Phil's Senior Project!
The goal of my senior project is to create a mechanism which will modify an existing piano to "bow" the strings of the piano similar to the way the violin does this. There are essentially three different ways in which a string under tension can make sound. These are: plucking, as a harpsichord or a harp does, striking, as a piano, or bowing, as any of the violin family of instruments. The first two methods already exist in an automated system using the keyboard common to the piano, harpsichord, and organ. The third has not been done this way.
My design involves using a rotating cylinder with good bearing properties and high roughness to rub against the strings. The cylinder will be driven with a friction drive, using a belt which goes transverse to the strings. A system of levers, made from wood in the same manner as current piano parts, will be used to push the cylinder into the string in a prescribed manner. The purpose for using this method as opposed to using motors or actuators in conjunction with a control system is to allow for the greatest possible control by the player. Such control can only be achieved when there is a direct connection between the player's fingers and the bow. Also, simplicity and packaging play a significant role in the effective manufacture of this system.
The current design is specifically made for the upright piano to which I have access, although it could easily be placed into other uprights with minimal modification. Since I do not have access to a grand piano, I do not know how well it could be modified for one, although I believe it could be made to work in a similar way.
This model was created using AutoCAD Release 12 and AutoCAD Designer. The Geometry was then exported to 3D Studio Release 3, where I applied the texture and did the final rendering. The model is to scale, and is an accurate representation of the inside of the upright piano I am using in all of the important details.
I completed this project, and it actually looks a great deal like the computer rendered picture! It needs some improvement, however, as the spinning cylinder turns out not to bow the strings as well as could be hoped with the material it is using. A better material could solve this problem. Also, the mechanism is noisy, a highly undesirable effect in a musical instrument. The idea still holds promise, however, and I intend to continue working on it for some time.
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