Adams Car Package > Adams Car Ride > Working with Components > General Bushing

General Bushing

Component Name

ac_general_bushing

Source Directory

/$MDI_RIDE_PLUGIN/template_builder/udes/ac_general_bushing

Description

This component is based on a GFORCE element such as the standard ac_bushing. The forces in all six directions are orthogonal and can be coupled in rectangular, cylindrical or spherical ways. The total force from this element is sum of static spline force, TFSISO force, Bouc-Wen hysteresis force, preload and viscous damping force.

Specifications

.ARIDE.parts.ac_general_bushing

Parameters

Parameter:	Type:	Function:
property_file	string variable	name of property file
t_preload_x	real variable	translational preload
t_preload_y	real variable	translational preload
t_preload_z	real variable	translational preload
r_preload_x	real variable	rotational preload
r_preload_y	real variable	rotational preload
r_preload_z	real variable	rotational preload
t_offset_x	real variable	translational offset
t_offset_y	real variable	translational offset
t_offset_z	real variable	translational offset
r_offset_x	real variable	rotational offset
r_offset_y	real variable	rotational offset
r_offset_z	real variable	rotational offset
i_geoMarker	marker	geometry ref marker
j_geoMarker	marker	geometry ref marker
geoRadius	real variable	geometry radius
geoLength	real variable	geometry length

Input Parameters

Input parameter:	Type:	Function:
i_marker	object variable	action marker
j_marker	object variable	marker whose parent is the reaction part and reference marker

Output Parameters

none

Objects

Object:	Type:	Function:
bushing_shape	integer value	0 or 1: rectangular coupling 2: cylindrical coupling 3: spherical coupling
gen_coupling	integer value	0: Uncouple Bouc-Wen force from linear stiffness force 1: Couple Bouc-Wen force with linear stiffness force 2: Revised Bouc-Wen force with linear stiffness force 3: Revised Bouc-Wen force with linear stiffness force, improved on rotational direction
(tx-rz)_data_array	Adams array	Array to pass stiffness and damping types, scales, spline ID, preload, damping and velocity offsets and scales, static spline ID, Bouc-Wen parameters ALPHA, ZETA, OMEGA, K, hysteresis type, hysteresis spline ID/Bouc-Wen DIFF ID, hysteresis/Bouc-Wen force scale, TFSISO output array ID and TFSISO force scale to the subroutine
data_array_(x-az)	Adams array	array to pass the Bouc-Wen model parameters BETA, GAMMA, A and N to the subroutine
(x-az)_alpha	real variable	Bouc-Wen parameter
(x-az)_beta	real variable	Bouc-Wen parameter
(x-az)_gamma	real variable	Bouc-Wen parameter
(x-az)_zeta	real variable	Bouc-Wen parameter
(x-az)_omega	real variable	Bouc-Wen parameter
(x-az)_a	real variable	Bouc-Wen parameter
(x-az)_n	real variable	Bouc-Wen parameter
(x-az)_num	real variable	TFSISO Numerator array
(x-az)_den	real variable	TFSISO Denominator array
fx_spline	Adams spline	Static force spline in x direction
fy_spline	Adams spline	Static force spline in y direction
fz_spline	Adams spline	Static force spline in z direction
tx_spline	Adams spline	Static torque spline in ax direction
ty_spline	Adams spline	Static torque spline in ay direction
tz_spline	Adams spline	Static torque spline in az direction
i_graphic	revolution	graphics on I part
j_graphic	cylinder	graphics on J part
disp_request	request	displacement request
velo_request	request	velocity request
force_request	request	force request
gforce	gforce	bushing dependent bushing gforce subroutine as part of the aride_solver::FD_BUSHING

Request Definition

disp_request

user (905,1,i_marker,j_marker,gforce) and routine = aride_solver::reqaride

Component name:	Component units:	Definition:
dx	length	x-distance between i_marker and j_marker
dy	length	y-distance between i_marker and j_marker
dz	length	z-distance between i_marker and j_marker
dm	length	magnitude
ax	angle	angle about x
ay	angle	angle about y
az	angle	angle about z
amag	angle	magnitude

velo_request

user (905,2,i_marker,j_marker,gforce) and routine = aride_solver::reqaride

Component name:	Component units:	Definition:
vx	velocity	x-velocity between i_marker and j_marker
vy	velocity	y-velocity between i_marker and j_marker
vz	velocity	z-velocity between i_marker and j_marker
vm	velocity	magnitude
wx	angular_velocity	x-angular velocity between i_marker and j_marker
wy	angular_velocity	y- angular velocity between i_marker and j_marker
wz	angular_velocity	z- angular velocity between i_marker and j_marker
wm	angular_velocity	magnitude

