Labview to build moving graphical components

[Siniz]

Hi,

I am trying to decide upon a frontend graphical interface for a project. I want to see if you guys can tell me if Labview can handle this easily.

I have this OPC server where I get X and Y coordinates of an AGV. What I want to do is to fetch these variables as soon as they update, or at a specified interval, and then move a block/image (a block or image representing an AGV) to new coordinates on the screen. So basically it would be like a live updated view of where on an area the vehicle is located. All the variables will be fetched from an OPC.

Is this possible and easy to accomplish with Labview? Which component of labview should be used to fetch OPC data and which component should be used to represent a graphical block/image that moves and updates it's position from the fetched data? What it comes down to is if the company should spend the money on this program or not. If this is doable without too much hazzle, Labview seems like a good candidate as a new program in our arsenal.

Thanks

[tst]

LabVIEW is not the most appropriate tool when it comes to dynamic graphics, but if you only want to display (not to control), this can be done relatively easy with the picture control. Here are some example of working with it.

Another option, if you know a maximum number in advance, is to use property nodes to determine the position of controls on screen.

OPC can be done with LabVIEW using the Datasocket primitives. You should be able to find some examples by searching the example finder (Help>>Find Examples) for "OPC".

Do you have any experience with LabVIEW? What are the other options you are considering?

[Siniz]

Hi and thanks for the reply,

I do not have any experience with LabVIEW. I am trying to find a software for a project that can update dynamical blocks (they should represent vehicles) and I heard LabVIEW could do this.

Controlling the vehicles is not that important, but it would be a nice feature if it was possible.

The other software I am thinking of, which also seems to actually be able to handle this with ease, is Wonderware InTouch. I haven't got any experience with either software. I would have to learn as this project goes along.

Any more input on this topic would be of great help and I appreciate every reply.

Thanks

[tbob]

Wonderware is one of the top choices in the SCADA world.  (Supervisory Control And Data Aquisition).  It has some graphic figures ready to use, such as control valves, tanks, switches, pipes, etc.  You can control these graphics to make them visible/hidden, blink, change color and others dependent on data points being aquired or buttons being pushed on a front panel.  Normally, InTouch is used with PLCs (Programmable Logic Controllers).  It communicates with the PLCs through built in protocols (such as Modbus) to get data from endpoint devices (switches, transducers, etc) which are connected to the PLC.

Labview can do the same thing, but you would have to search for the pre-made graphics, or use some drawing tool to draw your own.  To move the graphical object, Labview could easily do this by using property nodes to set the graphic position on the front panel.  I'm not sure if InTouch allows you to move graphics by specifying their front panel position programmatically.  I used Wonderware for 3 years and never came across a situation where I needed to do this.

I guess it depends on what your hardware is like.  How are you gathering the data.  Using PLCs?  4 to 20mA transducers?  Give us more info.

[Ben]

I have had a number of customers that know and use Wonderware. From what I understand, if you can do what you want using Wonderware then use Wonderware.

If what you want can't be done with Wonderware, then LabVIEW can be used to implement what can't be done with Wonderware.

Ben

[tst]

You should also note that LabVIEW is not a SCADA tool - it is a programming environment, so you have to code anything you want to do. Coding in LabVIEW is significantly easier than in C or JAVA, but it's still a point to consider. There should be a fully functional evaluation version available on NI's site.

[Siniz]

Great replies!

I am not actually sure how the actual data is beeing gathered as of right now, as that is not my part of the project. I just got involved in this and I am searching for a professional solution to display dymanic graphical data. It does not really matter how the data is beeing gathered. What is of importance is that it will be available on an OPC server (I also know that the variables will be available through a C++ environment). I can thus fetch the variables directly from the OPC server, or possibly from the C++ program beeing coded.

What I want to achieve is really quite simple in theory. I got vehicles that moves continously and the position of the vehicles are stored on an OPC server. Let's say they are updated every 100ms. The vehicles move in a set field. Let's say a baseball field. I want to draw that baseball field as a static entity in the frontend program. I then want to draw the vehicles on this baseball field. The position of the vehicles should be updated every 100ms.

That's all. No control is needed (as step one anyway). I don't need to make sure the cars collide or antying, it's all handled by other software. I just get coordinates and want to display the vehicles at these coordinates.
I was pointed to either Wonderware or LabVIEW. Maybe there are other even easier programs that can do this. I don't know. Right now I'm in the research stage of the process and so far you guys have been of great help. It's starting to get more and more clear. Any more input is of course welcome, especially if you can point me to something that would do exactly what I want to achieve. Be that in LabVIEW or Wonderware!

/Tobias aka Siniz

[tbob]

This would be easy to do using Labview.  I wrote a small and simple example to show how the objects property node for position can be used to move the object.  Run the vi, increment or decrement the Position control.  The "car" will move horizontally and vertically everytime the position is changed.

You can download a trial version of Labview from the NI website (ni.com) if you don't already have it.

Message Edited by tbob on 01-07-2008 03:22 PM

[Siniz]

I tried to find a trial version on the website but had no success in finding it. Could someone point me to the right direction?

[KostasB]

Hi,

Click on

'LabVIEW 8.5 Evaluation Software Download' at:

http://digital.ni.com/demo.nsf/display?ReadForm&lookup=Evaluation%20Software&view=type&node=157200_US 

If you are talking to OPC servers , the LabVIEW DSC (Datalogging and Supervisory Control module)

is the ideal National Instruments solution.

https://www.ni.com/en-us/shop/product/labview-datalogging-and-supervisory-control-module.html

Please let us know how you get on.

KostasB

National Instruments

Applications Engineering