Posted by: Jack Mankin (MrBatspeed@aol.com) on Tue Sep 12 08:26:14 2006

>>> How did you test the forward momentum of the mass of the hitter? If you look at the biomechanics of dropping your front heel to swing (no one swings flat footed) the mass of the body must move forward towards the front leg because if it does not then you have come to a static position. You can not move fast from a static position.

Please answer the first question because while I was in university we did test for this but not with hitters but with other movements. It was not something that you could just look at a video and determine. <<<

Dave P

Hi Dave

What equipment did you use and at what university? The reason asked is you may have used the same type of Motion Studies equipment we used at the University of California, San Bernardino. That equipment had an array of motion detectors and pressure censors hooked up to a Motion Studies Computer (I will place below a post describing the equipment). When I worked with the equipment, they had not installed the large pressure censor pads that was to be used for spotting problems in walking, running, dance and etc.

We only had the use of small test pressure censor pads (about 12 by 5 inches). The computer did show the areas of the foot where the greatest pressure was being exerted but not exact readings. I understand the equipment has since been upgraded to give accurate pressure reading for different areas of the foot. – Zig was probably using similar equipment to get his readings.

We used the computer’s motion detectors array to determine momentum transferred. Momentum is the product of a bodies mass and its velocity. Once we are given the velocity of the center of mass, we can determine its momentum at any point of the swing. The computer can give us the angular and linear velocity vectors for any point on the body we choose.

Jack Mankin
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Posted by: Jack Mankin (MrBatspeed@aol.com) on Thu Mar 6 00:43:59 2003

Hi Zig

I am aware of the hard work and dedication you put into your project and you are to be commended for it. During 1996-7, we ran a similar study at the U of CA (San Bernardino) using their newly acquired Motion Study computer with 4 position motion detectors, pressure sensors and high-speed cameras. Sensor points (looked like miniature Ping-Pong balls) were placed at each joint of the batter's body and the linear velocity and angular displacement rate for any limb (or joint) at any point of the swing could be analyzed.

Zig, I am sure the data from our study would confirm the findings you just presented. After analyzing your data, does a batting principle emerge that has not been published or discussed on this and other sites? With the pool of batters we had to work with, I could not find predictable correlation’s between the angular rate of the various sensor points and bat speed development.

Jack