3D printed Fiber Optic Gyroscope ( Sagnac Interferometer )

[@pile54000]

Nice job man , i have a suggestion : Why not putting voltmeter on a ball bearing so it will not spin with the rest of the devices so it can stay still so you can read the voltage while the rest spins?

[@plenum88]

Thanks - I have done that in later versions, but the best seems to be the wireless datalogger since then the data can be exported directly into Excel.

[@Resonant87]

congratulations! you've just detected gravity waves!! haha just kidding.. I like your setup and how sensitive that thing is. this for me tends to prove the drag theory of ether right. ever tried putting a gyroscope inside and spinning it up? just the gyro, keep the measuring device still.. or even a rotating magnetic field in a way that wouldn't influence the electronics?

[@kaptain113]

How does the phase control wheel work?

[@Astronomy_Live]

When aligned properly, is it sensitive enough to detect earth's rotation as you showed in the 1000 meter sagnac loop video, or is this one insufficient for that?

[@plenum88]

To do that the fiber should be quite a bit longer, perhaps 1000 meters or more. Increasing the radius along amplifies the sensitivity to rotation.

[@Astronomy_Live]

Alright, thanks for the info.

[@jamesbolivardigriz8252]

@@plenum88 does that have to be actual radius/circumference or can you loop 1000m several times and have nearly the same effective sensitivity modulo the effects of not being perfectly concentric?

[@plenum88]

@@jamesbolivardigriz8252 The effect increases with the area enclosed by the loop(s), so you can loop many times to increase the sensitivity. But it also increases with the tangential velocity of the loop, so for the same rotation rate, having a larger radius loop increases the effect as well. So bigger radius, more loops is best.

[@EnglishTurkishExpert]

I am sorry if this is a lame question: However if the device gives a voltage rise during rotation in both direction, how one may detect the direction? TIA

[@plenum88]

It is a good question - the best thing to do is to adjust the polarization paddle so that the returning waves are not in the anti-phase condition when the device is stationary (lowest voltage found by the paddle), but somewhere intermediate (between the lowest voltage and highest voltage found by adjusting the paddle), so that there is an apparent phase difference between them in the stationary state. When the device is then rotated, in one direction the returning waves will progress towards anti-phase, and in the opposite direction they will progress towards in phase, (drop in voltage, and rise in voltage, respectively). This is easiest to visualize at low rotation rates.

[@Pinkcybermonkey]

Dear plenum88, I was wondering what the cost for this project from scratch?

[@bilalabidbuttisking]

If we unroll a single loop of fiber from the wheel and move it slightly up,down,left,right (like it is vibrating), will voltmeter show any change?

[@plenum88]

Yes, bending the fiber will change the polarization state at the output, which will manifest as a voltage change. This is not a fringe shift, but it is hard to tell the two apart.

[@user-scienceislove]

is this experiment prove special relativity or not

[@plenum88]

I would say no, it doesn't prove special relativity (SR), since the speed of light in the device is shown to be C-v or C+v in the frame of the rotating observer. If SR can't be applied to rotating observers due to it's restriction to "inertial frames of reference", then it can't contribute anything to the explanation of the Sagnac effect. This may explain why Einstein avoided discussing the Sagnac effect.