phidgets

[dstafford]

What i am trying to do, is use the phidgets usb servo and usb analog interface in labview. It is nice cause they have drivers for labview. It works pretty well, i am driving the servo via the sin function, but i am also reading in the servo position via a potentiometer. What i want to do is to be able to over lay the sine function along with the potentiometer input, so when i put a load on it i can see how the resulting input (sin) varies from the out put (potentiometer). Something like putting twp signals and overlaying then in an oscilloscope. I attached the vi, but it wont fully work unless you down load the drivers from the phodgets website, but the signal outputs that im trying to mesh is there. Any help would be greatly appreciated.

David

[Brian_T]

dstafford,

Each time your while loop executes, you are merging a waveform of 100 data points with a single integer.  You need to merge the signals point-by-point so that they will correspond to the same time intervals.  Hope this helps!

Brian T
Applications Engineer

[dstafford]

Yeah i see what you mean, but how do i do it with my program?

[Brian_T]

I attached a simple example illustrating how you could achieve this.  You probably want to make the frequency in the Simulate Signal VI the same as the frequency that you are reading from the servo (i.e. while loop rate).  Try something like this and see if it helps. 

Brian T
Applications Engineer

[nitishkati]

Hi,

I'm trying to use Phidgets with LabVIEW.

Looks like you guys have made some progress, but I can't open the attachments you have posted because I use LV8.2. Can you save your programs in LV8.2 and post them for me ?

I have been to the Phidgets site and have downloaded the stuff they have there.

But I don't know how to get them going (they show errors when I open them in LV).

May be this is a stupid question, but all help will be appreciated !!

Thanks,

Nitish

[dstafford]

I can provide some insight. Are you trying to use the servo contoller or just read data in from sensors? and yeah the example files did contain some erroer, i had a few when i tried to use it the first time.

David

[nitishkati]

Hi David,

I am working on building a flight simulator, so (eventually) I will be writing positioning logic (control a DC motor to position an axis based on pos feedback from a pot ). I will also be using digital IO control (for switches and lamps).

I am quite familiar with LabVIEW itself when used with NI cards (IO control, DAQ, Encoder Feedback etc), but I am not a Windows / C++ / .... programmer. Am a little lost when it comes to 'Event' based programming.

There seems to be some ' IPhidgetsInterfaceKit ' which probably has to be downloaded and used as an NI Library.

Do you know (a) where to get that from and (b) how to get it going ?

Nitish

[dstafford]

http://www.phidgets.com/downloads.php?os_id=1

There is the link for the drivers, if you scroll down you will see downloads for labview. This is of course provided that you have a basic interface hardware kit, the 8/8/8 comes to mind.

David

[nikhilvastarey]

Hello David

Could you please elaborate on the 8/8/8? and what did you mean by the interface kit?

I, too, am planning to buy the phidgetmotor controller HC to control a DC motor pump. 

The LV (labview) prog provid in the website : am i to understand that, the prog can control the speed of the DC motor? Is that what the program is doing?

One more query:

I must ensure the voltage of the pump does not fall below 4V. If that happens, then the motor will stall that will lead it to go bust ( the motor ie)

Is there anyway to ensure that through software (ie thru LV prog that has been provided in the phidgets website?)

I know that the PWM alters the power supplied to the motor, not the voltage. But I hope you can understand what i am saying.

@all

So, if I buy the phidget motor, connect the USB to the PC, open the LV example prog that has been provided in the phidgets website, will the program and the hardware run smoothly? ie, should I do any extra coding??

Nikhil

Many more Kudos to give:) 

[dstafford]

Is this the motor control that you want to use?

http://www.phidgets.com/products.php?category=6&product_id=1064

This is the only DC motor controller that I see, the rest are for stepper or servos. There is a motor controller example in the labview examples on the phidgets website,  but I don't know how accurate it is or if it is made for this one unit. I wouldn't expect any thing to be plug and play you will have to add your own labview code at some point.

The 8/8/8 unit is a simple interface unit for analoge sensors.

http://www.phidgets.com/products.php?category=1&product_id=1018

If measuring the voltage is highly critical then you will need to add a voltage sensor to your dc motor voltage input. Something like this.

http://www.phidgets.com/products.php?category=2&product_id=1117

But you will need an interface board to attach to that sensor. So then you will need to add some sort of logic to the labview code to always watch the voltage of the motor and then tell it what to do in the event of a power failure.

I hope this answers your question

David