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3D coordinates of point on surface

I have a data series describing the characterisation of an induction motor, wherein there are 2 independent variables, Input Current and Rotor Speed, and one dependent variable, Output Torque. During the data collection process, multiple constant current series were collected (from 1-9A in 1A inc.s) during each of which the rotor speed was increased in steps of 20 (from 0-240RPM). At each instance the resulting torque generated by the motor was recorded.

What I now need to do is interpolate within the resulting 3D surface described by the collected data to allow me to determine the output torque for arbitrary current inputs and rotor speeds. For example, if I have an input current of 3.2A and a rotor speed of 123RPM I would like to know what the resulting torque generated would be based upon interpolation between recorded values.

I've been able to plot this surface on a 3D surface chart, and from this I can see visually what I need to do but I can't get my head around the problem mathematically! Any advice would be much appreciated, test VI attached.

OG
Research Engineer



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Check altenbach's bilinear interpolation examples here:

http://forums.ni.com/t5/LabVIEW-Idea-Exchange/Interpolate-array-for-higher-dimensions-bilinear-trili...

 

If idea helps, kudo it

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Thanks for the link, however I'm stil not clear how to implement this with my data. Essentially what I have is a series of 2 dimensional lines plotted at intervals on a third dimension, as opposed to three indepedent axes with data scattered amongst these. I hope that make some sort of sense!

OG
Research Engineer



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I've managed to achieve what I need using the 2D Interpolation VI as attached. Thanks for the help.

OG
Research Engineer



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