08-11-2019 01:30 PM
Hello-
I am currently working on a project where I am collecting data from 8 position sensors on a rotating shaft. The position sensors are paired together and each sensor in the pair, is positioned 90 degrees from each. The pair can be plotted in X-Y to display the shaft orbit.
I would like to be able to show all 4 orbits together on a 3D plot, but honestly I have never used 3D plots in Labview so I am a little unsure of how to go about this. Ideally I would end up with something that looked like the attached picture. The line connecting the bearing would be great but I'll consider it a nice to have at this time. There are 4 pairs of sensors.
So in summary what I want to do:
1.Plot 4 orbits along an axis with each orbit being further down the axis
2. Have a line connecting the most recent data point to the most recent data point in the other orbits "down the line"
I am mostly interested if you guys think this is possible and what direction would be best for me to start in.
Trent
08-11-2019 03:42 PM
Ok
After doing some searching it looks like the first part might be pretty easy. I am a little confused on how to get multiple channels. I am looking at the help file for the 3D Line Plot Setup VI (LV 2015) and it looks like there is something called "plots in" with something called obj. I guess I need a crash course in this now . . .I am going to keep hunting.
08-12-2019 07:38 AM
I am officially stuck! I have searched for a while but just can't seem to find an example that helps me understand how to get multiple plots onto a 3d Line graph. Does anyone have any examples of how to use the "plots in" obj to make 3 line graphs that are essentially spaced out as shown in the first post? this seems like it should be simple but I have not done much with objects before
Please help!
08-12-2019 08:17 AM
Can you share what you have tried so far, even if its a non running VI but contains some sample data, so people can have a look / play,
08-12-2019 09:28 AM
@obsessed wrote:
I am officially stuck! I have searched for a while but just can't seem to find an example that helps me understand how to get multiple plots onto a 3d Line graph. Does anyone have any examples of how to use the "plots in" obj to make 3 line graphs that are essentially spaced out as shown in the first post? this seems like it should be simple but I have not done much with objects before
Please help!
The create plot line.vi does not require a graph input, it will create an empty object. Simply add the VI 3 times with the x,y,z coordinate arrays.
Alternatively there is an ActiveX version in the Classic palette.
08-12-2019 12:54 PM
Fantastic. That worked like a champ.
Now on to Phase two. How do I connect one moment in time on the graph plotted on the 0 X plane to the same moment in time on the orbit plotted at the .5 X plane. basically I am trying to wrap my head around how to create the red line in the original picture.
As I think about it some more I am also not sure how useful it will be since I imagine the lines would look like they are stacking on each other and kinda fill in the entire graph. . .
Hmm
Any thoughts? I was trying to use this concept to see the phasing between the signals and maybe elude to the way in which the rotor is bending. . .
08-12-2019 01:58 PM
So the line that runs along the X-axis is connecting points with the same index number (time) between the 3 sets? It looks to me like a Bezier curve with only 5 fixed points, beginning and end (Y=0,Z=0 ?) and the 3 intersections with the data sets.
Since I don't want to do your work for you I will tell you how I would approach it. I don't think 3D graph does interpolation so you will have to that yourself if you want to make it as fancy.
You could create an array with interpolation points for the X-axis and make 2 Spline interpolations (e.g. https://zone.ni.com/reference/en-XX/help/371361R-01/gmath/interpolate_1d/), one for X-Y and the other for X-Z.