	X3	CID
	S	OCID	S1	S2	S3

Creates a CBUSH card

Parameters:

eid : int

Element id

pid : int

Property id (PBUSH)

nids : List[int, int]

node ids; connected grid points at ends A and B The nodes may be coincident, but then cid is required.

x : List[float, float, float]; None

List : the directional vector used to define the stiffnesses

or damping from the PBUSH card

None : use g0

g0 : int/None

int : the directional vector used to define the stiffnesses

or damping from the PBUSH card

None : use x

cid : int; default=None

Element coordinate system identification. A 0 means the basic coordinate system. If CID is blank, then the element coordinate system is determined from GO or Xi.

s: float; default=0.5

Location of spring damper (0 <= s <= 1.0)

ocid : int; default=-1

Coordinate system identification of spring-damper offset. (Integer > -1; Default = -1, which means the offset point lies on the line between GA and GB)

si : List[float, float, float]; default=None

Components of spring-damper offset in the OCID coordinate system if OCID > 0. None : [None, None, None]

comment : str; default=’‘

a comment for the card

Cid(self)

G0(self)

Ga(self)

Gb(self)

OCid(self)

_get_x_g0(self)

_properties = ['_field_map']

classmethod add_card(card, comment='')

Adds a CBUSH card from BDF.add_card(...)

Parameters:

card : BDFCard()

a BDFCard object

comment : str; default=’‘

a comment for the card

cross_reference(self, model)

Cross links the card so referenced cards can be extracted directly

Parameters:

model : BDF()

the BDF object

classmethod export_to_hdf5(h5_file, model, eids)

exports the elements in a vectorized way

node_ids

raw_fields(self)

repr_fields(self)

Gets the fields in their simplified form

Returns:

fields : List[varies]

the fields that define the card

safe_cross_reference(self, model, xref_errors)

Cross links the card so referenced cards can be extracted directly

Parameters:

model : BDF()

the BDF object

type = 'CBUSH'

uncross_reference(self)

Removes cross-reference links

update_by_cp_name(self, cp_name, value)

write_card(self, size=8, is_double=False)

Writes the card with the specified width and precision

Parameters:

size : int (default=8)

size of the field; {8, 16}

is_double : bool (default=False)

is this card double precision

Returns:

msg : str

the string representation of the card

class pyNastran.bdf.cards.elements.bush.CBUSH1D(eid, pid, nids, cid=None, comment='')

Bases: pyNastran.bdf.cards.elements.bush.BushElement

Ga(self)

Gb(self)

classmethod add_card(card, comment='')

Adds a CBUSH1D card from BDF.add_card(...)

Parameters:

card : BDFCard()

a BDFCard object

comment : str; default=’‘

a comment for the card

cross_reference(self, model)

Cross links the card so referenced cards can be extracted directly

Parameters:

model : BDF()

the BDF object

classmethod export_to_hdf5(h5_file, model, eids)

exports the elements in a vectorized way

node_ids

nodes

nodes_ref

raw_fields(self)

safe_cross_reference(self, model, xref_errors)

Cross links the card so referenced cards can be extracted directly

Parameters:

model : BDF()

the BDF object

type = 'CBUSH1D'

uncross_reference(self)

Removes cross-reference links

write_card(self, size=8, is_double=False)

Writes the card with the specified width and precision

Parameters:

size : int (default=8)

size of the field; {8, 16}

is_double : bool (default=False)

is this card double precision

Returns:

msg : str

the string representation of the card

class pyNastran.bdf.cards.elements.bush.CBUSH2D(eid, pid, nids, cid=0, plane='XY', sptid=None, comment='')

Bases: pyNastran.bdf.cards.elements.bush.BushElement

2-D Linear-Nonlinear Connection Defines the connectivity of a two-dimensional Linear-Nonlinear element.

Ga(self)

Gb(self)

classmethod add_card(card, comment='')

Adds a CBUSH2D card from BDF.add_card(...)

Parameters:

card : BDFCard()

a BDFCard object

comment : str; default=’‘

a comment for the card

cross_reference(self, model)

Cross links the card so referenced cards can be extracted directly

Parameters:

model : BDF()

the BDF object

classmethod export_to_hdf5(h5_file, model, eids, encoding='ascii')

exports the elements in a vectorized way

node_ids

nodes

raw_fields(self)

safe_cross_reference(self, model, xref_errors)

Cross links the card so referenced cards can be extracted directly

Parameters:

model : BDF()

the BDF object

type = 'CBUSH2D'

uncross_reference(self)

Removes cross-reference links

write_card(self, size=8, is_double=False)

Writes the card with the specified width and precision

Parameters:

size : int (default=8)

size of the field; {8, 16}

is_double : bool (default=False)

is this card double precision

Returns:

msg : str

the string representation of the card