I have a few issues with the claims or omissions made regarding this instrument. The piano forte wasn't invented until the 18th century. A few people have alr

I have a few issues with the claims or omissions made regarding this instrument. The piano forte wasn't invented until the 18th century. A few people have already mentioned that the hurdy-gurdy is very similar in function to this instrument. This instrument looks like four hurdy-gurdies stacked for an extended octal range stuck inside a piano enclosure. So what exactly was Da Vinci's contribution to this instrument and how much of Da Vinci's design was "augmented" by the builders?