Sharp IR Distance Sensor Algorithms

erco

I love me some Sharp IR distance sensors, even if their analog output is non-linear. I suspect most of us use these either with lookup tables or in non-precision applications where rough ranges are used. But this morning I found some hardcore equations at https://www.upgradeindustries.com/product/58/Sharp-10-80cm-Infrared-Distance-Sensor-(GP2Y0A21YK0F) and https://www.upgradeindustries.com/product/57/Sharp-20-150cm-Infrared-Distance-Sensor-(GP2Y0A02YK0F)

Depending on your ADC resolution and other factors, you might not need floating-point accuracy to 6-7 sig figs.

Publison

That's good stuff!

Thanks for sharing. Now....Bookmarked.

erco

There's an older Parallax PDF along these lines, using a Sharp sensor with an ADC0831. BS2 code within did an approximate curve fit, based on ranges. Perhaps not to 6 sigfigs though.

I bet Jim has that PDF and will post it. Or will I find it first?

erco

http://cdn.instructables.com/ORIG/FZF/AL36/F9T3ZZEN/FZFAL36F9T3ZZEN.pdf

Publison

Sorry, was sidetracked with my new DJI Phantom 3 calibration.

Have to see what the competition is doing.