The LoadTypeis for describing loads mounted on the motion device typically by an integrator or a customer and is formally defined in Table 47. Instances of this ObjectTypedefinition are used to describe the load mounted on one of several mounting points. A very common mounting point is the flange of a motion device. Typically a motion device has additional mounting points on some of the axis. The provided values can either be determined by the robot controller or can be set up by an operator.

image032.png

Figure 23– Overview LoadType

Table 47– LoadType Definition

Attribute

Value

BrowseName

LoadType

IsAbstract

False

References

Node Class

BrowseName

DataType

TypeDefinition

Modelling Rule

Subtype of the BaseObjectType defined in OPC Unified Architecture

HasComponent

Variable

Mass

Double

AnalogUnitType

Mandatory

HasComponent

Variable

CenterOfMass

3DFrame

3DFrameType

Optional

HasComponent

Variable

Inertia

3DVector

3DVectorType

Optional

The variable Massprovides the weight of the load mounted on one mounting point.

The EngineeringUnitsof the Massshall be provided.

The variable CenterOfMassprovides the position and orientation of the center of the mass related to the mounting point using a 3DFrameType. X, Y, Z define the position of the center of gravity relative to the mounting point coordinate system. A, B, C define the orientation of the principal axes of inertia relative to the mounting point coordinate system. Orientation A, B, C can be "0" for systems which do not need these values.

3DFrameTypeand 3DFrame are defined in OPC 10001-11 (SpatialTypes).

If the instance of the LoadTypedescribes the flange load of a motion device the mounting point coordinate system is the flange coordinate system. If the instance of the LoadTypedescribes an additional load of an axis the mounting point coordinate system is vendor specific and it is up to the vendor to model this coordinate system.

The variable Inertiauses the 3DVektorTypeto describe the three values of the principal moments of inertia with respect to the mounting point coordinate system. If inertia values are provided for rotary axis the CenterOfMassshall be completely filled as well. Table 48describes the possible degrees of modelling from a minimal one e.g. only the weight of the mass to a complete one comprising weight, center of mass, principal axes and inertia.

3DVectorTypeand 3DVector are defined in OPC 10001-11 (SpatialTypes).

Table 48– LoadType possible degrees of modelling

Mass

CenterOfMass

Inertia

X, Y, Z

A, B, C

Mass only

Used

-

-

-

Mass with center of gravity

Used

Used

0, 0, 0

-

Mass with inertia

Used

Used

Used

Used