Piano Roll Scanner Project (PRSP)

February 24, 2016
Jerry L McBride
Roll scanner model

To facilitate research, study, and access to the historical piano rolls in its collection, the Stanford Player Piano Project is designing and constructing a piano roll scanner capable of scanning all of the various types of piano and organ rolls that have been collected to date. This new scanner is based on the work of Anthony Robinson, who is working with the Project to expand upon and improve his earlier design. Monica Caravias, a graduate student at the Stanford Product Realization Lab, is designing and building Stanford’s scanner in close collaboration with Anthony and under the direction of Prof. Craig Milroy. This is the first in a series of reports on the progress of constructing the scanner.

The hardware manufacturing for the Piano Roll Scanner Project (PRSP) is off to a quick start this quarter. Parts have been ordered, a CAD model of the design has captured the core parts of the mechanism, and key elements are in the preliminary stages of fabrication.

Piano roll scanners have been successfully implemented by hobbyists and research institutions, but are not at the level of refinement that would allow the Stanford Archive of Recorded Sound to conveniently scan their large collection. The PRSP hopes to improve upon these current designs in a few key ways. Most importantly, the scanner needs to accommodate a wide variety of roll geometries. Rolls vary in their width (from about 10 inches to over 15 inches) and the shape of their end caps, which are used to hold them in a player and drive their rotation. A preliminary CAD model of what the scanner may look like is shown below:

One important feature of this design is the inclusion of interchangeable end holders, which enable the user to quickly modify the scanner to accommodate different piano roll geometries. Upwards of 10 unique pieces will be machined in order to interface with different rolls, and will be assembled into a bearing system that allows the roll to rotate with very little resistance. These assemblies are magnetically attached to the main body of the scanner, so the user can quickly remove and replace them. 

Another important aspect of the design is the flexibility of roll positioning. The user will be able to move and lock the uprights that keep the roll in place via a slotted track, enabling the scanner to hold rolls up to 20 inches wide. Other components are similarly transformable, such as the take-up spool that the roll is wound on to.

--Monica Caravias and Jerry McBride