Copyright © 2016
by Full-Measure Response, Inc.
All Rights reserved
rvoit@keyforceone.com
Enabling your customers to experience the ultimate in keyboard continuity
Kinetic Detection of Keystroke Events & Objects
     One of the great things about this technology is that the resulting contin-
uous forces allow all sorts of things - both events, objects, and deformation of
those objects - to be detected and characterized.  Just imagine a simple down-
stroke of the KF1 's finger, with a zero point well above the at-rest keytop.  As
the finger moves down, it will (a) collide with the key itself, (b) experience the
significant resistance of the damper engaging, (c) experience the strange
resistance of the entire escapement event, and (d) experience the collision
and compression as the key bottoms out against the front punching.  Along
the way, it also experiences the continuous gravitational and frictional (iner-
tial if the key is accelerating) resistance of the key action being excited.  Most
of the routines performed by the KeyForce 1 don't experience (b), because the
dampers are disengaged beforehand.  However, the available Damper Force &
Timing product requires routines that perform both up- and downstrokes with
the damper engaged.
 
     One of the most innovative functionalities available with the KF1 is the
patented Key Return Time measurement.  It consists of a very quick upstroke,
with the finger starting in a "key-depressed" position.  After ascending  5.3 mm
very quickly, to a point very near at-rest position, the finger simply waits for the
key itself to catch up with it.  Forces are being measured and recorded, and the
resulting collision event leaves a telltale, synchronized force signature.  The time
required for the key to rise is automatically extracted from this signature.  While
the thing being detected by the KF1 is the rising key, what is ultimately being de-
tected is the end of the "key return" event, thus yielding the KRT in milliseconds.
Please click the icon at right to learn more about Key Return Time, including its
fundamental connection with key action balancing and true Inertia at the Key.
     A dedicated routine that has the finger performing a quick downstroke, from
a zero point slightly above the at-rest key forms a central part of the KeyForce 1's
Kinetic Key Leveling functionality.  The stroke is large enough to ensure
that the at-rest key is collided with.  The continuous stream of resulting forces
is examined quickly to determine the very beginning of the collision event.
With forces synchronized, this collision time corresponds to an exact distance
as well, relative to the global zero plane.  This is the clearance from the plane
to the at-rest key.
     The other half of Kinetic Key Leveling consists of finding the ever-dubious
"bottom" of the keystroke (the Key Dip essentially).  The KeyForce 1 's finger
begins a fairly slow downstroke, from the same zero plane used for finding the
at-rest key position.  With forces being constantly measured, the program
looks for the telltale signs of the front punching being compressed, filtering
out all other resisting events (namely, escapement).  An actual force versus
deformation curve is quickly produced.  The so-called bottom - or key dip -
point is extracted right from this deformation curve!  This innovative process
likely yields the most consistent, least dubious key dip point in the industry.
Of course, the deformation curve itself is extremely useful itself, producing
a wealth of front punching stiffness information for each and every note.
With both routines completed, they are repeated for all notes across the action,
with the zero point/plane remaining just above the highest same-colored key.
To see real-world examples, please click the link at right to get to the Key Level-
ing product page. 
     Another very important event that the KeyForce 1 detects and quantifies
is the escapement, or let-off event.   When performing a "let-off routine",
the KF 1's finger moves downwardly at constant speed, all the way to the bottom
of the stroke.  It therefore measures not only the continuous Down Forces occur-
ring before let-off, but also the important forces that occur due to escapement
itself.  Various parameters have been created to characterize the let-off event, in
terms of both location/travel and reaction forces.  Please click the link at right
to read an article explaining these valuable "let-off" parameters, and how they
more fully leveraged when shown along with the key leveling data.  This is nearly
identical to the article appearing in the April 2014 issue of the PTG Journal.  This
routine is part of our
FLA
(Forces-Letoff-Aftertouch) product.  Please click the
gear icon just below to learn about that particular product.
     Another important event detected and quantified by the KeyForce 1 - in a very
similar manner as with the let-off event - is the damper event.   Unlike the let-
off event, the damper event does not conclude.  Once the damper engages, it stays
engaged for the duration of that downstroke.  The
Key Force 1 sees and records
all of the reaction forces brought on by the damper engagement, both in the down
and up directions.  Important damper down force, damper up force and damper
friction force values are obtained from these measurements.  And of course, the
all-important damper engagement point is located for each note.  Please click
the link at right to see an in-depth article on this technology, and its application
thanks to the Key Force 1.  You may also click the link below to visit the Damper
Product page, which has more information and product samples.
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