Joint

Class Joint()

Joint(parent='MODEL', name='Body_n', label='Body_n', active=True, 
type='BallJoint', b1=None, b2=None, origin=None, align_meth1='Point', align_pt1=None, 
align_vec1=None, align_meth2='Point', align_pt2=None, align_vec2=None, 
align_type='Inplane', inplane_type='Inplane', inline_type='Origin', ujoint_meth1='SHAFT', 
ujoint_meth2='SHAFT', ic_use_trans=False, ic_trans_disp=0, ic_trans_vel=0, 
ic_use_rot=False, ic_rot_disp=0, ic_rot_vel=0, pitch=0, allow_compliance=False, isbush=False)

A Joint.

Joints create lower pair constraints. A lower pair is an idealized form of constraint where the constraint can be represented using two reference frames, or coordinate systems, belonging to two different bodies. The origin, axis, or plane of one reference frame is said to be constrained with respect to the origin, axis, or plane of another reference frame.

Method:

getAssociatedGraphics

Keyword Arguments

Instances

Notes

1. The parent parameter can only be initialized by the constructor and should not be modified directly.

2. Only parent can be used as a positional argument in the constructor.

3. Instance is a reference to an entity. You cannot modify an instance, but can modify its properties.

Methods

getAssociatedGraphics()

Get all the graphics that are associated with this object.

Returns:

List of all graphic associated with this joint.

Return type:

(list)

Class JointPair()

JointPair(parent='MODEL', name='JointPair_n', label='JointPair_n', active=True, sym='NONE')

Joint pair containing left and right instances of singles.

Keyword Arguments

Instances

Notes

Instance is a reference to an entity. You cannot modify an instance, but can modify its properties.

Class Friction()

Friction(**kwds)

Utility class to hold and modify friction properties for a joint.

Keyword Arguments

Notes

You cannot create instances of the Friction class. This class is used to modify the friction properties of a joint.

========
Create and modify attributes of a Joint.
>>> from hw import mview
>>> #Create a Ball joint and references
>>> j1 = mview.Joint(name = 'j1', type = 'BallJoint')
>>> body1 = mview.Body(label = 'refbody')
>>> #Set values for attributes
>>> j1.b1 = body1
>>> j1.b2 = 'B_Ground'
>>> j1.origin = mview.getModel().P_Global_Origin
>>> #Get values of attributes
>>> j1.friction.use_friction
False
>>> #Set multiple values at once
>>> j1.friction.setValues(use_friction = True,mu_static = 0.5)
>>> #Get list of properties/atrributes for all types of joints
>>> j1.getPropertyNames()
['name', 'label', 'note', 'num', 'id', 'active', 'ifstate', 'varname', 'sym', 'type', 'b1', 'b2',
'origin', 'align_meth1', 'align_pt1', 'align_vec1', 'align_meth2', 'align_pt2', 'align_vec2',
'align_type', 'inplane_type', 'inline_type', 'ujoint_meth1', 'ujoint_meth2', 'ic_use_trans',
'ic_trans_disp', 'ic_trans_vel', 'ic_use_rot', 'ic_rot_disp', 'ic_rot_vel', 'pitch',
'allow_compliance', 'isbush', 'bush', 'friction', 'i', 'j', 'joint_i', 'joint_j']
>>> #Create a compliant joint
>>> j2 = mview.Joint(type = 'RevJoint',allow_compliance = True)
>>> j2.b1 = body1
>>> j2.setValues(b1 = body1,b2 = 'B_Ground',origin = 'P_Global_Origin')
>>> j2.align_meth1 = 'VECTOR'
>>> j2.align_vec1 = 'V_Global_Z'
>>> #Set bushing properties
>>> j2.isbush = True
>>> #Linear value of stiffness
>>> j2.bush.kx.lin = 100
>>> j2.bush.cty.type = 'CRV'
>>> #Nonlinear curve value for damping
>>> c1 = mview.Curve(x_type = 'VALUE',y_type = 'VALUE',x_value = [0,1],y_value = [10,20])
>>> j2.bush.cty.crv = c1
>>> #Set interpolation type and independent variable
>>> j2.bush.cty.int_type = 'CUBIC'
>>> j2.bush.cty.indep_var = '`TIME`'
>>> #These steps can be repeated for any type of joint, with associated properties