Adams Car Package > Adams Car Ride > Working with Components > Hydromount

Hydromount

Component Name

ac_hydro_bushing

Source Directory

/$MDI_RIDE_PLUGIN/template_builder/udes/hydro_bushing

Description

This component is based on the Weber model, which consists of a hydro path, a parallel spring, and a parallel damper.

Hydromount Model

The nonlinear model consists of up to nine parameters:

■CouplingStiffness

■RubberStiffness

■LinearFluidDamping

■RubberDamping

■EffectiveFluidMass

■CouplingStiffnessDeclining

■QuadraticFluidDamping

■Clearance

■Regressive Stiffness

For further details, please refer Hydromount Model.

Specifications

.ARIDE.parts.ac_hydro_bushing

Parameters

Parameter:	Type:	Function:
property_file	string variable	name of property file
bushing_property_file	string variable	name of the bushing property file
super_impose_bushing	integer variable	togggle if the spline from the original bushing property file will be superimposed in the direction of the hydro component
hydro_coordinate	string variable	hydro direction coordinate
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 Parameter

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:
data_array	Adams array	array to pass the scaling factors and preloads to the field subroutine
fx_spline	Adams spline	force spline set to 0, depent on Hydro_Direction
fy_spline	Adams spline	set to 0, depend on Hydro_Direction
fz_spline	Adams spline	set to 0, depend on Hydro_Direction
tx_spline	Adams spline	torque spline
ty_spline	Adams spline
tz_spline	Adams spline
hydro_test_data_cdyn	Adams spline	stiffness
hydro_test_data_phase	Adams spline	angle
hydro_identification_data_cdyn	Adams spline	stiffness
hydro_identification_data_phase	Adams spline	angel
i_graphic	revolution	graphics on I part
j_graphic	cylinder	graphic on J part
disp_request	request	displacement request
velo_request	request	velocity request
force_request	request	force request
output_request	request	hydroForce, Fluidvelocity, Fluiddisplacement
field	field	standard bushing field subroutine (900)
hydro_force_i	sforce	force representing the hydro path in z direction (action only)
hydro_force_j	sforce	hydro_force_i
hydro_disp	state variable	displacement difference between force marker and channel fluid displacement including clearance
hyrdo_diff_channel_disp	diff	displacement state of fluid in channel
hydro_Direction	string	acting direction of hyrdo force: values : 'x' \| 'y' \| 'z'
hydro_DirectionMarker	marker	direction for hydro_force_i and _j
hydro_RubberStiffnes	real_variable	units: translational stiffness [N/mm]
hydro_RubberDamping	real_variable	units: translational damping [Ns/mm]
hydro_CouplingStiffness	real_variable	units: translational stiffness [N/mm]
hydro_LinearFluidDamping	real_variable	units: translational damping [Ns/mm]
hydro_QuadraticFluidDamping	real_variable	units: translational damping [Ns²/mm²]
hydro_CouplingStiffnessDeclining	real_variable	units: [1/mm²]
hydro_EffectiveFluidMass	real_variable	units: [kg]
hyrdo_Clearance	real_variable	units: [mm]

Request Definition

disp_request

user (905,1,i_marker,j_marker,field)

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,field)

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
wy	angular_velocity
wz	angular_velocity
wm	angular_velocity	magnitude

force_request

user (905,3,i_marker,j_marker,field)

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	magnitude
bushing_tx	torque
bushing_ty	torque
bushing_tz	torque
tm	torque	magnitude

output_request

Component:	Component name:	Component units:	Definition:
f2	hydroForce	force	force on i-marker of sforce hydro_force_i
f3	Fluidvelocity	velocity	state of hydro_diff_channel_velo
f4	Fluiddisplacement	displacement	state of hydro_diff_channel_disp

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)
Hydro_RubberStiffnes_scaling_factor	real_variable	scaling factor (DOE)
Hydro_RubberDamping_scaling_factor	real_variable	scaling factor (DOE)
Hydro_CouplingStiffness_scaling_factor	real_variable	scaling factor (DOE)
Hydro_LinearFluidDamping_scaling_factor	real_variable	scaling factor (DOE)
Hydro_QuadraticFluidDamping_scaling_factor	real_variable	scaling factor (DOE)
Hydro_CouplingStiffnessDeclining_scaling_factor	real_variable	scaling factor (DOE)
Hydro_EffectiveFluidMass_scaling_factor	real_variable	scaling factor (DOE)
Hydro_Clearance_scaling_factor	real_variable	scaling factor (DOE)

Macros

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

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

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

About Input Hydromount Property Files

The block [MDI_HEADER] must be exactly the same as in the example input hydromount property file.

In the block [UNITS] you could modify LENGTH to be either m or mm.

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

■The DEFINITION is always '.ride.attachment.ac_hydro_bushing'.

■The HYDRO_COORDINATE can be x, y or z. This parameter determines the acting direction of the hydro force with respect to the ac_hydro_bushing reference system.

■The BUSHING_PROPERTY_FILE is a standard ac_bushing property file that defines all six stiffness and damping components of a bushing.

■The SUPER_IMPOSE_BUSHING parameter can be set to:

♦Off - The bushing component with the same direction as the hydro force component is set to zero.

♦On - The bushing component is superimposed. The superimpose option is useful because it lets you add an impact stiffness to the hydro force component. During the identification process, the bushing stiffness and damping coefficients are not considered.

