Directions Block
The Directions block selects what force formulations the simulation model uses for
each force and torque direction. This is a mandatory block. The block contains a
table where each row is a force method and each column a force or torque direction.
To select or turn on a force formulation for a given force direction, enter
1
in the corresponding row and column. To turn off a force
method for a given force direction, enter 0
(zero).
Parameter | Type | Units | Description |
---|---|---|---|
ACTIVITY | Sub-block | - | This sub-block is specified as
(ACTIVITY) |
FORMULATION | String | - | Valid choices are:
|
FX | Integer | - | Valid choices are:
|
FY | Integer | - | |
FZ | Integer | - | |
TX | Integer | - | |
TY | Integer | - | |
TZ | Integer | - |
Some of the formulations are mutually exclusive and some of the formulations can be added in parallel.
- Each force direction (one column in the matrix below) can contain only one stiffness model and one damping model.
HYDROMOUNT_DAMPING
can be used for one translational direction ONLY. Because the software does not impose this limitation, understanding the impracticality of fitting more than one hydromount per attachment is important.- Where
HYDROMOUNT_DAMPING
is used (for FX, FY, FZ), theRUBBER_DAMPING
for the same direction CANNOT be used. CONSTANT_STIFFNESS
,SPLINE_STIFFNESS
andCUBIC_STIFFNESS
are mutually exclusive.
In the following example, the stiffness models are shown in blue and damping models in green.
- For FX:
SPLINE_STIFFNESS
andRUBBER_DAMPING
are active. - For FY:
CONSTANT_STIFFNESS
andHYDROMOUNT_DAMPING
are active. - For FZ:
CONSTANT_STIFFNESS
andCONSTANT_DAMPING
are active. - For TX:
CUBIC_STIFFNESS
andCONSTANT_DAMPING
are active. - For TY:
CONSTANT_STIFFNESS
andCONSTANT_DAMPING
are active. - For TZ:
SPLINE_STIFFNESS
andRUBBER_DAMPING
are active.
$$---------------------------------------------------------- DIRECTIONS
[DIRECTIONS]
(ACTIVITY)
{ formulation FX FY FZ TX TY TZ }
'SPLINE_STIFFNESS' 1 0 0 0 0 1
'CONSTANT_STIFFNESS' 0 1 1 0 1 0
'CUBIC_STIFFNESS' 0 0 0 1 0 0
'CONSTANT_DAMPING' 0 0 1 1 1 0
'RUBBER_DAMPING' 1 0 0 0 0 1
'HYDROMOUNT_DAMPING' 0 1 0 0 0 0
The net force output for any direction is the sum of the forces due to the active force formulations in that direction.