Accelerometer to detect very small vibrations

Question

I am working on my own little project where I need to do detect CNC machine spindle vibrations. The spindle spinning up to 30000rpm and vibrations expected are less than 1mm. I have purchased lis3dh module and tried to run some Arduino program on it. It seems that the sensor output is very noise. When the sensor is standing still on my table, the readings are as following:

08:43:18.224 -> X: 491
08:43:18.224 -> Y:-15883
08:43:18.224 -> Z:-1230
08:43:18.224 -> X: 518
08:43:18.224 -> Y:-15862
08:43:18.224 -> Z:-1529
08:43:18.224 -> X: 302
08:43:18.224 -> Y:-15915
08:43:18.224 -> Z:-1260
08:43:18.224 -> X: 472
08:43:18.224 -> Y:-15948
08:43:18.224 -> Z:-1350
08:43:18.224 -> X: 435
08:43:18.224 -> Y:-15892
08:43:18.224 -> Z:-1243
08:43:18.224 -> X: 595
08:43:18.224 -> Y:-15840
08:43:18.224 -> Z:-1398
08:43:18.224 -> X: 406
08:43:18.224 -> Y:-15867
08:43:18.224 -> Z:-1158
08:43:18.224 -> X: 584
08:43:18.224 -> Y:-15857
08:43:18.224 -> Z:-1537
08:43:18.224 -> X: 291
08:43:18.224 -> Y:-15924
08:43:18.224 -> Z:-1452
08:43:18.224 -> X: 428
08:43:18.224 -> Y:-16041
08:43:18.224 -> Z:-1419
08:43:18.224 -> X: 446
08:43:18.224 -> Y:-15883
08:43:18.224 -> Z:-1569
08:43:18.224 -> X: 596
08:43:18.224 -> Y:-15905
08:43:18.224 -> Z:-1304
08:43:18.224 -> X: 430
08:43:18.224 -> Y:-15865
08:43:18.224 -> Z:-1372
08:43:18.224 -> X: 489
08:43:18.224 -> Y:-15796
08:43:18.224 -> Z:-1051
08:43:18.224 -> X: 612
08:43:18.224 -> Y:-15865
08:43:18.224 -> Z:-1232
08:43:18.271 -> X: 510
08:43:18.271 -> Y:-15832
08:43:18.271 -> Z:-1308
08:43:18.271 -> X: 502
08:43:18.271 -> Y:-15916
08:43:18.271 -> Z:-1436
08:43:18.271 -> X: 251
08:43:18.271 -> Y:-15939
08:43:18.271 -> Z:-1284
08:43:18.271 -> X: 462
08:43:18.271 -> Y:-15891
08:43:18.271 -> Z:-1667
08:43:18.271 -> X: 417
08:43:18.271 -> Y:-15830
08:43:18.271 -> Z:-1486
08:43:18.271 -> X: 492
08:43:18.271 -> Y:-15884
08:43:18.271 -> Z:-1497
08:43:18.271 -> X: 516
08:43:18.271 -> Y:-15784
08:43:18.271 -> Z:-936
08:43:18.271 -> X: 459
08:43:18.271 -> Y:-15963
08:43:18.271 -> Z:-1497
08:43:18.271 -> X: 444
08:43:18.271 -> Y:-15809
08:43:18.271 -> Z:-1270
08:43:18.271 -> X: 291
08:43:18.271 -> Y:-15916
08:43:18.271 -> Z:-1353
08:43:18.271 -> X: 425
08:43:18.271 -> Y:-15779
08:43:18.271 -> Z:-1254
08:43:18.271 -> X: 580
08:43:18.271 -> Y:-15820
08:43:18.271 -> Z:-1097
08:43:18.271 -> X: 499
08:43:18.271 -> Y:-15856
08:43:18.271 -> Z:-1091
08:43:18.271 -> X: 688
08:43:18.271 -> Y:-15772
08:43:18.271 -> Z:-1148
08:43:18.271 -> X: 451
08:43:18.271 -> Y:-15838
08:43:18.271 -> Z:-768
08:43:18.271 -> X: 536
08:43:18.271 -> Y:-15891
08:43:18.271 -> Z:-1377
08:43:18.271 -> X: 377
08:43:18.271 -> Y:-16028
08:43:18.271 -> Z:-1494
08:43:18.271 -> X: 620
08:43:18.271 -> Y:-15868
08:43:18.271 -> Z:-1376
08:43:18.271 -> X: 624
08:43:18.271 -> Y:-15984
08:43:18.271 -> Z:-1024
08:43:18.271 -> X: 563
08:43:18.318 -> Y:-15974
08:43:18.318 -> Z:-1179
08:43:18.318 -> X: 409
08:43:18.318 -> Y:-15931
08:43:18.318 -> Z:-1304
08:43:18.318 -> X: 630
08:43:18.318 -> Y:-15920
08:43:18.318 -> Z:-1356
08:43:18.318 -> X: 345
08:43:18.318 -> Y:-15905
08:43:18.318 -> Z:-1484
08:43:18.318 -> X: 566
08:43:18.318 -> Y:-15865
08:43:18.318 -> Z:-1264
08:43:18.318 -> X: 403
08:43:18.318 -> Y:-15835
08:43:18.318 -> Z:-1438
08:43:18.318 -> X: 473
08:43:18.318 -> Y:-15955
08:43:18.318 -> Z:-1248
08:43:18.318 -> X: 468
08:43:18.318 -> Y:-15825
08:43:18.318 -> Z:-1358
