XPS controller-stages move continuously

[menglian]

Hi,

I have a Newport XPS C8-controller. It works well via webface GUI. Now I want to use labview to achieve the functions as below:

1. the stages can work continuously. eg. When it moved from a target position 1 to target position 2, the stages don't have to do home initialization and home search again. It moved directly to the target position.

2. How can I track the current positon of stages every 0.1 sec? In my VI, the current position only showed the final vaule.( its value close to the target position)

3. I have two stages. They are the same. Both of them are defiend as a single axis. How can I design the VI to make them move at the same time and have exactly the same motion? eg, track their position, record their position vs. time

4. I can change the speed of stages moving in webface GUI. How can I fullfill in labview. I didn't find any VI provided by Newport to set this parameters.

I didn't have too many experience of programming with labview. I already have taken NI labview course 1 and 2. Would you mind give me any suggestion or example VI to solve the proble mentioned above.

The VI I've already done so far is attached. 

[Emily-C]

Hi menglian,

The VIs you're using in your application are from a third-party device driver from Newport. I'd be happy to offer suggestions for your LabVIEW implementation, but unfortunately I think that all of your questions depend on the specific VIs Newport offers for controlling your device. Did the driver installation come with any examples to get you started?

This forum post has more users discussing using the Newport XPS Controller in LabVIEW. It's an old thread, so I don't think it's very likely you would get a response to a new post, but some of the tips they discuss might still be useful to you.

I'm sorry I can't answer more of your questions, it might be a good idea to contact Newport to find out more about the specific VIs available to you. 

Regards,

[menglian]

Hi Emily,

Thanks for your kind reply. Actually, I've already read other posts about Newport XPS controller in this forum before I post mine. And I've already obtained some example VI from Newport, which went along with the instrument. And my VI attached last post was based on the example VI/ SubVI provided by Newport. Maybe my questions in previous post are not very clear. Can I use some structures in labview to make a function work continuously? Such as while loop. But the problem is that I need to do some changes from one run to the next. Any example VI can I refer to from the labview library?

Thanks,

Menglian

[Emily-C]

Hi Menglian,

If you want to be able to go through a while loop, but do something different different times you run through, then I think you should try implementing a state machine.

As far as your specific questions, from what I understood they are more related to specific VIs.

1. The state machine would help with this. In an initialization step, you could do home initialization and search. After that, you could just go through a "move" step where you move from your current location.

If these are the only two options and you'll never need to go back to initialize, you might also be able to just have one while loop. Do your initialization before the while loop, then have the standard move (no initialization) in the while loop.

2. It looks like the VI you're using does the full move before it completes. If that's the only VI they have for moving, I'm not sure how you'd check position as it moved. Do you know if the VI you're using to check the distance can be used in parallel? You could use two parallel while loops, with the position check one running faster, to constantly update your position. But again, this relies on the ability of their VIs and if you can make both these calls at the same time.

3. If you want exactly the same time and motion, you probably want specific VIs that can accomplish this synchronization. You could use the same loops and settings to make approximately the same motion, but that won't be the same thing. Newport might have more information on these capabilities.

4. Setting the speed of the stages would need to be done by device driver VIs provided by Newport. They might have more information on this.

I hope that helps. I can help you with the overall structure of your application, but a lot of what you're trying to set up is dependant on the VIs available to you, which Newport should be able to help you with.

Thanks!

[menglian]

Hi Emily,

Thanks so much for your kindly reply. I think I have solved most of my problems based your solutions. Two stages can move together now with two parallel while loops. But it seems that the time difference still existed, less than 1 second. The revised VI is attached.

I still have a question about data saving or data polting. In my VI, I used the wave graph chart from labview. The value of Y axis came from instrument, which can be recorded now. The value of X axis was time. Can I change it to other parameters, such as the displacement of stgaes? I've already know the function between time and displacement.

Wish to hear from you.

Thanks,

Menglian

[Emily-C]

Hi Menglian,

Synchronization between the two motors is one of the things that I suggested will probably rely on specific VIs. Parallel loops is not true synchronization. Our NI-Motion drivers for our motion cards have specific VIs that allow you to move two motors synchronously. It's possible that Newport provides something similar.

If you want to plot against something other than time, you could use an XY Graph. You can read more about XY graphs under LabVIEW Help Types of Graphs and Charts.

Good luck!

[menglian]

Thanks. I will try that.