SIMVehiclesSubmodules

Suspension submodule

Use suspension parameters to define springs, dampers, anti-roll bars, stops, kinematics, compliance, setup values, and unsprung mass properties.

Suspension defines springs, dampers, anti-roll bars, bump rubbers, rebound stops, kinematics, compliance, static setup values, and unsprung mass properties. Vehicles select separate front and rear suspension modules.

When to use it

Use suspension when you need a reusable setup building block that can be selected in a vehicle assembly. Create and maintain it from Design > Suspensions, then select it in the vehicle slot Suspension Front and Suspension Rear.

How it fits vehicle setup

  1. Create or duplicate the submodule from the Design section.
  2. Open the submodule row to review and edit parameter values.
  3. Save changes with Update Data.
  4. Open Vehicles and select the submodule in Vehicle Assembly.
  5. Use the vehicle detail tabs to inspect the selected submodule inside the vehicle context.

You need module create permission to create a new submodule and module update permission to edit values.

Parameter reference

Units, defaults, and ranges show n/a when no stable user-facing value was verified in the source used for this page. Method rows control which constant, lookup table, or polynomial rows are active in the product table.

Spring

ParameterDescriptionUnitsDefaultValidation / Range
PreloadThe ride spring preload force.Nn/an/a
Force GainA gain that can be used to amplify the spring force. This gain is applicable for all the scenarios; spring stiffness as a constant value, spring force as a polynomial or spring force from a lookup table. A gain higher than 1 will increase the spring force. A gain less than 1 will reduce the spring force.n/an/an/a
MethodSelect in what way the spring stiffness shall be described and modeled, as a simple constant value, as a lookup table or by using polynomial functions.n/an/aSelects active input method
Constant StiffnessThe ride spring linear stiffness as a constant value.N/mmn/aVisible when method = Constant
Lookup TableThe lookup table gives the opportunity to freely define the relationship between the spring force vs travel.N/mmn/aVisible when method = LookupTable
Lookup Table RightLookup table for force vs travel (right).N/mmn/aVisible when method = LookupTable
MethodSelect in what way the motion ratio shall be described and modeled, as a simple constant value, as a lookup table or by using polynomial functions.n/an/aSelects active input method
Constant Motion RatioThe ride spring constant motion ratio. Motion ratio higher than 1 means that the spring travel is higher than the wheel travel. Motion ratio lower than 1 means that the spring travel is less than the wheel travel.n/an/aVisible when method = Constant
Lookup TableThe lookup table gives the opportunity to freely define the relationship between the spring travel and the wheel travel. Positive spring travel means elongation. Positive wheel travel means rebound.n/an/aVisible when method = LookupTable
Lookup Table RightLookup table for motion ratio (right).n/an/aVisible when method = LookupTable

Anti-roll bar

ParameterDescriptionUnitsDefaultValidation / Range
Force GainA gain that can be used to amplify the antiroll bar force. This gain is applicable for all the scenarios; antiroll bar stiffness as a constant value, antiroll bar force as a polynomial or antiroll bar force from a lookup table. A gain higher than 1 will increase the antiroll bar force. A gain less than 1 will reduce the antiroll bar force.n/an/an/a
MethodSelect in what way the antiroll bar stiffness shall be described and modeled, as a simple constant value, as a lookup table or by using polynomial functions.n/an/aSelects active input method
Constant StiffnessThe antiroll bar linear stiffness as a constant value. This is the stiffness measured at the wheel.N/mmn/aVisible when method = Constant
Lookup TableThe lookup table gives the opportunity to freely define the relationship between the antiroll bar force vs wheel travel.N/mmn/aVisible when method = LookupTable

Bump rubber

ParameterDescriptionUnitsDefaultValidation / Range
ClearanceThe distance, at design position, that the damper has to travel until the bump rubber is engaged. It is assumed that the bump rubber is placed on the damper and therefore has the same motion ratio as the damper.mmn/an/a
Force GainA gain that can be used to amplify the bump rubber force. This gain is applicable for all the scenarios; bump rubber stiffness as a constant value, bump rubber force as a polynomial or bump rubber force from a lookup table. A gain higher than 1 will increase the bump rubber force. A gain less than 1 will reduce the bump rubber force.n/an/an/a
MethodSelect in what way the bump rubber stiffness shall be described and modeled, as a simple constant value, as a lookup table or by using polynomial functions.n/an/aSelects active input method
Constant StiffnessThe bump rubber linear stiffness as a constant value.N/mmn/aVisible when method = Constant
Lookup TableThe lookup table gives the opportunity to freely define the relationship between the bump rubber force vs travel.N/mmn/aVisible when method = LookupTable
Lookup Table RightLookup table for bump rubber force vs travel (right).N/mmn/aVisible when method = LookupTable

