Angle Calibration Problem: Digital Encoder

koolitude

I've been trying to do the Angle Calibration for my digital encoders. I've done several times already but the data obtained is too inconsistent. So, I didnt get any Calibration Constants for the Angle Calibration.

I've tried several times with different visual contrasts as well. But it didnt help. The result is shown below:


What's wrong?

By the way, could anybody explain how one can interpret the data obtained from the calibration process? What are those numbers representing?

DATA @0, 7,10,12,14,15,17,20,22
DATA     25,27,30,34,37,42,49,69
DATA     7,10,11,13,15,17,19,22
DATA     24,27,30,34,37,42,48,59
DATA     4,6,9,11,12,14,17,19
DATA     21,24,27,31,35,41,51,77
DATA     9,11,13,15,17,19,22,25
DATA     27,30,33,37,41,47,54,72

Autocorrelation data for Calibrate_All.exe:

281,270,281,345,350,399,384,458
425,448,417,425,402,438,394,353
366,336,307,318,332,278,276,318
273,307,286,278,319,278,306,271
299,277,255,285,230,221,241,210
182,167,177,182,170,154,141,116
110,106,105,122,102,108,99,94
103,101,96,102,126,130,115,136
122,132,160,169,154,170,220,210
271,299,289,345,371,382,402,403
417,428,467,404,434,377,407,375
377,313,333,291,311,317,277,315
276,292,307,272,307,294,272,310
293,270,247,242,224,205,213,188
180,174,186,164,136,153,148,118
136,126,114,118,99,95,112,93
96,100,96,103,101,121,108,127
141,126,152,142,158,176,228,212
255,296,321,311,385,395,448,451
417,422,411,438,437,400,412,392
325,317,346,296,280,286,271,312
268,278,311,293,271,268,304,265
269,270,271,262,254,237,197,214
184,179,186,169,160,144,144,131
109,127,113,120,102,118,103,92
109,111,116,117,102,105,120,112
138,140,137,173,195,213,203,215
258,303,294,315,383,429,448,461
432,412,437,415,437,375,400,340
364,335,293,303,274,273,312,279
274,271,296,314,275,280,309,289
258,244,254,253,214,196,194,181

Thank you very much!!!!

Post Edited (koolitude) : 3/8/2007 3:49:11 PM GMT

Phil Pilgrim (PhiPi)

The message you received about inconsistent data occurs when the maximum autocorrelation value is less than 0.975. I know this sounds like a awfully high bar, and that your data looks very regular. Based on the graph, though, you're really close. I'd say just try it again, and make sure nothing changes while the 'bot is spinning around. This means that if you're in the photoresistor's field of view, you have to stand stock still until it's finished. If anything moves or changes, including lighting or objects in the room, the results will be inconsistent, and you'll have to try it again.

Good luck! You've almost got it!

-Phil

koolitude

Thank you very much Phil!
I finally got a consistent result after trying again and again and again... haha...

lifeform

Hi, I've attempted many times to do the calibration.
Do my readings seem ok?
Or what is the issue?
Anyone have similar graphs?