08:43:18.318 -> X: 582
08:43:18.318 -> Y:-15878
08:43:18.318 -> Z:-1345
08:43:18.318 -> X: 443
08:43:18.318 -> Y:-15808
08:43:18.318 -> Z:-985
08:43:18.318 -> X: 558
08:43:18.318 -> Y:-15830
08:43:18.318 -> Z:-1401
08:43:18.318 -> X: 457
08:43:18.318 -> Y:-15873
08:43:18.318 -> Z:-1036
08:43:18.318 -> X: 416
08:43:18.318 -> Y:-15956
08:43:18.318 -> Z:-1654
08:43:18.318 -> X: 419
08:43:18.318 -> Y:-15992
08:43:18.318 -> Z:-1128
08:43:18.318 -> X: 342
08:43:18.318 -> Y:-15907
08:43:18.318 -> Z:-1507
08:43:18.318 -> X: 377
08:43:18.318 -> Y:-15862
08:43:18.318 -> Z:-1174
08:43:18.318 -> X: 600
08:43:18.318 -> Y:-15881
08:43:18.318 -> Z:-1220
08:43:18.318 -> X: 574
08:43:18.318 -> Y:-15960
08:43:18.318 -> Z:-995
08:43:18.318 -> X: 467
08:43:18.318 -> Y:-15868
08:43:18.318 -> Z:-1414
08:43:18.318 -> X: 342
08:43:18.365 -> Y:-16054
08:43:18.365 -> Z:-1670
08:43:18.365 -> X: 457
08:43:18.365 -> Y:-15928
08:43:18.365 -> Z:-1644
08:43:18.365 -> X: 500
08:43:18.365 -> Y:-15974
08:43:18.365 -> Z:-1121
08:43:18.365 -> X: 502
08:43:18.365 -> Y:-15878
08:43:18.365 -> Z:-1174
08:43:18.365 -> X: 534
08:43:18.365 -> Y:-15785
08:43:18.365 -> Z:-1160
08:43:18.365 -> X: 560
08:43:18.365 -> Y:-15875
08:43:18.365 -> Z:-1064
08:43:18.365 -> X: 465
08:43:18.365 -> Y:-15936
08:43:18.365 -> Z:-1248
08:43:18.365 -> X: 643
08:43:18.365 -> Y:-15920
08:43:18.365 -> Z:-1155
08:43:18.365 -> X: 374
08:43:18.365 -> Y:-15929
08:43:18.365 -> Z:-1380
08:43:18.365 -> X: 614
08:43:18.365 -> Y:-15904
08:43:18.365 -> Z:-1481
08:43:18.365 -> X: 430
08:43:18.365 -> Y:-15926
08:43:18.365 -> Z:-1203
08:43:18.365 -> X: 492
08:43:18.365 -> Y:-15846
08:43:18.365 -> Z:-1177
08:43:18.365 -> X: 452
08:43:18.365 -> Y:-15830
08:43:18.365 -> Z:-1308
08:43:18.365 -> X: 641
08:43:18.365 -> Y:-15881
08:43:18.365 -> Z:-1081
08:43:18.365 -> X: 456
08:43:18.365 -> Y:-15889
08:43:18.365 -> Z:-1203
08:43:18.365 -> X: 444
08:43:18.365 -> Y:-15798
08:43:18.365 -> Z:-1187
08:43:18.365 -> X: 564
08:43:18.365 -> Y:-15892
08:43:18.365 -> Z:-1507
08:43:18.365 -> X: 363
08:43:18.365 -> Y:-15857
08:43:18.365 -> Z:-1292
08:43:18.365 -> X: 467
08:43:18.365 -> Y:-15808
08:43:18.365 -> Z:-1513
08:43:18.365 -> X: 358

As you can see from above, the readings fluctuate quite a bit therefore there is no way for me to tell whether thats a vibration or just random noise detected. Could someone give me any tips on how can this be achieved? I do not need very accurate results but at least something!

Why not filter for 500 Hz or a harmonic, to eliminate noise? For that matter, would direct pickup from coils placed near the shaft or other vibrating part work better than an accelerometer? — DrMoishe Pippik, Aug 20 '21 at 02:31
Please can you elaborate a little more. My hardware knowledge is close to nothing. — TheBestPlayer, Aug 20 '21 at 04:10
If the spindle rotates at 30,000 RPM, that's 500 revolutions per second, so likely the vibration is at that frequency, in which case an LC pass filter would emphasize that frequency, reducing signal outside it pass-band. On the other hand, if you're trying to pick up vibrations such as the bit chattering against work, you might want to block noise from the spindle rotation with a blocking filter. This is a bit too complex to explain from scratch, research L-C band pass filter. — DrMoishe Pippik, Aug 20 '21 at 16:58

Accelerometer to detect very small vibrations

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