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Unread 10-01-2014, 18:13
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MechE
AKA: Craig Rochester
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Re: Ball Flight Model

Quote:
Originally Posted by NotInControl View Post
So as promised, I have included some additional data sets to test for your model.

I have yet to confirm the results to actual measured results from the balls flight trajectories.

Once again my model only includes air resistance no magnus force. All Paramters needed should be included on the plots.

The ball in the plot is to scale.

The only trouble I am having is determining the required force based on the lauch velocity. The numbers are way to small in my opinion. Maybe it is because using Vf = Vi + at assumes accel is constant over time and because I assume the force is applied over t=0.5 seconds which may be too long.

I don't know, I haven't spent time looking into it. But I would expect the required force to be in the 100lbf+ range for quick shots. Any thoughts?

Hope this helps,
Kevin
Hi Kevin,

thanks so much for the charts!

I'm working on modelling a mechanical linkage to pneumatic cylinder with:
  1. Force of accelerating ball at end of long member
  2. Calculation of airflow to cylinder using 0.3 Cv
  3. Rate of travel of cylinder rod (piston)

I'm thinking that the limitation of the pneumatic's flow capacity can be addressed by the progressive increase in ball speed vs. piston speed via a linkage design. See video below:http://youtu.be/DaTn6ZMzihw

I'm not sure I follow your question regarding acceleration. Could you provide more detail?

Regards,

Craig