The primary developer of the algorithms used in the Yamaha VL instruments is Toshifumi Kunimoto. He is the listed 'inventor' for almost all of the patents listed below. Those of you interested in the algorithmic details of practical physical modeling of musical instruments can consult the full text of the patents below. Patent titles are omitted, as not being particularly descriptive or useful. In general, they are all about numerical algorithms for producing musical effects using physical modeling. The patents here are listed in chronological order. The development work chronicled in these patents seems to have gotten going in earnest in 1989.
The USPTO site It was slow to arrive, but this is the REAL DEAL. On the page linked, under Full Text Database, click Boolean Search. From there you can probably figure it out. Clicking on a patent in the result list gives you full text, albeit in very wide-formatted pages. Resize your browser window to make it a more suitable column width. Then if you click the Images button (top or bottom of page) you can see the diagrams and such also. To do this you will need a tiff viewer, which you can download from a link from Netscape or Microsoft. If you use a tiff viewer, you will have to download entire page images (including text) as 300 dpi tiffs, which is slow unless you have a big pipe, so view the text without the tiff viewer. If you have not researched patents before, a quick caveat: the claim section of patents is written in legalese, and you will probably find it tough sledding. The patents below have some interesting diagrams and descriptions, though, so if you are determined, you can learn some 'inside info' from them. You might like to study Manny's VL Ex Editor manual first, though, and perhaps cruise the CCRMA site for some tutorial materials first.