Endless belt and release physics

[Jeff]

Mike

You wrote-: "But I would think that if there was anything that you would say that the clubshaft is release with respect to - it would be the ball- in regards to what forces will be created and not the hands (if that gets the discussion off base in regards to the context that you are discussing - just ignore it for now)."

When you want to relate the release of the clubshaft with respect to the ball, then you are discussing a totally different subject. I am simply trying to understand the physics of the release phenomenon - the reason why the clubshaft releases in the mid/late downswing (the reason why power accumulator number #2 releases). It is also equivalent to understanding the physics of the flail release - why the end swingle stick releases when the central stick is swung smoothly along a curved path.

HK used the endless belt analogy to explain the clubshaft's release phenomenon. He uses the analogy of ducks (equivalent to a clubshaft) on a belt at a fairground. The belt travels at constant speed, which means that the ducks (which are attached at their foot-base to the endless belt) travel at the same speed as the belt - during the straight line travel section of the endless belt. When the belt swings around the pulley at either end, then the ducks have to swing around so that their upper end (head-end) travels faster than their lower end (foot-end). In other words, the ducks are angularly accelerated during the time period when the belt (traveling at constant speed) swings around the end pulley. HK's endless belt analogy is a nice visual concept to explain how a club can be angularly accelerated when its attachment point (to the hands) goes around a bend. However, the endless belt concept only makes maximum sense if the attachment point (hands) moves quite abruptly from a straight line path to a curved path (eg. along a J-shaped curve). It doesn't explain how clubshaft release can occur with a C-shaped curve (Bobby Jones swing) or a circular curve (PingMan machine). nm golfers' single mathematical explanation can explain all those release phenomena equally well.

When I stated that the clubshaft cannot be conceived to be rotating in a circular fashion around point "X", I basically meant the following. The concept of angular acceleration of a linear object (rather than a point-object) generally relates the angular movement of the linear object to its "fixed" lower end, which must be at the center of a circle, while the peripheral end is always on the circumference of that circle. In that diagram, point "X" is the center of a circle relating to certain point-objects (hands or clubhead end of the clubshaft), but the linear object (entire clubshaft) has no constant circular rotational relationship to "point X" because an extension line drawn from the butt end of the club doesn't pass through point "X". From my perspective, the concept of angular acceleration of the clubshaft only makes sense with respect to its "fixed" point of attachment - which is at the hands.

Jeff.