Modelica.Mechanics.Translational.Interfaces

Information

This package contains connectors and partial models for 1-dim. translational mechanical components. The components of this package can only be used as basic building elements for models.

Package Content

Name	Description
Flange_a	(left) 1D translational flange (flange axis directed INTO cut plane, e. g. from left to right)
Flange_b	(right) 1D translational flange (flange axis directed OUT OF cut plane)
Support	Support/housing 1D translational flange
InternalSupport	Adapter model to utilize conditional support connector
PartialTwoFlanges	Component with two translational 1D flanges
PartialOneFlangeAndSupport	Partial model for a component with one translational 1-dim. shaft flange and a support used for graphical modeling, i.e., the model is build up by drag-and-drop from elementary components
PartialTwoFlangesAndSupport	Partial model for a component with two translational 1-dim. shaft flanges and a support used for graphical modeling, i.e., the model is build up by drag-and-drop from elementary components
PartialRigid	Rigid connection of two translational 1D flanges
PartialCompliant	Compliant connection of two translational 1D flanges
PartialCompliantWithRelativeStates	Base model for the compliant connection of two translational 1-dim. shaft flanges where the relative position and relative velocities are used as states
PartialElementaryOneFlangeAndSupport	Obsolete partial model. Use PartialElementaryOneFlangeAndSupport2.
PartialElementaryOneFlangeAndSupport2	Partial model for a component with one translational 1-dim. shaft flange and a support used for textual modeling, i.e., for elementary models
PartialElementaryTwoFlangesAndSupport	Obsolete partial model. Use PartialElementaryTwoFlangesAndSupport2.
PartialElementaryTwoFlangesAndSupport2	Partial model for a component with one translational 1-dim. shaft flange and a support used for textual modeling, i.e., for elementary models
PartialElementaryRotationalToTranslational	Partial model to transform rotational into translational motion
PartialForce	Partial model of a force acting at the flange (accelerates the flange)
PartialAbsoluteSensor	Device to measure a single absolute flange variable
PartialRelativeSensor	Device to measure a single relative variable between two flanges
PartialFriction	Base model of Coulomb friction elements

Modelica.Mechanics.Translational.Interfaces.Flange_a

Information

This is a flange for 1D translational mechanical systems. In the cut plane of the flange a unit vector n, called flange axis, is defined which is directed INTO the cut plane, i. e. from left to right. All vectors in the cut plane are resolved with respect to this unit vector. E.g. force f characterizes a vector which is directed in the direction of n with value equal to f. When this flange is connected to other 1D translational flanges, this means that the axes vectors of the connected flanges are identical.

The following variables are transported through this connector:

  s: Absolute position of the flange in [m]. A positive translation
     means that the flange is translated along the flange axis.
  f: Cut-force in direction of the flange axis in [N].

Contents

Name	Description
s	Absolute position of flange [m]
f	Cut force directed into flange [N]

Modelica.Mechanics.Translational.Interfaces.Flange_b

Information

This is a flange for 1D translational mechanical systems. In the cut plane of the flange a unit vector n, called flange axis, is defined which is directed OUT OF the cut plane. All vectors in the cut plane are resolved with respect to this unit vector. E.g. force f characterizes a vector which is directed in the direction of n with value equal to f. When this flange is connected to other 1D translational flanges, this means that the axes vectors of the connected flanges are identical.

The following variables are transported through this connector:

  s: Absolute position of the flange in [m]. A positive translation
     means that the flange is translated along the flange axis.
  f: Cut-force in direction of the flange axis in [N].

Contents

Name	Description
s	Absolute position of flange [m]
f	Cut force directed into flange [N]

Modelica.Mechanics.Translational.Interfaces.Support

Information

This is a connector for 1-dim. rotational mechanical systems and models the support or housing of a shaft. The following variables are defined in this connector:

The support connector is usually defined as conditional connector. It is most convenient to utilize it

• For models to be build graphically (i.e., the model is build up by drag-and-drop from elementary components):
  PartialOneFlangeAndSupport,
  PartialTwoFlangesAndSupport,
   
• For models to be build textually (i.e., elementary models):
  PartialElementaryOneFlangeAndSupport,
  PartialElementaryTwoFlangesAndSupport,
  PartialElementaryRotationalToTranslational.

Contents

Name	Description
s	Absolute position of flange [m]
f	Cut force directed into flange [N]

Modelica.Mechanics.Translational.Interfaces.InternalSupport

Information

This is an adapter model to utilize a conditional support connector in an elementary component, i.e., where the component equations are defined textually:

• If useSupport = true, the flange has to be connected to the conditional support connector.
• If useSupport = false, the flange has to be connected to the conditional fixed model.

