# Has anybody ever tried to measure the Earth rotation with ADIS16460?

I tried to check the possibilty of the Earth rotation rate measure. I cannibalized old HDD to prepare the rotating table, attached the device to the plate, and performed the series of recordings, turning the device by 180° every 75 seconds, after 10 rotations the results were calculated. 15 series of 10 rotations each were recorded.

Certainly i could catch only horizontal component (vertical is invisible due to linear acceleration effect), i.e. i need to multiply the value by the cos(55.75°). The latitude of my office is 55.75°.

Can you bet the average measured value and STDEV for 15 series of 10 rotations each?

Do you think this research worth writing an artice?

• Thank you for posting this. I am not sure that I understand what you are observing the earth’s rotation for.  With an in-run bias stability of 8 dph, I wonder if that could limit your resolution. Do you have any insight on this? Thanks again!

• Earth rotation rate is 15 dph, horizontal component at 55.75 latitude is 8.465 dph. Really, ±8.465 dph, depending upon positive or negative orientation. Many skeptically-minded engineers say that the stability is measured only during static (motionless) conditions and if the real rotation or movement will happen, the stability will degrade.

The basic purpose of this experiment was to prove the stability during rotation does not degrade and one can measure Earth rotation using this device. But, because the stability limit is about the same as the signal, one can't hope to get accurate value.

So, I ask you, how do you think, what was the average value of the 15 tests 10 rotations each? I used 2 units of ADIS16460 and some tests were conducted with X sensor and some tests with Y sensor.

• If someone is interested, i can attach Excel files with the results of this experiment.

•  Test no Sensor no Active axis Value measured Relative to actual 1 1 X ±0.002176°/s 0.924 2 1 X ±0.002727°/s 1.160 3 1 Y ±0.002235°/s 0.951 4 1 X ±0.002408°/s 1.024 5 1 Y ±0.002527°/s 1.075 6 1 Y ±0.003327°/s 1.415 7 1 Y ±0.002918°/s 1.241 8 1 X ±0.003391°/s 1.442 9 1 X ±0.002346°/s 0.998 10 2 Y ±0.002116°/s 0.900 11 2 X ±0.002533°/s 1.077 12 2 X ±0.002394°/s 1.018 13 2 Y ±0.002028°/s 0.862 14 2 X ±0.002095°/s 0.891 15 2 Y ±0.002287°/s 0.972 16 2 Y ±0.002189°/s 0.931 average average ±0.002481°/s 1.055 STDEV ±0.000403°/s

Actual value computed as 360°/86164*cos(55.75°)=0.002351°/s