Hi,  A few years ago the GSM (the German society of self-playing
musical instruments) had their yearly meeting in Vienna, Austria.
A conducted tour of the Bösendorfer piano factory was arranged.
I remember that they had a soundproof room for a first test of the
pianos by a robot.  Each key (a few dozen simultaneously) was pushed
down by a robot a few hundred or thousand times.  But I can't remember
exactly what they told us about how many times the robot pushed down
a key.

Kind regards,
Hauke Marxsen, Germany