I am learning about how to use the expandable connector in dymola.
I am wondering how to ensure the compatibility between two control buses. My guess is that if I define an input variable called X in one control bus, then in the other one, I need to define an output variable also called X. So that when connecting these two control buses, they are coherent.
Based on the above idea, I define the two expandable connectors which represent the control buses, here is the screenshot.
Here is the setting I used when testing my ideas.
But when translating the model, I got an error message like the following. It seems I got the logic wrong. My question is that how should I use the expandable connectors so that they are coherent.
The underlying problem is that there are two public expandable connectors (buses) at the top of the model; and both could in theory be connected from the outside.
The best option would be to not have two public buses at the top of model, e.g.:
Remove one of the two buses
Make one of the two buses protected
(Or more complicated hierarchical variants.)
The VehicleInterfaces library does this in a good way (alternatively you can look some of the commercial libraries).
However, simplest way of making this work is to not declare anything in the buses, i.e. remove the declaration of both 'x' variables.
Related
I have some Modelica components that need to be connected twice, with two different connectors (lets call them typeAconnector and typeBconnector). Is there a way to build a "super-connector" that internally uses the two connectors?
The goal would be to have
connect(component1.superconnector, component2.superconnector
automatically translated into
connect(component1.typeAconnector, component2.typeAconnector);
connect(component1.typeBconnector, component2.typeBconnector);
Ideally, it should still be possible to do connect(component3.typeAconnector, component2.superconnector); and only the typeA subconnector part will be used.
I assume this is not possible, at least I have no idea where to start, any hints or workarounds or partial solutions welcome. Thanks.
Let's say I have a collaboration diagram that models a process named CheckMessage which is quite complex and spans over few lanes and pools. Now I would like to model another process, e.g. CreateMessage which would make use of the previous process to check first if message doesn't exist already or if all its fields are valid, etc.
The thing is, that both processes make use of the same swimlanes and pools. What is the proper way to model such interactions? I was thinking to model CheckMessage as a sub-process of CreateMessage, however sub-processes can't be attached to pools or lanes - if I understand it correctly they just stay within a lane of activity which invoked them. Can a Call Activity encapsulate such beahviour (cross pools and lanes)? Or can I somehow reference the CheckMessage diagram as a whole?
Thanks in advance.
I could think of the following approaches:
Using Diagram Reference: This is used quite often when you want to switch easily to the more complex part. The disadvantage is that, unlike Fragments in SDs, you do not have ways to really connect flows in and out of referenced diagrams.
Repeating parts of the process: here you just pick those actions from the complex process which ought to interact with the other process. You can highlight that by putting a boundary around these and adding a diagram reference as described above.
Call Activity: This is another valid way. Here you have an activity which you instantiate as action. The advantage here is that you can add pins for input and output parameters.
I guess there is no silver bullet and you have to choose what is appropriate in each case.
Edit Regarding #3 it looks like that:
(this is an example and not to be used in practice)
The Action to the right is an instance of the Activity as you can see by Ctrl-L (show parent).
Hi I am investigating OPC UA for my organization. I am trying to work out an example for a presentation based on an information or data example.
I have one for a on demand read operation and one for a continuous monitor. What I don't quite understand since I am just learning and haven't picked a vendor yet (lean towards United Auto) is how is the data represented?
For example if I have a data struct or object called machineInfo with 13 attributes (data) how would I create that on the server side and show how its done?
How would it fit in the BaseNode, Variable hierarchy? Or am I way off?
I can show high level or just code.
Thanks
MachineInfo would be an Object node (NodeClass of Object), with HasComponent references to each of the 13 attributes, which themselves would be Variable nodes (NodeClass of Variable).
As far as type definitions go, you could start out with just using the BaseObjectType and BaseDataVariableTypes, but if you're going to be using a client capable of taking advantage of more complex types you could create a custom ObjectType for the object. The variable components could be further exposed as AnalogItemType or DiscreteItemType, if applicable...
What programming language/SDK are you leaning towards?
Short version
I am considering to use BusObjects to implement hard interface control on a (large industrial) application using Simulink and I would like to store the BusObjects (hundrends of them) into a Matlab structure so that the entire application interface specification is well organized. However, it seems that BusObjects cant be contained into structures, nor they can reside on other workspaces other than Matlab Base. Any idea on how to handle this?
Long version
I would like the interfaces specification to be hierarchical and centralized in some way. I mean, I would like to specify the external interface of my application, then the internal interfaces, then the internal interfaces of the internal interfaces and so on. And I would like this information to be stored in one object that resembles the hierarchy. I was thinking in using an structure with BusObjects as elements.
Unfortunately, it seems that, for a bus object to work, it must be declared on the Matlab workspace as an independent variable of class BusObject. It cant be an element of an structure that is a BusObject, or an element of a cell whose elements are BusObjects or an element of a BusObject vector.
Any suggestion on how to handle this? take into account that if you have a model with dozens and dozens of blocks and more than 3 hierarchy levels, then you end up with hundreds of bus objects in the Matlab workspace without any particular structure... I think that is too messy to let it be...
Bus objects are always stored in the global workspace.
Send a request to Mathworks if you want to change this.
The user in this webinar;
http://www.mathworks.com.au/videos/parameterizing-bodies-68850.html?form_seq=conf1134
can create new levels of links for the scissor lift by copy pasting the sub systems.
I was wondering if there was any way the number of subsystems and the joints could be automated via user input.
i.e a gui which allows the user to input the number of levels in the scissor lift and that number of levels (subsystems) is generated in SimMechanics.
If someone could provide a solution I could adapt it to the problem I'm trying to solve.
Thanks in advance!
Yes, you can automate it, as long as you know what susbsytems and what joints you want to add. The functions of interest are:
add_block(path_to_your_subsystem,path_to_destination_subsystem) (I assume your susbsystem is stored in a library). You probably want to specify the 'Position` parameter so that all blocks don't end up on top of each other. It will take some experimenting to find coordinates that work for your model and that are parameterised based on the number of susbystems to add.
add_line(path_to_subsystem_of_interest,path_to_output_port,path_to_input_port). You'll need to know which port you want to connect to which and figure out how many times you need to do this based on the number of subsystems to add. Simscape and SimMechanics are a special type of ports, and you need to refer to them correctly otherwise it won't work, see Programatically connect two subsystems for more details (note: this is undocumented as far as I know and is therefore likely to change in a future release).
So in short, yes it's possible (I've done it in the past), but it's by no means easy. See this blog for a very simple introduction.