Capability Summary
Basic Feature
The basic feature is the possibility to create a logical reference from a physical mechanism, and a corresponding logical-physical link. This enables the communication between physical products and logical components. An important outcome is the ability to link a physical mechanism to a Modelica behavior.
Graphical User Interface
You use a specific interface to define the communication, for example:
- Selecting simulation mode
- Selecting what physical objects that are to be a part of the communication with logical components
- Creating the dedicated logical reference including the logical-physical mapping in that componentNote: If a suitable logical reference is already available, you can create the logical-physical mapping in that reference.
- Editing the connections between logical signals and mechanical signals.
Simulation
When the connections between physical products and logical components have been set up, the model can be simulated. You can use the Behavior Selection command to select either the behavior coming from the physical definition of the model, or the dynamic Modelica behavior. See Selecting a Behavior in a Multi-Behavior Model.
Simulation Modes
You can define the simulation to be in any of:
- Kinematic mode
- Dynamic mode driven by position commands (angle or length)
- Dynamic mode driven by force commands
Important:
|
- Contacts are taken into account
- By default, the gravity is
(0; 0; -9,81ms-1) - If input commands are not allowed by the mechanism because of, for example, they are outside of mechanical authorized bounds or because of contact problems, the simulation performance can be strongly limited.
Simulation Features
Some features of the simulation:
- You can simulate the mechanical behavior with the other behaviors. If you select only the mechanical behavior, the mechanism is simulated alone, as a system.
- You can plot on demand using the Signal Monitor user interface. See Analyzing Virtual Execution Results.
- You can display internal signals of the mechanism using the Signal Monitor. See Analyzing Virtual Execution Results.
- You can see the 3D Digital mockup animated to follow the computed behavior. (The diagram view is presently empty. The 3D position command is presently working with the logical 3D component, but not with the physical component.)
- You can detect and handle clashes.
Usage in the Design Process
Depending on how the design process looks like, the following three scenarios are typical.
Adding a System Definition to a Physical Digital Mock-Up
In this "Mechanical CAD" centric process, you add a logical system definition to a physical digital mock-up, to control and actuate the mechanism.
Top-Down Design; Relating System Architecture to Mechanical Design
In this top-down approach, the designer creates a dedicated logical component to collect the signals that are to be exchanged later with the physical product. This logical component can be seen as the interface between the system and its mechanical sub-system. This component is then connected to the rest of the logical architecture. You can define a number of alternative behaviors to this component to be able to do early simulations.
Later, the logical system and the physical model that has been developed in parallel are put in relation; the user is now able to set up the final model taking into account the Logical and Physical parts. This model can also be simulated.
Note that this is the reversed strategy of the "Mechanical CAD" centric process, by creating a component that fits the logical reference generated automatically afterward; and then create and connect to that component.
Early Validation of System Composition
Controlled kinematics is supported; the controller directly drives the position of the mechanism, i.e. the actuators are providing infinite energy. Kinematic behavior of the mechanism is considered, and constraints are handled. This is useful for early validation of system composition.