FRESH

Hacker News

Vibration Isolation of Precision Objects (2005) [pdf]

26 points by nill0

by lanthade

0 subcomment

Back 30 odd years ago I was doing work with a graduate/post graduate chem-e/material science group at the U of MN. I was working with a PhD candidate who was working on synthetic insulin. Part of the project was attempting to use a scanning tunneling microscope (STM) to image insulin at the molecular level. I hadn't ever done work with STM before and part of showing proficiency with the tool was to image Highly Oriented Pyrolytic Graphite (HOPG) at the molecular level. As you can imagine almost any vibration will show up when you're working on the scale where you measure in angstroms.
To solve for the vibration issue the STM lab was in the basement of the building and the STM equipment sat on a multi-ton granite block that was suspended from the ceiling of the building. The building sits in the center of the U of MN campus right next to a major roadway so there were lots of opportunities for vibrations to enter into the structure.
One of the coolest feelings was the day that I successfully imaged HOPG at the molecular level. To point at the image on screen and be able to say "That's a carbon atom!" is insanely cool. I didn't end up staying in chem-e but the experience of working in a real research lab with highly intelligent and creative people has impacted my life in numerous ways.

by Scene_Cast2

0 subcomment

Tangentially related - I was doing some highly sensitive analog electronics work. It's surprisingly hard to find capacitors that don't exhibit microphonic behavior - i.e. they don't produce (miniature) voltage swings when you tap the PCB.