# Open-Source Nanoactuator Design Utilizing Hard Disk Drive Components

**Byline:** Ro Kirchev, Jacob Fenwick, Cara Mico · Coast Desk  
**Class:** Essay  
**Status:** Web excerpt; full paper on Drive  
**Dateline:** Studio 45 Hardware AI Robotics Hackathon · Feb. 25, 2024

**Source:** [Google Doc](https://docs.google.com/document/d/1dIuwaTT61dO80JjgL-GSj44diTHXh7L8Vfkq1je_nNw/edit)

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Precision displacement measurement with a Michelson interferometer — a cheap nanoactuator from disc-drive parts, measured on a DIY optical table under $400.

High-precision nanopositioning tools matter in microelectronics, photonics, and materials science. They are also expensive. This paper describes a nanoactuator built from off-the-shelf parts inside a conventional laser-disc / hard-disk drive mechanism, with displacement read by a Michelson interferometer.

The aim is to reuse the precision already designed into disc-drive mechanics and put piezoelectric crystals where the head gimbal used to sit. Preliminary results were promising and also blunt: without a vibration-isolated platform, nanometer placement cannot be measured cleanly.

## What was built

Salvaged actuator arms, the drive’s voice-coil motor, a precision pivot bearing, a flex circuit, a voltage divider, a Michelson interferometer, and a magnet to turn rotation into linear travel. The measurement the title names is a 200 nm step.

## Limit

The actuators moved. The missing optical table made the measurement noisy. The $400 table is the other prototype. The experiment was still in progress at filing. The claim on the page is the method and the parts list, not a finished commercial stage.