Variable f is defined as input and must be provided when using this component as a modifier (computed via a force balance in the model where InternalSupport is used). Usually, model InternalSupport is utilized via the partial models:

PartialElementaryOneFlangeAndSupport,
PartialElementaryTwoFlangesAndSupport,
PartialElementaryRotationalToTranslational.

Note, the support position can always be accessed as internalSupport.s, and the support force can always be accessed as internalSupport.f.

Connectors

Name	Description
flange	Internal support flange (must be connected to the conditional support connector for useSupport=true and to conditional fixed model for useSupport=false)

Modelica.Mechanics.Translational.Interfaces.PartialTwoFlanges

Information

This is a 1D translational component with two flanges. It is used e.g., to built up parts of a drive train consisting of several base components.

Connectors

Name	Description
flange_a	(left) driving flange (flange axis directed in to cut plane, e. g. from left to right)
flange_b	(right) driven flange (flange axis directed out of cut plane)

Modelica.Mechanics.Translational.Interfaces.PartialOneFlangeAndSupport

Information

This is a 1-dim. translational component with one flange and a support/housing. It is used e.g., to build up parts of a drive train graphically consisting of several components.

If useSupport=true, the support connector is conditionally enabled and needs to be connected.
If useSupport=false, the support connector is conditionally disabled and instead the component is internally fixed to ground.

Parameters

Name	Description
useSupport	= true, if support flange enabled, otherwise implicitly grounded

Connectors

Name	Description
flange	Flange of component
support	Support/housing of component

Modelica.Mechanics.Translational.Interfaces.PartialTwoFlangesAndSupport

Information

This is a 1-dim. translational component with two flanges and a support/housing. It is used e.g., to build up parts of a drive train graphically consisting of several components.

If useSupport=true, the support connector is conditionally enabled and needs to be connected.
If useSupport=false, the support connector is conditionally disabled and instead the component is internally fixed to ground.

Parameters

Name	Description
useSupport	= true, if support flange enabled, otherwise implicitly grounded

Connectors

Name	Description
flange_a	Flange of left end
flange_b	Flange of right end
support	Support/housing of component

Modelica.Mechanics.Translational.Interfaces.PartialRigid

Information

This is a 1-dim. translational component with two rigidly connected flanges. The fixed distance between the left and the right flange is defined by parameter "L". The forces at the right and left flange can be different. It is used e.g., to built up sliding masses.

Parameters

Name	Description
L	Length of component, from left flange to right flange (= flange_b.s - flange_a.s) [m]

Connectors

Name	Description
flange_a	Left flange of translational component
flange_b	Right flange of translational component

Modelica.Mechanics.Translational.Interfaces.PartialCompliant

Information

This is a 1D translational component with a compliant connection of two translational 1D flanges where inertial effects between the two flanges are not included. The absolute value of the force at the left and the right flange is the same. It is used to built up springs, dampers etc.

Connectors

Name	Description
flange_a	Left flange of compliant 1-dim. translational component
flange_b	Right flange of compliant 1-dim. translational component

Modelica.Mechanics.Translational.Interfaces.PartialCompliantWithRelativeStates

Information

This is a 1-dim. translational component with a compliant connection of two translational 1-dim. flanges where inertial effects between the two flanges are neglected. The basic assumption is that the cut-forces of the two flanges sum-up to zero, i.e., they have the same absolute value but opposite sign: flange_a.f + flange_b.f = 0. This base class is used to built up force elements such as springs, dampers, friction.

The difference to base class "PartialCompliant" is that the relative distance and the relative velocity are defined as preferred states. The reason is that for a large class of drive trains, the absolute position is quickly increasing during operation. Numerically, it is better to use relative distances between drive train components because they remain in a limited size. For this reason, StateSelect.prefer is set for the relative distance of this component.

In order to improve the numerics, a nominal value for the relative distance should be set, since drive train distances are in a small order and then step size control of the integrator is practically switched off for such a variable. A default nominal value of s_nominal = 1e-4 is defined. This nominal value might also be computed from other values, such as "s_nominal = f_nominal / c" for a spring, if f_nominal and c have more meaningful values for the user.

Parameters

Name	Description
Advanced
stateSelect	Priority to use phi_rel and w_rel as states
s_nominal	Nominal value of s_rel (used for scaling) [m]

Connectors

Name	Description
flange_a	Left flange of compliant 1-dim. translational component
flange_b	Right flange of compliant 1-dim. translational component

Modelica.Mechanics.Translational.Interfaces.PartialElementaryOneFlangeAndSupport

Information

This is a 1-dim. translational component with one flange and a support/housing. It is used to build up elementary components of a drive train with equations in the text layer.

If useSupport=true, the support connector is conditionally enabled and needs to be connected.
If useSupport=false, the support connector is conditionally disabled and instead the component is internally fixed to ground.

