I Problems with Blum's Karate Article

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Concerns were raised about Haywood Blum's article "Physics and the art of kicking and punching," particularly regarding his use of a beam model instead of a mass impacting the center, and the choice of beam over a flat plate. Additionally, the article fails to account for wood's orthotropic properties, relying instead on isotropic material formulas. Access to the article has become difficult, as no free PDF is currently available online for review. A related article on the biomechanics of a knockout punch was mentioned, though it does not address striking a target. Overall, these issues highlight significant gaps in Blum's analysis of martial arts physics.
makamo66
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I have a couple of concerns with Haywood Blum's article "Physics and the art of kicking and punching." First of all, Blum considers a beam with a couple applied to the ends of the bar when he should be considering some kind of mass impacting the bar in the center and second of all, why does he use a beam and not a flat plate? Also, he doesn't take into consideration that wood is orthotropic and simply uses the formulas for an isotropic material. Unfortunately I couldn't find a free PDF of this article online any more but I was able to download the PDF at some time before.
 
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