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Dan Russell (Dr. Batman)

@drussellpsu.bsky.social

Teaching Professor of Acoustics. Penn State. Acoustics Education. Research on vibrio-acoustics of sports equipment (baseball/softball bats, gold clubs & balls, tennis rackets, pickleball paddles, hockey sticks). Acoustics & vibration animations & demos.

58 Posts414 Follower174 Folgt
Dan Russell (Dr. Batman)@drussellpsu.bsky.social · 2mo ago

Getting a corner of my research lab setup to start some serious testing of pickleball paddles and balls: modal analysis to measure vibrational mode shapes and frequencies, attempting to correlate with PBCoR, impact sound, noise levels, and other aspects.

experimental setup for modal analysis on a pickleball paddle. A paddle is supported with rubber bands horizontally on a table. A tiny impact hammer tests on the paddle. A laptop computer shows a frequency response function.On the left are two scales with an apparatus for measuring the weight and balance point of a pickleball paddle. On the right is a setup to measure the moment-of-inertia of a paddle, which swings from a pivot at the the handle while a photogate measures the period of the pendulum swinging motion.plot showing the acoustic frequency spectra for the impact of a paddle and ball, with vibrational mode shapes placed above the peaks in the frequency spectrum to show what mode shapes are responsible for what parts of the sound.A pickleball is supported on an impedance head transducer mounted to a vibrational shaker. This apparatus is used to measure the natural frequency of the ball.
Dan Russell (Dr. Batman)@drussellpsu.bsky.social · 4mo ago

New law says I'm a Canadian . . . I was born in the U.S. and my family lived in the US all my life, but my mother was a Canadian citizen (never obtained US citizenship) and my father was a dual citizen of US and Canada. I had a Canadian passport as a child. apnews.com/article/cana...

Millions of Americans may now also be considered Canadian under a new law

Millions more Americans might qualify for dual Canadian citizenship under a recent change to Canada’s requirements that has led to a surge in applications from its southern neighbor.

apnews.com

Dan Russell (Dr. Batman)@drussellpsu.bsky.social · 4mo ago

Fun observation about computer speeds. Figure for my PhD required a 500 term sum evaluated at 1500 frequencies (750,000 calculations). In 1995 my NeXTstation Turbo (33MHz CPU) took 53 hours to generate the plot. Today my 2021 MacBook Pro laptop (Apple M1 chip) did it in 5 minutes.

Alan Nathan@pobguy.bsky.social · 6mo ago

1st results of the Torpedo bat study by Lloyd Smith, @drussell@engr.psu.edu, and me. Measurements done at WSU Sports Science Lab and PSU. Will be presented at ISEA Conference in June. BBCOR, a surrogate for exit velocity, measured for Standard and 2 Torpedo bats via high-speed impact.

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Dan Russell (Dr. Batman)@drussellpsu.bsky.social · 8mo ago

The last several times I have been asked to review manuscripts for a journal, I find myself having to play the role of Reviewer #2 => pointing out fatal flaws, potential plagiarism concerns, incorrect statements, insufficient literature cited. Sigh. I'd like to be Reviewer #1 sometime.

Dan Russell (Dr. Batman)@drussellpsu.bsky.social · 9mo ago

Holy plagiarism, Batman! I just found a 2020 book chapter that plagiarized my data originally submitted (paper copies only!) to the American Journal of Physics in 1998 before the editor asked me to rotate the plots for publication. How did these authors obtain my original unpublished plots?

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Dan Russell (Dr. Batman)@drussellpsu.bsky.social · 12mo ago

I've always been a huge fan of the extensive footnotes in Allan Pierce's "ACOUSTICS" textbook . . . but I've found a new favorite: "Wind Waves" by Blair Kinsman. His writing style is delightfully refreshing for a textbook, but this full-page footnote on the Bernoulli family history is amazing!

scan of two pages from "Wind Waves" by Kinsman showing a full-page footnote that describes several humorous anecdotes about the Bernoulli family history related to mathematics and fluid dynamics theory.
Dan Russell (Dr. Batman)@drussellpsu.bsky.social · 2y ago

What a stupid waste of money. @PSUEngineering is replacing many dozens of doors in our 6 month old new building because the wood veneer on some doors has some unsightly wood knots. Here’s my office door (with ugly knots) that is slated for replacement. What a stupid waste of $$.

Photo of my wood office doorClose up of my office door showing the ugly wood knots that require the door to be replaced.
Dan Russell (Dr. Batman)@drussellpsu.bsky.social · 2y ago

So during a 5-minute "lightning round" #ASA187 session this morning, I complained that someone else's 5-minute talk lasted 12 minutes. Well, this afternoon I contributed to a 5-minute lightning round session. Any guesses as to how long my own "5-minute" talk lasted? 🤦‍♂️🤦‍♀️🤦