Rebound stop

ParameterDescriptionUnitsDefaultValidation / Range
ClearanceThe distance, at design position, that the damper has to travel until the rebound stop is engaged. It is assumed that the rebound stop is placed on the damper and therefore has the same motion ratio as the damper.mmn/an/a
Force GainA gain that can be used to amplify the rebound stop force. This gain is applicable for all the scenarios; rebound stop stiffness as a constant value, rebound stop force as a polynomial or bump rebound stop force from a lookup table. A gain higher than 1 will increase the rebound stop force. A gain less than 1 will reduce the rebound stop force.n/an/an/a
MethodSelect in what way the rebound stop stiffness shall be described and modeled, as a simple constant value, as a lookup table or by using polynomial functions.n/an/aSelects active input method
Constant StiffnessThe rebound stop linear stiffness as a constant value.N/mmn/aVisible when method = Constant
Lookup TableThe lookup table gives the opportunity to freely define the relationship between the rebound stop force vs travel.N/mmn/aVisible when method = LookupTable
Lookup Table RightLookup table for rebound stop force vs travel (right).N/mmn/aVisible when method = LookupTable

Damper

ParameterDescriptionUnitsDefaultValidation / Range
PreloadThe damper preload force.Nn/an/a
Force Gain CompressionA gain that can be used to scale the damping force on the compression side.n/an/an/a
Force Gain ReboundA gain that can be used to scale the damping force on the rebound side.n/an/an/a
MethodSelect in what way the damping rates shall be described and modeled, as a simple constant values for the damping rates and the transition points between the different regions or as a lookup tables.n/an/aSelects active input method
Rate - Comp Low SpeedThe damping rate coefficient for the compression, low speed section.Ns/mmn/aVisible when method = Constant
Rate - Comp Medium SpeedThe damping rate coefficient for the compression, medium speed section.Ns/mmn/aVisible when method = Constant
Rate - Comp High SpeedThe damping rate coefficient for the compression, high speed section.Ns/mmn/aVisible when method = Constant
Rate - Reb Low SpeedThe damping rate coefficient for the rebound, low speed section.Ns/mmn/aVisible when method = Constant
Rate - Reb Medium SpeedThe damping rate coefficient for the rebound, medium speed section.Ns/mmn/aVisible when method = Constant
Rate - Reb High SpeedThe damping rate coefficient for the rebound, high speed section.Ns/mmn/aVisible when method = Constant
Transition - Comp Low to MediumThe damping force at which the transition between compression low speed and compression medium speed is defined.Nn/aVisible when method = Constant
Transition - Comp Medium to HighThe damping force at which the transition between compression medium speed and compression high speed is defined.Nn/aVisible when method = Constant
Transition - Reb Low to MediumThe damping force at which the transition between rebound low speed and rebound medium speed is defined.Nn/aVisible when method = Constant
Transition - Reb Medium to HighThe damping force at which the transition between rebound medium speed and rebound high speed is defined.Nn/aVisible when method = Constant
Lookup tableThe lookup table gives the opportunity to freely define the relationship between the damper force vs travel.Ns/mmn/aVisible when method = LookupTable
Lookup Table RightLookup table for force vs velocity (right).Ns/mmn/aVisible when method = LookupTable
MethodSelect in what way the damper motion ratio shall be described and modeled, as a simple constant value, as a lookup table or by using polynomial functions.n/an/aSelects active input method
Constant Motion RatioThe damper constant motion ratio. Motion ratio higher than 1 means that the damper travel is higher than the wheel travel. Motion ratio lower than 1 means that the damper travel is less than the wheel travel.n/an/aVisible when method = Constant
Lookup tableThe lookup table gives the opportunity to freely define the relationship between the damper travel and the wheel travel. Positive damper travel means elongation. Positive wheel travel means rebound.n/an/aVisible when method = LookupTable
Motion Ratio Right Lookup TableThe lookup table gives the opportunity to freely define the relationship between the damper travel and the wheel travel. Positive damper travel means elongation. Positive wheel travel means rebound.n/an/aVisible when method = LookupTable

Third spring

ParameterDescriptionUnitsDefaultValidation / Range
PreloadThe 3rd spring preload force.Nn/an/a
Force GainA gain that can be used to amplify the 3rd spring force. This gain is applicable for all the scenarios; spring stiffness as a constant value, spring force as a polynomial or spring force from a lookup table. A gain higher than 1 will increase the spring force. A gain less than 1 will reduce the spring force.n/an/an/a
MethodSelect in what way the spring stiffness shall be described and modeled, as a simple constant value, as a lookup table or by using polynomial functions.n/an/aSelects active input method
Constant StiffnessThe 3rd spring linear stiffness as a constant value.N/mmn/aVisible when method = Constant
Lookup TableThe lookup table gives the opportunity to freely define the relationship between the 3rd spring force vs travel.N/mmn/aVisible when method = LookupTable
MethodSelect in what way the motion ratio shall be described and modeled, as a simple constant value, as a lookup table or by using polynomial functions.n/an/aSelects active input method
Constant Motion RatioThe 3rd spring constant motion ratio. Motion ratio higher than 1 means that the spring travel is higher than the wheel travel. Motion ratio lower than 1 means that the spring travel is less than the wheel travel.-n/aVisible when method = Constant
Lookup tableThe lookup table gives the opportunity to freely define the relationship between the 3rd spring travel and the average left and right wheel travel. Positive spring travel means elongation. Positive wheel travel means rebound.-n/aVisible when method = LookupTable

