Post by imperfectgolfer on Jan 25, 2012 10:58:39 GMT -5
In 3jack's forum, a forum member asked "what is meant by going normal".
Greg answered-: "Well I actually am not understanding much of it other than you want the the wrist to bend as you approach impact and the left wrist should bend immediately after impact so the club lines up with the right arm at about P7.5. The club should always be perpendicular to the arc of the swing. This is the optimal, and the way most pro's swing the club."
It has nothing to with the motion of the wrists through impact.
Thanks to more Skype video interactions with Sasho MacKenzie, I have now finally understood the "normal" concept and I am actively writing a new review paper on BM's release ideas, where I will explain the entire issue in great detail.
Going normal happens in all golf swings - even if the hub path radius remains constant (eg. Iron Byron machine).
Here is photo from the Miura article plotted from a double pendulum swing model.
Note that the hand arc path is perfectly circular, and that the golfer goes normal in the last 0.04 seconds of the downswing (starting at roughly P6.5) generating a normal force of 414 nM at low point. "Going normal" has nothing to do with a shortening of the hub path radius near impact and it is due to the unloading of the club in the last 0.04 seconds of the downswing. A golfer has to go normal to provide a centripetally-directed force in order to counteract the effect of centrifugal loading of the club. Three major factors affect the magnitude of the normal force in the last 0.04 seconds of the downswing - clubhead velocity, mass of the club, and degree of angulation of the clubshaft relative to the hub path. Shortening of the hub radius only plays a role if a golfer uses parametric acceleration by pulling the club upwards near-impact -thereby shortening the hub path radius.
Note that the normal force arrows are always drawn along the longitudinal axis of the clubshaft in the last 0.04 seconds of the downswing.
Steve Nesbit even admits to this interpretation in his hub path paper. He wrote-: "During phase III the tangential force drops toward zero while the normal force increases to maximum values at ball contact. The primary action of the linear force during this phase is controlling the path and reacting to the large centrifugal loading from the club as it reaches its maximum club head velocity and coincident minimum hub radius".
Jeff.
Greg answered-: "Well I actually am not understanding much of it other than you want the the wrist to bend as you approach impact and the left wrist should bend immediately after impact so the club lines up with the right arm at about P7.5. The club should always be perpendicular to the arc of the swing. This is the optimal, and the way most pro's swing the club."
It has nothing to with the motion of the wrists through impact.
Thanks to more Skype video interactions with Sasho MacKenzie, I have now finally understood the "normal" concept and I am actively writing a new review paper on BM's release ideas, where I will explain the entire issue in great detail.
Going normal happens in all golf swings - even if the hub path radius remains constant (eg. Iron Byron machine).
Here is photo from the Miura article plotted from a double pendulum swing model.
Note that the hand arc path is perfectly circular, and that the golfer goes normal in the last 0.04 seconds of the downswing (starting at roughly P6.5) generating a normal force of 414 nM at low point. "Going normal" has nothing to do with a shortening of the hub path radius near impact and it is due to the unloading of the club in the last 0.04 seconds of the downswing. A golfer has to go normal to provide a centripetally-directed force in order to counteract the effect of centrifugal loading of the club. Three major factors affect the magnitude of the normal force in the last 0.04 seconds of the downswing - clubhead velocity, mass of the club, and degree of angulation of the clubshaft relative to the hub path. Shortening of the hub radius only plays a role if a golfer uses parametric acceleration by pulling the club upwards near-impact -thereby shortening the hub path radius.
Note that the normal force arrows are always drawn along the longitudinal axis of the clubshaft in the last 0.04 seconds of the downswing.
Steve Nesbit even admits to this interpretation in his hub path paper. He wrote-: "During phase III the tangential force drops toward zero while the normal force increases to maximum values at ball contact. The primary action of the linear force during this phase is controlling the path and reacting to the large centrifugal loading from the club as it reaches its maximum club head velocity and coincident minimum hub radius".
Jeff.