Modelica.Mechanics.MultiBody.Interfaces

Connectors and partial models for 3-dim. mechanical components

Information

This package contains connectors and partial models (i.e., models that are only used to build other models) of the MultiBody library.

Extends from Modelica.Icons.InterfacesPackage (Icon for packages containing interfaces).

Package Content

Name	Description
Frame	Coordinate system fixed to the component with one cut-force and cut-torque (no icon)
Frame_a	Coordinate system fixed to the component with one cut-force and cut-torque (filled rectangular icon)
Frame_b	Coordinate system fixed to the component with one cut-force and cut-torque (non-filled rectangular icon)
Frame_resolve	Coordinate system fixed to the component used to express in which coordinate system a vector is resolved (non-filled rectangular icon)
FlangeWithBearing	Connector consisting of 1-dim. rotational flange and its bearing frame
FlangeWithBearingAdaptor	Adaptor to allow direct connections to the sub-connectors of FlangeWithBearing
PartialTwoFrames	Base model for components providing two frame connectors + outer world + assert to guarantee that the component is connected
PartialTwoFramesDoubleSize	Base model for components providing two frame connectors + outer world + assert to guarantee that the component is connected (default icon size is factor 2 larger as usual)
PartialOneFrame_a	Base model for components providing one frame_a connector + outer world + assert to guarantee that the component is connected
PartialOneFrame_b	Base model for components providing one frame_b connector + outer world + assert to guarantee that the component is connected
PartialElementaryJoint	Base model for elementary joints (has two frames + outer world + assert to guarantee that the joint is connected)
PartialForce	Base model for force elements (provide frame_b.f and frame_b.t in subclasses)
LineForceBase	Base model for line force elements
PartialLineForce	Base model for massless line force elements
PartialAbsoluteSensor	Base model to measure an absolute frame variable
PartialRelativeSensor	Base model to measure a relative variable between two frames
PartialVisualizer	Base model for visualizers (has a frame_a on the left side + outer world + assert to guarantee that the component is connected)
ZeroPosition	Set absolute position vector of frame_resolve to a zero vector and the orientation object to a null rotation
partialGravityAcceleration	Interface for the gravity function used in the World object
partialSurfaceCharacteristic	Interface for a function returning surface characteristics
partialColorMap	Interface for a function returning a color map

Modelica.Mechanics.MultiBody.Interfaces.Frame

Coordinate system fixed to the component with one cut-force and cut-torque (no icon)

Information

Basic definition of a coordinate system that is fixed to a mechanical component. In the origin of the coordinate system the cut-force and the cut-torque is acting. This component has no icon definition and is only used by inheritance from frame connectors to define different icons.

Contents

Modelica.Mechanics.MultiBody.Interfaces.Frame_a

Coordinate system fixed to the component with one cut-force and cut-torque (filled rectangular icon)

Information

Basic definition of a coordinate system that is fixed to a mechanical component. In the origin of the coordinate system the cut-force and the cut-torque is acting. This component has a filled rectangular icon.

Extends from Frame (Coordinate system fixed to the component with one cut-force and cut-torque (no icon)).

Contents

Modelica.Mechanics.MultiBody.Interfaces.Frame_b

Coordinate system fixed to the component with one cut-force and cut-torque (non-filled rectangular icon)

Information

Basic definition of a coordinate system that is fixed to a mechanical component. In the origin of the coordinate system the cut-force and the cut-torque is acting. This component has a non-filled rectangular icon.

Extends from Frame (Coordinate system fixed to the component with one cut-force and cut-torque (no icon)).

Contents

Modelica.Mechanics.MultiBody.Interfaces.Frame_resolve

Coordinate system fixed to the component used to express in which coordinate system a vector is resolved (non-filled rectangular icon)

Information

Basic definition of a coordinate system that is fixed to a mechanical component. In the origin of the coordinate system the cut-force and the cut-torque is acting. This coordinate system is used to express in which coordinate system a vector is resolved. A component that uses a Frame_resolve connector has to set the cut-force and cut-torque of this frame to zero. When connecting from a Frame_resolve connector to another frame connector, by default the connecting line has line style "dotted". This component has a non-filled rectangular icon.

Extends from Frame (Coordinate system fixed to the component with one cut-force and cut-torque (no icon)).