Third bump rubber

ParameterDescriptionUnitsDefaultValidation / Range
ClearanceThe distance, at design position, that the 3rd damper has to travel until the bump rubber is engaged. It is assumed that the bump rubber is placed on the damper and therefore has the same motion ratio as the damper.mmn/an/a
Force GainA gain that can be used to amplify the 3rd bump rubber force. This gain is applicable for all the scenarios; bump rubber stiffness as a constant value, bump rubber force as a polynomial or bump rubber force from a lookup table. A gain higher than 1 will increase the bump rubber force. A gain less than 1 will reduce the bump rubber force.n/an/an/a
MethodSelect in what way the bump rubber stiffness shall be described and modeled, as a simple constant value, as a lookup table or by using polynomial functions.n/an/aSelects active input method
Constant StiffnessThe 3rd bump rubber linear stiffness as a constant value.N/mmn/aVisible when method = Constant
Lookup TableThe lookup table gives the opportunity to freely define the relationship between the 3rd bump rubber force vs travel.N/mmn/aVisible when method = LookupTable

Third damper

ParameterDescriptionUnitsDefaultValidation / Range
PreloadThe 3rd damper preload force.Nn/an/a
Force Gain CompressionA gain that can be used to scale the 3rd damper damping force on the compression side.n/an/an/a
Force Gain ReboundA gain that can be used to scale the 3rd damper damping force on the rebound side.n/an/an/a
MethodSelect in what way the damping rates shall be described and modeled, as a simple constant values for the damping rates and the transition points between the different regions or as a lookup tables.n/an/aSelects active input method
Rate - Comp Low SpeedThe 3rd damper damping rate coefficient for the compression, low speed section.Ns/mmn/aVisible when method = Constant
Rate - Comp Medium SpeedThe 3rd damper damping rate coefficient for the compression, medium speed section.Ns/mmn/aVisible when method = Constant
Rate - Comp High SpeedThe 3rd damper damping rate coefficient for the compression, high speed section.Ns/mmn/aVisible when method = Constant
Rate - Reb Low SpeedThe 3rd damper damping rate coefficient for the rebound, low speed section.Ns/mmn/aVisible when method = Constant
Rate - Reb Medium SpeedThe 3rd damper damping rate coefficient for the rebound, medium speed section.Ns/mmn/aVisible when method = Constant
Rate - Reb High SpeedThe 3rd damper damping rate coefficient for the rebound, high speed section.Ns/mmn/aVisible when method = Constant
Transition - Comp Low to MediumThe 3rd damper damping force at which the transition between compression low speed and compression medium speed is defined.Nn/aVisible when method = Constant
Transition - Comp Medium to HighThe 3rd damper damping force at which the transition between compression medium speed and compression high speed is defined.Nn/aVisible when method = Constant
Transition - Reb Low to MediumThe 3rd damper damping force at which the transition between rebound low speed and rebound medium speed is defined.Nn/aVisible when method = Constant
Transition - Reb Medium to HighThe 3rd damper damping force at which the transition between rebound medium speed and rebound high speed is defined.Nn/aVisible when method = Constant
Lookup tableThe lookup table gives the opportunity to freely define the relationship between the 3rd damper force vs travel.Ns/mmn/aVisible when method = LookupTable
MethodSelect in what way the damper motion ratio shall be described and modeled, as a simple constant value, as a lookup table or by using polynomial functions.n/an/aSelects active input method
Constant Motion RatioThe 3rd damper constant motion ratio. Motion ratio higher than 1 means that the damper travel is higher than the wheel travel. Motion ratio lower than 1 means that the damper travel is less than the wheel travel.n/an/aVisible when method = Constant
Lookup tableThe lookup table gives the opportunity to freely define the relationship between the 3rd damper travel and the average left and right wheel travel. Positive damper travel means elongation. Positive wheel travel means rebound.n/an/aVisible when method = LookupTable

