NI Home > Community > NI Discussion Forums

Measure

Showing results for 
Search instead for 
Do you mean 
Reply
Member
053647967
Posts: 8
0 Kudos

speed measure with DAQ and torque transducer

Can anyone tell me how to convert the voltage i get from torque transducer, which can measure torque and velocity eather. I made a program with labview, but it gives me some voltage. I'd like program converts me that voltage to a velocity. 

Thanks for answers.

Member
e2m0i0l7
Posts: 124
0 Kudos

Re: speed measure with DAQ and torque transducer

Hi, 

 

Could you please attach a link to the sensor you're using?

 

Regarding torque measurements, you could find the following webcast very useful: 

http://zone.ni.com/wv/app/doc/p/id/wv-2124

 

What Hardware and Software are you using?

 

Regards, 

Mircea

Member
053647967
Posts: 8
0 Kudos

Re: speed measure with DAQ and torque transducer

http://www.eth-messtechnik.de/pdf/DRFL-I-VIII.pdf

we use DFRL - II- 10-n

 

Thank you very much for helping me.

 

Best regards, Simon

Member
e2m0i0l7
Posts: 124
0 Kudos

Re: speed measure with DAQ and torque transducer

Hi Simon, 

 

As far as I see, the sensor you are using provides information about torque, angle and speed, and needs a 12V excitation voltage.

 

You could see it as having 2 different sensors (speed (digital signal) and torque (analog signal)) and treat them as such, by connecting the corresponding lines to corresponding measurement devices.

 

Now, the next step is to make sure you have the proper NI Hardware and Software to acquire and analyze the signals provided by the sensor.

 

Could you please tell us what HW and SW are you using?

 

Also, It would be very useful for you to contact the NI Branch from your country to configure and acquire a measurement system. If you tell me your country, I could help you with that.

 

Mircea

 

Member
053647967
Posts: 8
0 Kudos

Re: speed measure with DAQ and torque transducer

I use NI USB 6212 with driver we got with it. For data aquisition in use labVIEW 8.5. 

So I should connect speed signal I get from torque transducer to a digital input? So that must be the problem. I connected it on analog input. 

I'm from country Slovenia. I can contact NI branch from our country if it still wouldn't work after I try with the digital input.

 

Thank you for help. 

 

Regards

Member
e2m0i0l7
Posts: 124

Re: speed measure with DAQ and torque transducer

First of all, we need to deeply understand the signals we receive from the sensor.In my opinion, the information from the datasheet is not the most comprehensive :smileyhappy:

 

Sensor requires  12V DC, 160mA excitation.

Torque: 0V-10V, -10V-0V  depending on direction - should be connected to AI

Speed 60 pulses/rev - should be connected to counter 0

Angle 360 pulses/rev (two signals- angular encoder) - should be connected to counter 1

 

What I would recommend is you started with LV examples for:

Hardware Input and Output -> DAQmx 

 

Torque - Analog measurements  and then scale the signal to result in strains   

Speed - Counter Measurements -> Digital Frequency

Angle  - Counter Measurements -> Position

 

Please find the proper example, scale them properly, make each work individually and in the end, integrate the three examples into one single application,

Mircea

Member
kkpraksa
Posts: 7
0 Kudos

Re: speed measure with DAQ and torque transducer

Hello

 

I made a VI program, which drives me a motor by giving voltage which I put on regulator who drives a motor. In first loop it starts motor with a ramp in second loop it holds 10 volts, in 3rd loop it stops the motor with a ramp. With the same program I measure torque and speed. I made each work individually and in the end, I integrated the three examples into one single application as you suggested. But now the program doesn't work and I can't find the problem. So I attach a VI and if you can quickly look at it and tell me what's wrong, it would be great.

 

Thank you.

Member
e2m0i0l7
Posts: 124
0 Kudos

Re: speed measure with DAQ and torque transducer

Hi,

 

This is not really the best architecture, it would be easier to use only one piece of code that is writing a trapezoidal signal (instead of 3 codes writing a part of the whole signal).

 

Could you please attach each of the individual elements in the code that are working?

 

Mircea

Member
kkpraksa
Posts: 7
0 Kudos

Re: speed measure with DAQ and torque transducer

ok that vi was not good i agree. i created one which measures me a speed and one which runs me a motor, with that trapezoidal signal. But i don't know, how to get that trapezoidal signal other way. can you tell me that, please? I'm brand new at labVIEW and I'll probably use it only for that task, so I don't know a lot of functions it has. I almost finished this task, so if you just tell me about that trapezoidal signal it would be great.

 

Thanks. Regards

 

Simon

Member
e2m0i0l7
Posts: 124
0 Kudos

Re: speed measure with DAQ and torque transducer

Hi Simon.

 

I have attached a subvi that generates a trapezoidal signal, you can set rising, steady state and falling durations in samples.

 

You can also set the starting and steady state values.

 

Use it in your application for AO to create the signal for controlling the motor.

 

In parralel loop to the generation, use your counters to measure speed, torque

 

Mircea