If you are unfamiliar with the Pitch Trajectory simulator UMBA, please visit our page about it here.
You can download UMBA 1.0 here
As of now, we don’t know enough about things like spin decay, spin axis changes during flight, seam height, scuffs, and of course seam orientation to model them. We will take better data into account as more data becomes available.
For this first pass, I used a simple drag model that considers the coefficient of drag to be constant. That is, were not taking the drag crisis into account. This is a VERY simple model that needs to be refined in later iterations of the program. For now, it is sufficient for most pitched balls with the exception of something like, maybe, the Eephus pitch.
For lift from Magnus, I used the same model as Professor Nathan which comes from Rod Cross’s book Physics of Baseball & Softball. This is an acceptable model although, Jeff Kensrud at Washington State’s Sports Science Lab published a paper of the drag and lift generated by various sports balls. These results could be used to create more refined models for lift and drag. This is likely my next step.
When I go to download I get just a bunch of code stuff I don’t understand.
Jake,
It might be difficult to run if you have no experience with coding. However, if you are willing to try a little you can download and install anaconda from this website https://www.anaconda.com/distribution/ and run spyder. Once you are running spyder you simply need to open the umba.py file and hit run.