Kinematics

ParameterDescriptionUnitsDefaultValidation / Range
Polynomial LeftThird order polynomial coefficients to define the toe angle vs wheel travel. toeAngle = toeAngleStatic + c1 _ travelWheel + c2 _ travelWheel^2 + c3 * travelWheel^3. A positive toe angle is when the front end of the wheel is closer to the center of the car than the rear (toe-in).°/mmn/ac0 fixed at 0
Polynomial RightThird order polynomial coefficients to define the toe angle vs wheel travel. toeAngle = toeAngleStatic + c1 _ travelWheel + c2 _ travelWheel^2 + c3 * travelWheel^3. A positive toe angle is when the front end of the wheel is closer to the center of the car than the rear (toe-in).°/mmn/ac0 fixed at 0
Polynomial LeftThird order polynomial coefficients to define the camber angle vs wheel travel. tcamberAngle = camberAngleStatic + c1 _ travelWheel + c2 _ travelWheel^2 + c3 * travelWheel^3. A positive camber angle is when the top of the wheel is further away from the center of the car than the bottom part.°/mmn/ac0 fixed at 0
Polynomial RightThird order polynomial coefficients to define the camber angle vs wheel travel. tcamberAngle = camberAngleStatic + c1 _ travelWheel + c2 _ travelWheel^2 + c3 * travelWheel^3. A positive camber angle is when the top of the wheel is further away from the center of the car than the bottom part.°/mmn/ac0 fixed at 0
MethodSelect in what way the front view swing arm angle shall be described and modeled, as a simple constant value, as a lookup table or by using polynomial functions.n/an/aSelects active input method
ConstantThe constant value of the inclination angle in the front view between the ground plane and the virtual line between the tyre contact patch and the instantaneous center of rotation. This defines the anti-roll and jacking effect. It relates to the roll center in the static position.°n/aVisible when method = Constant
Polynomial LeftThird order polynomial coefficients to define the front view swing arm angle vs wheel travel. frontViewSwingArmAngle = frontViewSwingArmAngleStatic + c1 _ travelWheel + c2 _ travelWheel^2 + c3 * travelWheel^3. A positive front view swing arm angle is when the virtual line points upward from the tyre contact patch towards the car. A positive wheel travel is when the wheel is moving in rebound.°/mmn/ac0 fixed at 0
Polynomial RightThird order polynomial coefficients to define the front view swing arm angle vs wheel travel. frontViewSwingArmAngle = frontViewSwingArmAngleStatic + c1 _ travelWheel + c2 _ travelWheel^2 + c3 * travelWheel^3. A positive front view swing arm angle is when the virtual line points upward from the tyre contact patch towards the car. A positive wheel travel is when the wheel is moving in rebound.°/mmn/ac0 fixed at 0

Setup

ParameterDescriptionUnitsDefaultValidation / Range
Ride HeightThe vertical distance between the ground and the chosen measurement point on the sprung body.mmn/an/a
Corner WeightThe corner load of the car as if being measured on four scales under the car.kgn/an/a
Toe AngleThe static toe angle of the wheel at design position. A positive toe angle is when the front end of the wheel is closer to the center of the car than the rear (toe-in).°n/an/a
Camber AngleThe static camber angle of the wheel at design position. A positive camber angle is when the top of the wheel is further away from the center of the car than the bottom part.°n/an/a

Misc

ParameterDescriptionUnitsDefaultValidation / Range
Track WidthThe distance between the points where the left and right wheel center planes, that are normal to the wheel spin axis, intersects with the ground.mmn/an/a
3rd Element EnabledOption to select if the suspension should have the third element (spring/damper/bump rubber) enabled or disabled.n/an/an/a
Wheel Spin InertiaThe inertia of the complete rotating mass around the spin axis. Tyre, wheel, hub, brake disc and brake disc bell etc.kgm²n/an/a
Unsprung WeightThe weight of the unsprung mass. This is typically everything on the wheel side of the suspension plus half of all the suspension elements and the drive shafts.kgn/an/a
Unsprung CoG HeightThe vertical distance from the ground at the design position of the unsprung weight.mmn/an/a
Unsprung Mass IxxThe diagonal term of the inertia tensor of the unsprung mass denoting the inertia around the x axis.kgm²n/an/a
Unsprung Mass IyyThe diagonal term of the inertia tensor of the unsprung mass denoting the inertia around the y axis.kgm²n/an/a
Unsprung Mass IzzThe diagonal term of the inertia tensor of the unsprung mass denoting the inertia around the z axis.kgm²n/an/a
Unsprung Mass IxyThe off-diagonal term of the inertia tensor of the unsprung mass denoting the inertia around the y-axis when the assembly is rotated around the x-axis.kgm²n/an/a
Unsprung Mass IyzThe off-diagonal term of the inertia tensor of the unsprung mass denoting the inertia around the z-axis when the assembly is rotated around the y-axis.kgm²n/an/a
Unsprung Mass IxzThe off-diagonal term of the inertia tensor of the unsprung mass denoting the inertia around the z-axis when the assembly is rotated around the x-axis.kgm²n/an/a

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