force_request

user (905,3,i_marker,j_marker,gforce) and routine = aride_solver::reqaride

Component name:	Component units:	Definition:
bushing_fx	force	x-force between i_marker and j_marker
bushing_fy	force	y-force between i_marker and j_marker
bushing_fz	force	z-force between i_marker and j_marker
fm	force	Force magnitude (translational)
bushing_tx	torque	x-torque between i_marker and j_marker
bushing_ty	torque	y- torque between i_marker and j_marker
bushing_tz	torque	z- torque between i_marker and j_marker
tm	torque	Torque magnitude (rotational)

Subsystem Parameters

Top level:	Sub level:
property_file
t_preload_(x-z)
r_preload_(x-z)
t_offset_(x-z)
r_offset_(x-z)

Design Parameters

Parameter:	Type:	Function:
fx_scaling_factor	real variable	scaling factor (DOE)
fy_scaling_factor	real variable	scaling factor (DOE)
fz_scaling_factor	real variable	scaling factor (DOE)
tx_scaling_factor	real variable	scaling factor (DOE)
ty_scaling_factor	real variable	scaling factor (DOE)
tz_scaling_factor	real variable	scaling factor (DOE)

Macros

Create Macro: (call: acar template_builder instance ac_general_bushing create) Adams Car Ride executes this macro when you create an instance of the definition ac_general_bushing.

Modify Macro: (call: acar template_builder instance ac_general_bushing modify) Adams Car Ride executes this macro when you modify an instance of the definition ac_general_bushing.

Delete Macro: (call: acar template_builder instance ac_general_bushing delete) This macro deletes all the entities which have been created exclusively for the instance.

About Bushing Property File

To avoid confusion with the .gbu files, any general bushing can be used in Adams Car Assembly to calculate the bushing force and behavior but can also be used in IPIT for parameter identification of the bushing parameters out of measurement data. The headings marked below with (**) are used in IPIT during the identification only, these are not required by Adams Solver for running a simulation.

The IPIT identifies the bushing parameters in each direction for which test data has been provided in the property file.The following shows a number of important parameters that must be defined in the GBU property file. Please refer to Isolator-Parameter Identification Tool (IPIT) help for further details of each parameter, its meaning and about its default values.

The block [MDI_HEADER] must be exactly the same in all the .gbu files.

In the block [UNITS] the test data units should be specified. For IPIT the units are fixed to respectively N, mm, kg, degrees and second.

The block [GENERAL] must contain all parameters as listed in the sample file.

■The DEFINITION is always '.aride.attachment.ac_general_bushing'

■The BUSHING_COORDINATE(**, in old formatted files only) can be x, y, z, ax, ay or az. This parameter it is only used by IPIT and it determines the co-ordinate in which the bushing parameters will be identified.

■BUSHING_SHAPE can be 0 or 1 for rectangular coupling, 2 for cylindrical coupling or 3 for spherical coupling. All these types are supported in Adams Car Models. IPIT uses rectangular coupling during identification only. Further the bushing coordinate of the identifying direction is required.

■BUSHING_COUPLING can be set to 0 for un-coupled Bouc-Wen force, 1 for coupled Bouc-Wen force or 2 for revised Bouc-Wen force or 3 for corrected Bouc-Wen force with correction for rotational directions.

The blocks [DAMPING], [PRELOAD] and [OFFSET] are optional.

The blocks [SPLINE_SCALES], [HYST_SCALES] and [TFSISO_SCALES] are compulsory.

The blocks [FX_CURVE], [FY_CURVE], [FZ_CURVE], [TX_CURVE], [TY_CURVE], [TZ_CURVE] are given to supply static splines.

The [BUSHING_PARAMETERS] block supplies the bushing parameters values. Both in an Adams Car Assembly and IPIT, your bushing force is calculated using these parameters. The IPIT updates these parameters during the identification process.

In old formatted files the blocks [BUSHING_TEST_DATA](**) and [BUSHING_IDENTIFICATION_DATA](**) may still exist. This data is valid for just one the direction specified in BUSHING_COORDINATE(**).

The latest formatted files can contain the data for all 6 direction by the use of [BUSHING_TEST_DATA_X/Y/Z/AX/AY/AZ] (**) and [BUSHING_IDENTIFICATION_DATA_X/Y/Z/AX/AY/AZ] (**) respectively.

By loading an old formatted General Bushing property file (.gbu) into the IPIT and saving it again, will convert the old format to the latest format.

See Example General Bushing Property File.