arbitary function

[Chielmi]

Hello, I’m a mechanical engineering student from the Netherlands (TH Rijswijk) and for a project I am developing a steam engine test setup. I am designing a program in Lab view to make a power and torque curve. I want to simulate before I connect the sensors to the computer. I already fount the arbitrary function and I think I can use to simulate a steam engine. By sample I simulate the RPM signal by defining the signal (with different accelerations like 0-100 (y-ax) rpm in 1(x-ax) second and 100-800 (y-ax) rpm in 2(x-ax) When I run the program it only shows the last value of the signal defined by me.  Can anyone help me so the program will show al defined values, in the gauges and the graph. Greets,

[jyang72211]

Hi,

It would be easier if you post the code, but let me take a stab at it.  If you are generating the data in a loop, and you don't enable indexing at the outer boundary of the loop, you will only get the last point that you generate. 

[Chielmi]

Thanks for your reaction, below a print screen of my defined signal.

 

[Dennis_Knutson]

A gauge cannot show all of the values unless you make multiple needles and I don't believe you could wire up dynamic data to it. You would have to build a cluster of scalars. Using a guage to display an array of values does not seem appropriate at all.

Your image does not show how you are creating the y input of the XY graph nor do I understand at all why you have your simulated signal wired to the x input. I don't even understand why you are using an XY graph in the first place. Just wire a normal graph to the output of the simulated signal function.

Also, clean up your wiring. It looks like you have wires going backwards (right to left) and that is not the standard convention.

Post an actual VI instead of a mostly obscurred image if you need more help.

[Chielmi]

Sorry for the messy drawing, here is a new one.

 

I thought that the gauge could visualize the signal of the sensor. For example the force that the load cell measures while the steam engine is running. The same kind as a temperature meter which also  showing different heights

The first signal I use is the signal of a load cell which measures force. With this force and some constraints I can calculated the torque. In order to make a torque curve (this is the goal of my test, it's the character of the steam engine) I need the RPM on the X-ax. There for I use a XY graph, 2 sensors one for the torque (Y) and  one for the RPM (X).

The second graph is for the power output, this is also a calculation with some constraints and is connected the same way on the XY graph like the Torque curve.

Thank you for your time so far, it's a learning process but I think it's gone work!

[Dennis_Knutson]

It's not a drawing, it's a block diagram and still messy. Looking at it, it appears you have no output from one of the multiply functions, you don't have the wire coming out of the right side of your second arbitrary function (it's on the left and underneath), the torque curve indicator is on the wrong side, etc.

As I said, if you want an explanation of something you are seeing or not seeing in one of the graphs, you have to post the actual code. No one has any idea of how you have configured any of the express functions. 

You are also dead wrong about how a temperature meter would respond. It would be just as silly to use one of these as it would be to use a gauge. These are scalar indicators and not suitable for an array. Only if you created the waveform one point at a time could you use a numeric indicator such as a gauge.