Interface needed to measure multiple sensors

[nmoh7]

Hi,

I am really new at using Labview Real Time. My project involves designing a magnetic levitation device in 3-D. I don't really understand how to implement it with Labview Realtime, i.e how to i control my project with my computer and what interface can be used to actually get the data's needed. Please help!

I have trouble imagining the whole setup basically.

Thank You

[NIJanell]

Hello nmoh7,

Do you have any additional details on the project?  It seems that getting you started should be fairly easy, but I'm not really sure what you are trying to do.  So you have a magnetic levitation device - what exactly does that mean?  Do you need to control the device or only get data from it?  To control the device, what sort of information (or data points) do you need?  What kind of sensors do you have at your disposal?  If you can more thoroughly explain the set-up outside of the computer, I think I can help you get started on programming and system interface.

Here's some good tutorials for getting started in LVRT.

LabVIEW Real-Time Architecture and Good Programming Practices

Advanced LabVIEW Real-Time Development Resources and Benchmarks

List of RT tutorials on Developer Zone

Good luck!

Janell R | applications engineer

[nmoh7]

Do you have any additional details on the project?  It seems that getting you started should be fairly easy, but I'm not really sure what you are trying to do.  So you have a magnetic levitation device - what exactly does that mean?  Do you need to control the device or only get data from it?  To control the device, what sort of information (or data points) do you need?  What kind of sensors do you have at your disposal?  If you can more thoroughly explain the set-up outside of the computer, I think I can help you get started on programming and system interface.

Hi Janell,

Here are more details regarding my project.

Basically, I am going to build a magnetic levitation device which will levitate a stell/metallic ball. I will be using three coils as the electromagnets and this will be the lifting mechanism. I need to control the ball so that it is stabilize in mid air, and perform actions such as altering the current going through the three coils in order to make the ball move in a circle whilst being suspended in air. 

Thus, I need to control the device as well as get data from it. Data would probably be the voltage readings and maybe the position and velocity. I'm not particularly sure as yet. Sensors wise, I am thinking of using  infrared transducer or maybe ultrasonic transducer.

I will be using a desktop computer as the host . Lets say I have built the structure for my device right... From there, how do I connect the computer to the magnetic levitation device in order to perform the commands i need (i.e reduce current or change reference point etc).?

I hope I've explained the details of the project clearly.. Thanks a lot for your help.

[NIJanell]

Hello nmoh7,

When you say that you will be using a desktop computer as your host, do you mean that will be your development machine?  If you plan on doing this with LabVIEW RT (which I personally think is required), you will also need a target machine before interfacing with the levitation device.  The target machine will run a real-time operating system which encourages determinism in your system.  For the target, you can use a desktop ETS system, PXI controller, cRIO, or FieldPoint.  Check out potential targets here.

Now, your target will need both analog inputs and outputs to get data from the system and control it.  Once selecting a target platform, we can look at the different modules/cards needed to give you enough channels.

Good luck!

Janell

[cslai3]

Hi Janel,

It is me nmoh7 using a different username here.. 

With regards to the targets, we have a budget of $150 dollars. So, i guess that cancels out field point, and compact rio yeah? another question is, would the bandwidth be big enough to perform real time measurements if i use a desktop PC? what about PCI cards or Elvis? are they an option for me?

Thanks

[cslai3]

Also, my supervisor suggested using an FPGA. would that be hard to configure? knowing my no knowledge on labview itself

[NIJanell]

Hello cslai3,

If you are interested in using an FPGA, the cRIO would be a great place for you to start but there are some other FPGA hardware targets.

In general, a PCI card or ELVIS will not work, as you need a dedicated system running a real-time operating system.  This means that if you use a desktop PC, it will only have LabVIEW RT running on it - no Windows.

Here's a simple LabVIEW FPGA tutorial.

Good luck!

Janell R | applications engineer

[nmoh7]

Hi Janel,

Please do help me pick a target that best suites my project. As mentioned before, i have a budget of $150. I am not good at FPGA's, so if possible, i am trying to avoid having to use them. Can you suggest a target and any extra hardwares that i can use to start on my project please? It would be of great help if i can get this issue settled. Thank You so much.

[NIJanell]

Hello nmoh7,

As I'm sure you noticed by looking through the RT hardware that I linked before that there is nothing within your price range.  Is there any hardware or software that you already have?

Have a great weekend,

Janell R | applications engineer

[nmoh7]

Hi Janel,

yes the prices for FPGA are a lot more expensive than i thought We do have labview software installed in uni, and also the real time software if i'm not mistaken. hardware wise, we have elvis in the labs, but i'm not allowed to hang on to the prototype boards that connects to elvis nevertheless, my supervisor gave me a custom made board that can also be plugges into elvis. It only has about 5 ADC and 5 DAC bnc connetors port.Nothing else. What about using a desktop as my target. That would be ok too right? According to my supervisor, we might be able to get that et up but we'd have to get the A/D card that needs to be plugged into the desktop...

I actually need help in the programming bit also actually.  But i'll figure out everything about the algorithm properly before asking so i won't change my mind so much.

thanks