Command Element

Description

Modifies a rigid body element.

Format

<Body_Rigid>

    id                  = "integer"

  [ inertia_xx          = "real"

    inertia_yy          = "real"

    inertia_zz          = "real"

    inertia_xy          = "real"

    inertia_yz          = "real"

    inertia_xz          = "real"

    v_ic_x              = "real"

    v_ic_y              = "real"

    v_ic_z              = "real"

    w_ic_x              = "real"

    w_ic_y              = "real"

    w_ic_z              = "real"

    is_wet_body         = "boolean"

    cp_inp_id           = "integer”

  ]

/>

Attributes

id

Element identification number, (integer>0).  This is a number that is unique among all Body_Rigid elements.

inertia_xx
inertia_yy
inertia_zz
inertia_xy
inertia_yz
inertia_xz

Defines the moments of inertia and the products of inertia of the rigid body about the origin of im_id and about its x-, y- and z-axes, respectively.

The attributes inertia_xx, inertia_yy, inertia_zz, inertia_xy, inertia_yz and inertia_xz are optional.

If a rigid body is fully constrained and you are not interested in the constraint forces, then these need not be specified.

When specified, inertia_xx, inertia_yy, and inertia_zz need to be strictly positive.

v_ic_x

v_ic_y

v_ic_z

Specifies the initial translational velocities of the Body_Rigid CG Marker along the global x, y and z axes.  All three attributes are optional.

w_ic_x

w_ic_y

w_ic_z

Specifies the initial rotational velocities of the Body_Rigid CG Marker along the global x, y and z axes.  All three attributes are optional.

is_wet_body

Modifies whether the rigid body will interact with the AcuSolve model in co-simulation.

“TRUE” means that forces and torques computed in the AcuSolve simulation will be applied to the center of gravity of this body.

“FALSE” means that forces and torques computed in the AcuSolve simulation will not be applied to this body.

cp_inp_id

Modifies the ID of the Control_PlantInput element that holds the forces and torques computed in the AcuSolve simulation that will be applied to this rigid body.

Example

<Body_Rigid

    Id         = "101"

    inertia_xx = "10000."

    inertia_yy = "10000."

    inertia_zz = "10000."

/>

Command Element

Description

Modifies a PART element.

Declaration

def PART(id, LABEL="", GROUND=False, MASS=0.0, CM=0, IM=0, IP=[], VX=0.0, VY=0.0, VZ=0.0, WX=0.0, WY=0.0, WZ=0.0 ):

Attributes

id

Element identification number (integer>0). This number is unique among all the PART elements.

LABEL

Modifies the name of the PART element.

GROUND

Modifies the PART being defined as the Ground PART or not. The value True indicates that the PART that is being defined is the Ground PART. The value "False" indicates that the PART is not the Ground PART. This attribute is an optional attribute. When not specified, it defaults to "False".

MASS

Modifies the mass of the PART object. When specified, MASS must be a positive number. The attribute MASS is optional. If a PART is fully constrained and you are not interested in the constraint forces, then MASS need not be specified. When omitted, zero mass is assumed.

CM

Modifies the ID of the Marker that is located at the center-of-mass of the PART.

IM

Modifies the ID of the Marker whose x, y and z coordinate system would be used to define the inertia matrix. This attribute is optional. When not specified, it defaults to CM.

IP

Modifies the mass moments of inertia and the products of inertia of the PART about the x,y,z axes of IM, in the order of Ixx,Iyy,Izz,Ixy,Ixz,Iyz. These attributes are to be specified in the following order: inertia_xx, inertia_yy, inertia_zz, inertia_xy, inertia_yz, and inertia_zx. These attributes are optional. If a PART is fully constrained and you are not interested in the constraint forces, then these attributes need not be specified. However, when specified:

Inertia_xx > 0

Inertia_yy > 0

Inertia_zz > 0

VX

Modifies the initial translational velocity of the PART along the VM x-axis.

VY

Modifies the initial translational velocity of the PART along the VM y-axis.

VZ

Modifies the initial translational velocity of the PART along the VM z-axis.

WX

Modifies the initial rotational velocity of the PART about the WM x-axis.

WY

Modifies the initial rotational velocity of the PART about the WM y-axis.

WZ

Modifies the initial rotational velocity of the PART about the WM z-axis.

Comments

See Body_Rigid

Example

The example below demonstrates the modifications to a PART.

PART(101, IP=[10000,10000,10000,0,0,0])