■The block [HYDRO_TEST_DATA] contains four columns of data. These are the measured data of the hydromount. For every amplitude you must have the same frequencies. The number of amplitudes is not fixed. You could also use a property file including the hydro parameters, which you can edit manually, or use a file that was written by a previous identification process. This allows you to first use rather larger error tolerances to speed up the process with relatively rough results before you run the identification process using those results as initial values with a smaller error tolerance. Or you could add additional test data later and redo the identification based on previously identified parameters.

Example Input Hydromount Property File

The following is a sample input hydromount property file (extension .hbu). This sample file contains the minimum set of required data.

Learn about input hydromount property files.

$-----------------------------------------------------------MDI_HEADER

[MDI_HEADER]

FILE_TYPE = 'hbu'

FILE_VERSION = 1.0

FILE_FORMAT = 'ASCII'

$----------------------------------------------------------------UNITS

[UNITS]

LENGTH = 'mm'

FORCE = 'newton'

ANGLE = 'degrees'

MASS = 'kg'

TIME = 'second'

$--------------------------------------------------------------GENERAL

[GENERAL]

DEFINITION = '.ride.attachment.ac_hydro_bushing'

HYDRO_COORDINATE = 'z'

BUSHING_PROPERTY_FILE = '<ride>/bushings.tbl/mdi_0001.bus'

SUPER_IMPOSE_BUSHING = 'off'

$------------------------------------------------------HYDRO_TEST_DATA [HYDRO_TEST_DATA]

{amplitude	frequency	cdyn	phase}
0.100000	5.000000	620.0	7.7
0.100000	8.000000	652.0	16.2
0.100000	10.000000	776.0	20.4
0.100000	12.000000	911.0	20.2
0.100000	15.000000	1038.0	12.9
0.100000	20.000000	963.0	5.5
0.100000	25.000000	902.0	4.0
0.100000	30.000000	881.0	4.3
0.100000	40.000000	841.0	5.3
0.100000	50.000000v	838.0	6.6
0.800000	5.000000	620.0	9.9
0.800000	8.000000	620.0	20.9
0.800000	10.000000	691.0	29.1
0.800000	12.000000	855.0	32.4
0.800000	15.000000	1085.0	25.2
0.800000	20.000000	1142.0	12.0
0.800000	25.000000	1100.0	7.0
0.800000	30.000000	1068.0	5.4
0.800000	40.000000	1020.0	5.3
0.800000	50.000000	1031.0	5.6

Example Output Hydromount Property File

The following is an example output hydromount property file. We left out the data for frequencies 4 - 39 Hz.

$-----------------------------------------------------MDI_HEADER

[MDI_HEADER] FILE_TYPE = 'hbu'

FILE_VERSION = 1.0

FILE_FORMAT = 'ASCII'

$-----------------------------------------------------UNITS

[UNITS]

LENGTH = 'mm'

FORCE = 'newton'

ANGLE = 'degrees'

MASS = 'kg'

TIME = 'second'

$-----------------------------------------------------GENERAL

[GENERAL]

DEFINITION = '.ride.attachment.ac_hydro_bushing'

HYDRO_COORDINATE = 'z'

BUSHING_PROPERTY_FILE = '<ride>/bushings.tbl/mdi_0001.bus'

SUPER_IMPOSE_BUSHING = 'off'

$-----------------------------------------------------HYDRO_PARAMETERS [HYDRO_PARAMETERS]

RUBBER_STIFFNESS = 406.544598

RUBBER_DAMPING = 0.29298822

COUPLING_STIFFNESS = 282.526692

COUPLING_STIFFNESS_DECLINING = 0.071232

LINEAR_FLUID_DAMPING = 1.10642663

QUADRATIC_FLUID_DAMPING = 0.01834762

EFFECTIVE_FLUID_MASS = 51.416425

CLEARANCE = 0.0

$-----------------------------------------------------HYDRO_IDENTIFICATION_DATA

[HYDRO_IDENTIFICATION_DATA]

{amplitude	frequency	cdyn	phase}
0.100000	1.000000	404.863819	1.243071
0.100000	2.000000	399.691551	2.618614
0.100000	3.000000	388.455029	4.605679
... continue
0.100000	40.000000	713.285910	6.099968
0.500000	1.000000	404.772004	1.302907
0.500000	2.000000	399.309176	2.830528
0.500000	3.000000	389.903747	4.774778
... continue
0.500000	40.000000	716.810500	6.126563
1.000000	1.000000	404.777324	1.347649
1.000000	2.000000	399.296585	3.024592
1.000000	3.000000	390.207932	5.272207
... continue
1.000000	40.000000	700.288389	6.281555

$-----------------------------------------------------HYDRO_TEST_DATA [HYDRO_TEST_DATA]

{amplitude	frequency	cdyn	phase}
0.100000	1.000000	392.000000	1.900000
0.100000	2.000000	393.000000	3.800000
0.100000	3.000000	393.000000	4.800000
... continue
0.100000	40.000000	773.000000	4.700000
0.500000	1.000000	389.000000	2.800000
0.500000	2.000000	386.000000	4.100000
0.500000	3.000000	385.000000	5.800000
... continue
0.500000	40.000000	734.000000	4.800000
1.000000	1.000000	379.000000	3.100000
1.000000	2.000000	377.000000	4.800000
1.000000	3.000000	378.000000	6.900000
... continue
1.000000	40.000000	700.000000	4.700000

$OBJECTIVE_FUNCTION = 1.5051

$INTEGRATOR_ERROR = 0.0050

$STEADY_STATE_ERROR = 0.0100

$CONVERGENCE_TOLERANCE = 0.0050

$*** OPTIMIZATION ABORTED ***