Parameters

Name	Description
useSupport	= true, if support flange enabled, otherwise implicitly grounded

Connectors

Name	Description
flange	Flange of component
support	Support/housing of component

Modelica.Mechanics.Translational.Interfaces.PartialElementaryOneFlangeAndSupport2

Information

This is a 1-dim. translational component with one flange and a support/housing. It is used to build up elementary components of a drive train with equations in the text layer.

If useSupport=true, the support connector is conditionally enabled and needs to be connected.
If useSupport=false, the support connector is conditionally disabled and instead the component is internally fixed to ground.

Parameters

Name	Description
useSupport	= true, if support flange enabled, otherwise implicitly grounded

Connectors

Name	Description
flange	Flange of component
support	Support/housing of component

Modelica.Mechanics.Translational.Interfaces.PartialElementaryTwoFlangesAndSupport

Information

This is a 1-dim. translational component with two flanges and an additional support. It is used e.g., to build up elementary ideal gear components. The component contains the force balance, i.e., the sum of the forces of the connectors is zero (therefore, components that are based on PartialGear cannot have a mass). The support connector needs to be connected to avoid the unphysical behavior that the support force is required to be zero (= the default value, if the connector is not connected).

Parameters

Name	Description
useSupport	= true, if support flange enabled, otherwise implicitly grounded

Connectors

Name	Description
flange_a	Flange of left shaft
flange_b	Flange of right shaft
support	Support/housing of component

Modelica.Mechanics.Translational.Interfaces.PartialElementaryTwoFlangesAndSupport2

Information

This is a 1-dim. translational component with two flanges and an additional support. It is used e.g., to build up elementary ideal gear components. The component contains the force balance, i.e., the sum of the forces of the connectors is zero (therefore, components that are based on PartialGear cannot have a mass). The support connector needs to be connected to avoid the unphysical behavior that the support force is required to be zero (= the default value, if the connector is not connected).

Parameters

Name	Description
useSupport	= true, if support flange enabled, otherwise implicitly grounded

Connectors

Name	Description
flange_a	Flange of left shaft
flange_b	Flange of right shaft
support	Support/housing of component

Modelica.Mechanics.Translational.Interfaces.PartialElementaryRotationalToTranslational

Information

This is a 1-dim. rotational component with

• one rotational flange,
• one rotational support/housing,
• one translational flange, and
• one translational support/housing

This model is used to build up elementary components of a drive train transforming rotational into translational motion with equations in the text layer.

If useSupportR=true, the rotational support connector is conditionally enabled and needs to be connected.

If useSupportR=false, the rotational support connector is conditionally disabled and instead the rotational part is internally fixed to ground.

If useSupportT=true, the translational support connector is conditionally enabled and needs to be connected.

If useSupportT=false, the translational support connector is conditionally disabled and instead the translational part is internally fixed to ground.

Parameters

Name	Description
useSupportR	= true, if rotational support flange enabled, otherwise implicitly grounded
useSupportT	= true, if translational support flange enabled, otherwise implicitly grounded

Connectors

Name	Description
flangeR	Flange of rotational shaft
flangeT	Flange of translational rod
supportR	Rotational support/housing of component
supportT	Translational support/housing of component

Modelica.Mechanics.Translational.Interfaces.PartialForce

Information

Partial model of force that accelerates the flange.

If useSupport=true, the support connector is conditionally enabled and needs to be connected.
If useSupport=false, the support connector is conditionally disabled and instead the component is internally fixed to ground.

Parameters

Name	Description
useSupport	= true, if support flange enabled, otherwise implicitly grounded

Connectors

Name	Description
flange	Flange of component
support	Support/housing of component

Modelica.Mechanics.Translational.Interfaces.PartialAbsoluteSensor

Information

This is the superclass of a 1D translational component with one flange and one output signal in order to measure an absolute kinematic quantity in the flange and to provide the measured signal as output signal for further processing with the Modelica.Blocks blocks.

Connectors

Name	Description
flange	Flange to be measured (flange axis directed in to cut plane, e. g. from left to right)

Modelica.Mechanics.Translational.Interfaces.PartialRelativeSensor

Information

This is a superclass for 1D translational components with two rigidly connected flanges and one output signal in order to measure relative kinematic quantities between the two flanges or the cut-force in the flange and to provide the measured signal as output signal for further processing with the Modelica.Blocks blocks.

Connectors

Name	Description
flange_a	(left) driving flange (flange axis directed in to cut plane, e. g. from left to right)
flange_b	(right) driven flange (flange axis directed out of cut plane)

Modelica.Mechanics.Translational.Interfaces.PartialFriction

Information

Basic model for Coulomb friction that models the stuck phase in a reliable way.

Parameters

Name	Description
Advanced
v_small	Relative velocity near to zero (see model info text) [m/s]