…I’m using it to develop new curriculum for the Jacobs 3D Initiative, and to research the real “causes” of a swing. It’s an exciting time to be studying the golf swing! Over the past 20 years, Mechanical Engineer Dr Steven Nesbit has conducted the most influential research in the history of our sport. As a researcher for the USGA he conducted research on equipment, the actions that the golfer applies to the club during a swing and a full biomechanics study on the human body during a golf swing. His research has shaped the rules of the game and the understanding of how the golfer moves their club and body in a swing. After his work with the USGA, he went on to study other sports like baseball and tennis. Other than a few ‘student interest’ research papers his work was dormant in the published papers and unpublished studies at the USGA. In 2010, I met Dr Steven Nesbit and we discussed and studied his prior research and he was very intrigued to see a dedicated golf pro applying the findings and conclusions of his studies. I was experiencing unparalleled success learning and applying the physics of the golf swing and the biomechanics of the human body. Steve’s interest in golf research was reinvigorated in 2014 when we decided to launch a new layer of research together with the commission of the Jacobs 3D golf swing analysis software. Our new software platform Jacobs 3D, evaluates both the kinematics and kinetics of the golfer. You can break a golf swing down into those 2 categories BUT the kinetics category had never been attempted before by a golf teacher.
Kinematics describe the movements of a golf swing (speed, velocity, acceleration, rotation, etc)
Kinetics are the forces that created the movement (forces, torques)
Traditional software packages are great at measuring kinematics (movement) but they don’t show the kinetics, or forces at play. For example, I could already see kinematically the motion of the club twisting on the downswing as the player squared the face. I could see that it twisted, and how fast it was twisting, but I wanted to know how much force/torque it took the player to twist it, and when in the swing that twisting effort started to happen. The ability to do that wasn’t out there, so I decided to solve the problem myself. I built my own software—Jacobs 3D. One of the Fundamental Elements of the golf swing is the force that the golfer applies to the grip when they move the club throughout the motion. In the Fundamental Book, we discussed and displayed many examples of the sum of the forces applied to the grip from the golfer. This ‘linear’ force is continually changing directions as it moves around in a curved path.
The force, which is the predominate action supplied by the golfer, is categorized as the ‘linear’ component of the swing. The sum of the forces can be broken down into components. In our convention of analysis, we have several different coordinate systems to analyze the components of the linear force. The Master Elements cover those components.
The force applied to the grip also plays a big role in how the club rotates during a golf swing. The rotation of the club, ‘angular component’ of the swing, is directly effected by the direction of the force that the golfer applies. How the club rotationally responds to the force you apply, will directly effect your options for applying torque to the club.
Your applied torque is also effected by the rotational resistance of the club at each instant in time. The rotational inertia of the club is very interesting and requires tracking what point the club is rotating around and how that changes throughout the swing. Inertia about this point is a true indicator of what the golfer actually experienced. All of these items wrapped together are the ‘truths’ of the golf swing.
In the Fundamental Book, we broke the rotation of the club down into 3 components: Alpha, Beta, Gamma. We also described and displayed how several golfers were applying their torque to the grip point to influence the angular movement of the club.
The Kinetics just described are what create the kinematics. - Michael Jacobs, PGA | www.jacobs3d.com