Contents

Modelica.Mechanics.MultiBody.Interfaces.FlangeWithBearing

Connector consisting of 1-dim. rotational flange and its bearing frame

Information

This hierarchical connector models a 1-dim. rotational flange connector and its optional bearing defined by a 3-dim. frame connector. If a connection to the subconnectors should be clearly visible, connect first an instance of FlangeWithBearingAdaptor to the FlangeWithBearing connector.

Parameters

Contents

Modelica.Mechanics.MultiBody.Interfaces.FlangeWithBearingAdaptor

Adaptor to allow direct connections to the sub-connectors of FlangeWithBearing

Information

Adaptor object to make a more visible connection to the flange and frame subconnectors of a FlangeWithBearing connector.

Parameters

Connectors

Modelica.Mechanics.MultiBody.Interfaces.PartialTwoFrames

Base model for components providing two frame connectors + outer world + assert to guarantee that the component is connected

Information

This partial model provides two frame connectors, access to the world object and an assert to check that both frame connectors are connected. Therefore, inherit from this partial model if the two frame connectors are needed and if the two frame connectors should be connected for a correct model.

Connectors

Modelica.Mechanics.MultiBody.Interfaces.PartialTwoFramesDoubleSize

Base model for components providing two frame connectors + outer world + assert to guarantee that the component is connected (default icon size is factor 2 larger as usual)

Information

This partial model provides two frame connectors, access to the world object and an assert to check that both frame connectors are connected. Therefore, inherit from this partial model if the two frame connectors are needed and if the two frame connectors should be connected for a correct model.

When dragging "PartialTwoFrames", the default size is a factor of two larger as usual. This partial model is used by the Joint.Assemblies joint aggregation models.

Connectors

Modelica.Mechanics.MultiBody.Interfaces.PartialOneFrame_a

Base model for components providing one frame_a connector + outer world + assert to guarantee that the component is connected

Information

This partial model provides one frame_a connector, access to the world object and an assert to check that the frame_a connector is connected. Therefore, inherit from this partial model if the frame_a connector is needed and if this connector should be connected for a correct model.

Connectors

Modelica.Mechanics.MultiBody.Interfaces.PartialOneFrame_b

Base model for components providing one frame_b connector + outer world + assert to guarantee that the component is connected

Information

This partial model provides one frame_b connector, access to the world object and an assert to check that the frame_b connector is connected. Therefore, inherit from this partial model if the frame_b connector is needed and if this connector should be connected for a correct model.

Connectors

Modelica.Mechanics.MultiBody.Interfaces.PartialElementaryJoint

Base model for elementary joints (has two frames + outer world + assert to guarantee that the joint is connected)

Information

All elementary joints should inherit from this base model, i.e., joints that are directly defined by equations, provided they compute either the rotation object of frame_b from the rotation object of frame_a and from relative quantities (or vice versa), or there is a constraint equation between the rotation objects of the two frames. In other cases, a joint object should inherit from Interfaces.PartialTwoFrames (e.g., joint Spherical, because there is no constraint between the rotation objects of frame_a and frame_b or joint Cylindrical because it is not an elementary joint).

This partial model provides two frame connectors, a "Connections.branch" between frame_a and frame_b, access to the world object and an assert to check that both frame connectors are connected.

Connectors

Modelica.Mechanics.MultiBody.Interfaces.PartialForce

Base model for force elements (provide frame_b.f and frame_b.t in subclasses)

Information

All 3-dimensional force and torque elements should be based on this superclass. This model defines frame_a and frame_b, computes the relative translation and rotation between the two frames and calculates the cut-force and cut-torque at frame_a by a force and torque balance from the cut-force and cut-torque at frame_b. As a result, in a subclass, only the relationship between the cut-force and cut-torque at frame_b has to be defined as a function of the following relative quantities:

r_rel_b[3]: Position vector from origin of frame_a to origin
            of frame_b, resolved in frame_b
R_rel     : Relative orientation object to rotate from frame_a to frame_b

Assume that force f = {100,0,0} should be applied on the body to which this force element is attached at frame_b, then the definition should be:

model Constant_x_Force
   extends Modelica.Mechanics.MultiBody.Interfaces.PartialForce;
equation
   frame_b.f = {-100, 0, 0};
   frame_b.t = zeros(3);
end Constant_x_Force;

Note, that frame_b.f and frame_b.t are flow variables and therefore the negative value of frame_b.f and frame_b.t is acting at the part to which this force element is connected.

