Acceleration profiles? (with page two presentation by Mike Jacobs)

[Michael Jacobs]

This however doesn't answer some of the the old questions posted here some time ago

- Why is the acceleration show in G (gravitational acceleration) and not in sec^2? Is it because it has a relation with the downward direction? Also unclear is how this "value" has been "measured" or is it an calculation based on the delta's in measured speed (downward direction?) and then divided by distance and g ?

- What is that distance? Is it vertical/horizontal or distance along it's swing path? If it is the last then it would be calculated backwards from impact? Because final path is only know when impact takes place.

- If TM explains that clubhead impact speed is hard to measure because of the difference in speed between toe and heel, what is the error margin in this chart?

that's all

I will not start the discussion about the shaft fitting part......yet..

Those we discuss at Flightscope Conventions.. perhaps you should attend

 

[Michael Jacobs]

Westwood was hitting his 6i 150 yards? Am I reading that correctly?

Thats the club that was labeled, whether or not it was labeled with the correct club number or not I don't know. That is why I included the Driver profiles

 

[Frans@France]

Those we discuss at Flightscope Conventions.. perhaps you should attend

maybe you would be so kind to anwer? Those questions where posted here on this forum before and no aswer was placed by those that know....

 

[Frans@France]

Seems to me that the acceleration profiles from lee westwood and harrington are not from the same club. So comparing the smoothness of those two profiles is not logical.

 

[Michael Jacobs]

Seems to me that the acceleration profiles from lee westwood and harrington are not from the same club. So comparing the smoothness of those two profiles is not logical.

That makes no sense what so ever.. its their own driver that they were using at the time.

 

[ParHunter]

This however doesn't answer some of the the old questions posted here some time ago

- Why is the acceleration show in G (gravitational acceleration) and not in sec^2? Is it because it has a relation with the downward direction? Also unclear is how this "value" has been "measured" or is it an calculation based on the delta's in measured speed (downward direction?) and then divided by distance and g ?

g itself is in m/s^2.
1g=9.81 m/s^2, so you could just as well multiply the figures on the y-axis by 9.81 and you've got your m/s^2
g doesn't have to be downward, the acceleration can happen in any direction.

Edit: for people preferring imperial measurements: 9.81 m/s^2 = 32.2ft/s^2

 

[Frans@France]

g itself is in m/s^2.
1g=9.81 m/s^2, so you could just as well multiply the figures on the y-axis by 9.81 and you've got your m/s^2
g doesn't have to be downward, the acceleration can happen in any direction.

You're missing the point. it's not how you can MIGHT get from "G" to m/s^2 using "g", the question is why EDH decided to use this unit "G" to present the data on the y-axis.

 

[Frans@France]

That makes no sense what so ever.. its their own driver that they were using at the time.

sorry, I tried to say "not the same club type" Seems to me that that exit point in the graph @ ~37G (Lee) would not be the same type of club that has an exit point @ ~75G(Padraigh)

 

[Michael Jacobs]

sorry, I tried to say "not the same club type" Seems to me that that exit point in the graph @ ~37G (Lee) would not be the same type of club that has an exit point @ ~75G(Padraigh)

The pre impact point is different for every golfer. They were both hitting driver there

 

[Frans@France]

The pre impact point is different for every golfer. They were both hitting driver there

Thanks for letting know. Do you also have the clubhead speeds for those same shots?

 

[ParHunter]

You're missing the point. it's not how you can MIGHT get from "G" to m/s^2 using "g", the question is why EDH decided to use this unit "G" to present the data on the y-axis.

I guess with g the user has something to relate to. Hardly any normal golfer would know what m/s^2 actually means while they might have heard of g. Just guessing here

 

[Michael Jacobs]

Thanks for letting know. Do you also have the clubhead speeds for those same shots?

Its in the speed profile pictures... Only you would have problems with a Tutorial showing people how to read the charts.

 

[Frans@France]

Its in the speed profile pictures... Only you would have problems with a Tutorial showing people how to read the charts.

relax, I only saw brian's images and not yours. But indeed the speed charts are included in your posting. Thanks!

 

[Frans@France]

I guess with g the user has something to relate to. Hardly any normal golfer would know what m/s^2 actually means while they might have heard of g. Just guessing here

It's not the "normal golfer" operating the unit but an operator who's job it is to understand the data deliverd by the unit.

My personal guess is that G is used because the data doesn't present the acceleration of the head along it's swing path but calculated acceleration using "bird-fly" distance (the distance between LM and clubhead related back to impact point). So not acceleration in "xyz" space but only a part of space (xy?)..... only guessing here.....

 

[Frans@France]

In the speed profile between -20 till -15 inch before impact the speed remains almost the same. If the acceleration profile is from the same serie of shots why is the G not reaching zero?

I digitized the speed profile above but no way I can even get close to the acceleration profile, already expected that it would not fit really good for reasons explained already by Mandrin but not even close was a bit of a suprise

So who has the answer about this G graph?

Before I get negative comments...I'm here to learn and learning how Launch Monitors work is part of that. Telling that G equals "force of gravity" is not enough.

 

[tongzilla]

Mike, does the same methods of interpretation apply for irons?

 

[GaryC_47]

In the speed profile between -20 till -15 inch before impact the speed remains almost the same. If the acceleration profile is from the same serie of shots why is the G not reaching zero?

I would assume that some form of smoothing or curve fitting algorithm is being applied to the data points to eliminate the "noise."

Gary