More Gravimeters, now with piezo film and single lens interferometers

https://www.researchgate.net/project/iLens-Interferometer-towards-a-new-class-of-frugal-devices

I’m interested in this research – could you provide the full-text for it?
– Richard Collins

I was searching arxiv.org for “piezoelectric film” “piezo film” which can be used for low cost vibration and acceleration measurements. I want to use it for a sensitive three axis gravimeter at high sampling rates. I found your article at https://arxiv.org/abs/1909.09340 and followed it to ResearchGate. I hope you will fill in something on your force measurement project.

MEMS accelerometers are sensitive enough to track the sun and moon by its tidal gravity signal. But they are too slow for time of flight verification methods. Accelerometers sensitive enough to track the sun and moon tidal signal are OK to call “gravimeters”.

Richard Collins, Houston Texas


Laser diode self-mixing: Range-finding and sub-micron vibration measurement

I was looking at piezoelectric films (aka piezo film) detectors today for vibration, acceleration and other applications.

I searched arxiv.org for them, and found this paper that is related to what Ben was trying to do with the laser self-mixing – measure precisely with just a single sensor element. I like their concept “ultra-precise frugal photonic devices”

A single-lens universal interferometer: Towards a class of frugal optical devices
https://arxiv.org/abs/1909.09340 – for the abstract
https://arxiv.org/pdf/1909.09340 – for the PDF


Are you still listening? Can this be used without a massively expensive oscilloscope? If the data you are showing on the screen can be captured, I can use it to give very precise measurements. Well beyond eyeballing an oscilloscope. I need three of these to monitor a pendulum for a classroom project to monitor the sun and moon.

https://hackaday.io/project/164550-low-cost-3-axis-high-sampling-rate-gravimeter
https://www.youtube.com/watch?v=wB_xwUdf2mw&t=1512s – using seismometers as gravimeters to track the sun and moon
https://www.youtube.com/watch?v=JwNTwxgAJkM&t=1506s – Spatial resolution of gravimeter imaging arrays

Almost forgot. Way cool!!! Very very elegant. I suppose you can use any laser diode and add a feedback photodiode without having to try to find one? When the reflected beam intensity is fed back to control the intensity, it will only depend on the the difference in path length from diode to surface, surface to photodiode, as a long as the photodiode feedback is fast. ??

 

Richard K Collins

About: Richard K Collins

Director, The Internet Foundation Studying formation and optimized collaboration of global communities. Applying the Internet to solve global problems and build sustainable communities. Internet policies, standards and best practices.


Leave a Reply

Your email address will not be published.