Extends from PartialTwoFrames (Base model for components providing two frame connectors + outer world + assert to guarantee that the component is connected).

Connectors

Modelica.Mechanics.MultiBody.Interfaces.LineForceBase

Base model for line force elements

Information

All line force elements should be based on this base model. This model defines frame_a and frame_b and computes the (guarded) relative distance s. An assertion is raised if the relative distance length became smaller as parameter s_small.

Extends from PartialTwoFrames (Base model for components providing two frame connectors + outer world + assert to guarantee that the component is connected).

Parameters

Connectors

Modelica.Mechanics.MultiBody.Interfaces.PartialLineForce

Base model for massless line force elements

Information

All massless line force elements should be based on this base model. This model defines frame_a and frame_b, computes the (guarded) relative distance s and provides the force and torque balance of the cut-forces and cut-torques at frame_a and frame_b, respectively. In sub-models, only the line force f, acting at frame_b on the line from frame_a to frame_b, as a function of the relative distance s and its derivative der(s) has to be defined. Example:

model Spring
   parameter Real c "spring constant",
   parameter Real s_unstretched "unstretched spring length";
   extends Modelica.Mechanics.MultiBody.Interfaces.PartialLineForce;
equation
   f = c*(s-s_unstretched);
end Spring;

Extends from LineForceBase (Base model for line force elements).

Parameters

Connectors

Modelica.Mechanics.MultiBody.Interfaces.PartialAbsoluteSensor

Base model to measure an absolute frame variable

Information

This is the base class of a 3-dim. mechanics component with one frame and one output port in order to measure an absolute quantity in the frame connector and to provide the measured signal as output for further processing with the blocks of package Modelica.Blocks.

Extends from Modelica.Icons.RoundSensor (Icon representing a round measurement device).

Parameters

Connectors

Modelica.Mechanics.MultiBody.Interfaces.PartialRelativeSensor

Base model to measure a relative variable between two frames

Information

This is a base class for 3-dim. mechanical components with two frames and one output port in order to measure relative quantities between the two frames or the cut-forces/torques in the frame and to provide the measured signals as output for further processing with the blocks of package Modelica.Blocks.

Extends from Modelica.Icons.RoundSensor (Icon representing a round measurement device).

Parameters

Connectors

Modelica.Mechanics.MultiBody.Interfaces.PartialVisualizer

Base model for visualizers (has a frame_a on the left side + outer world + assert to guarantee that the component is connected)

Information

This partial model provides one frame_a connector, access to the world object and an assert to check that the frame_a connector is connected. It is used by inheritance from all visualizer objects.

Connectors

Modelica.Mechanics.MultiBody.Interfaces.ZeroPosition

Set absolute position vector of frame_resolve to a zero vector and the orientation object to a null rotation

Information

Element consisting of a frame (frame_resolve) that is fixed in the world frame and has it's position and orientation identical with the world, i.e. the position vector from origin of world frame to frame_resolve is zero vector and the relative orientation between those two frames is identity matrix.

This component provides no visualization.

Extends from Modelica.Blocks.Icons.Block (Basic graphical layout of input/output block).

Connectors

Modelica.Mechanics.MultiBody.Interfaces.partialGravityAcceleration

Interface for the gravity function used in the World object

Information

This partial function defines the interface to the gravity function used in the World object. All gravity field functions must inherit from this function. The input to the function is the absolute position vector of a point in the gravity field, whereas the output is the gravity acceleration at this point, resolved in the world frame.

Extends from Modelica.Icons.Function (Icon for functions).

Inputs

Outputs

Modelica.Mechanics.MultiBody.Interfaces.partialSurfaceCharacteristic

Interface for a function returning surface characteristics

Information

This partial function defines the interface of a function that returns surface characteristics for an object visualization, see e.g. Visualizers.Advanced.SurfaceCharacteristics.torus.

Extends from Modelica.Icons.Function (Icon for functions).

Inputs

Outputs

Modelica.Mechanics.MultiBody.Interfaces.partialColorMap

Interface for a function returning a color map

Information

This partial function defines the interface of a function that returns a color map. Predefined color map functions are defined in package Modelica.Mechanics.MultiBody.Visualizers.Colors.ColorMaps.

Extends from Modelica.Icons.Function (Icon for functions).

Inputs

Outputs