This is a multi-part message in MIME format. ---------------------- multipart/alternative attachment It would be difficult to come up with a complete dynamic model -- one = that would predict behavior, given a set of inputs. However it would be easier, and a necessary first step to the = development of the model, to measure this finger pressure during the entire keystroke, = as Phil describes below. Graphed over time, it should show lost motion, = hammer movement, escape, and aftertouch. Add the force of the hammer on the string, and you've got the complete envelope of the mechanical inputs = and outputs of the action (well, save for the dampers). Car magazines publish graphs of car engine performance; wouldn't it be useful to have graphs like this for a range of test blows from ppp to = fff? They could be used to classify actions into categories like "light" to "firm", as was suggested. Piano manufacturers have robotic players to settle the action which = could be programmed for a series of test blows, as well as the various player mechanisms (although the former might better simulate a real finger = pressing a key). Do manufacturers take dynamic measurements as well? --Cy Shuster-- Rochester, MN >On Friday, May 2, 2003, at 12:48 PM, Phillip Ford wrote: > As I see it this will be one of the problems that Stephen Birkett (or > any other contenders) faces in making a dynamic model of an action. > What input are you going to use? Does the player push down with > constant force? With constant velocity? With constant acceleration? > Does he push down with more force initially to break the static > friction and then back off to a lower force? Does he attempt to > rapidly accelerate the key in the first part of the movement and then > maintain a constant velocity for the rest of the > movement? ---------------------- multipart/alternative attachment An HTML attachment was scrubbed... URL: https://www.moypiano.com/ptg/pianotech.php/attachments/84/e4/bc/5d/attachment.htm ---------------------- multipart/alternative attachment--
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