OttoMate is the companion app for Otto, the Franz diffusion cell autosampler robot. It is used to generate G-code to programme Otto.
I wrote OttoMate as a browser-based app to maximise portability. It's just a static HTML file with JavaScript. It can be hosted on a web server, or opened as a local file on a client computer. It can be run in any modern web browser on any hardware that supports the web browser.
The initial release (v1.0) coincided with the publication of the paper that describes how Otto was put together (Ng et al., 2026, see below). If you have assembled Otto based on the description in that paper, you should use release v1.0. Later versions may not be compatible with that particular hardware configuration.
Otto was conceived and developed as part of an academic resesarch project to automate laboratory workflow. As a scientist, I develop pharmaceutical formulations for the skin. The Franz diffusion cell is a laboratory apparatus used to evaluate drug absorption in the skin. It is usually operated manually, which comes with some drawbacks. My team and I developed Otto to overcome those limitations.
To learn more about Otto, please read the following academic papers. If you have used Otto in your work, please cite these papers when publishing said work:
- Ng KW, Archbold L, Lau WM. Building Otto: An open-source Franz diffusion cell autosampler for automating in vitro skin permeation studies. HardwareX, 2026;25:e00735. https://doi.org/10.1016/j.ohx.2025.e00735
- Chan HKY, Archbold L, Lau WM, Ng KW. Validating Otto: a Franz diffusion cell autosampler to automate in vitro permeation studies, J Pharm Sci. 2025;114(7):103837. https://doi.org/10.1016/j.xphs.2025.103837
- Ng KW. Design files for Otto, the Franz diffusion cell autosampling robot. Mendeley Data. https://doi.org/10.17632/cvc9vxjgn9
There are also these YouTube videos about Otto.