Non linear analog input - measuring distance

[barkul]

Hi, what is the best way to implement analog input with non linear characteristic? I want to measure distance with Sharp GP2Y0A41SK0F sensor, then use this measurment to position leadscrew nut. I am using Automation Studio 4.12

[stephan.herbig]

Hello Bar,

in such a case, I use the “MTLookUpTable” function block to linearize the characteristic curve.

MTLookUpTable

Regards

Stephan

[christoph.hilchenbac (Christoph Hilchenbach)]

I think it could be necessary to limit the table to the red curve since the values below 3 cm are not clearly assignable:

[job.franken]

Depending how accurate the values in between the points need to be you could also use ‘polynomial fitting’ .

The sample uses the Gauss Elimination within a function which gets the same results if you put it in Excel.

PolynomialFitting.zip (136.4 KB)

[barkul]

Yeah that is true, producer says it measures 4-30 cm

[barkul]

If I can create my own arrays, I think it would be best solution, but I can’t find this function block unfortunately using AS 4.12.6.106

[eun.im]

Hello,
Please search without a filter. It’s under mapp control using AS4.12.8.41.

[barkul]

Maybe I need newer version of AS or student license is not including this function

[michael_w]

Hi there,

try installing it

Also please note that the AS license doesn’t remove functionality, so any time you don’t find something, it’s not your license. It might limit usage, but not hide a function from you:

[barkul]

Thank you, solution was very easy, but still didn’t think of it, thank you