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Dan Russell (Dr. Batman) @drussellpsu.bsky.social · 06/08/2026

Another teaser trailer for the ACS 537 Noise Control Engineering course I'm also teaching this Fall 2026 both for resident students and online. This course counts toward the Noise Control Certificate through the Penn State World Campus. @psuengineering.bsky.social youtu.be/k_IMQtX7foc

youtu.be

ACS 537 Noise Control Engineering Fall 2026

YouTube video by Dan Russell

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Dan Russell (Dr. Batman) @drussellpsu.bsky.social · 06/08/2026

Approaching the Fall 2026 semester . . . my 16th year of teaching Acoustics to graduate students at Penn State (my 32nd year of university teaching overall). It's time for another movie trailer for one of courses I'll be teaching. youtu.be/pcuuuigtCc0 @psuengineering.bsky.social #iteachphysics

youtu.be

ACS 502 Sound Waves in Fluids Fall 2026

YouTube video by Dan Russell

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Dan Russell (Dr. Batman) @drussellpsu.bsky.social · 28/07/2026

I'm on the cover of a Magazine!!! My paper "An educational opportunity: Acoustics in an empty room" is featured on the front cover of the July 2026 issue of the Journal of the Acoustical Society of America. doi.org/10.1121/10.0...

Mike Wozowski from Monsters Inc. opens a box and declares "I'm on the cover of a mazagine!"

cover image for the July 2026 issue of the Journal of the Acoustical Society of America, showing standing wave modes (white for nodal surfaces, blue and red for oppositely phased maxima) in an empty room.

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Dan Russell (Dr. Batman) @drussellpsu.bsky.social · 30/06/2026

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.

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Dan Russell (Dr. Batman) @drussellpsu.bsky.social · 15/05/2026

Acoustical Society of America 2025 Rossing Prize for Acoustics Education.

Acoustical Society of America Rossing Prize for Acoustics Education

Dr. Dan Russell delivering the Rossing Prize Lecture.

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Reposted by Dan Russell (Dr. Batman)

Acoustical Society of America @asa-news.bsky.social · 13/05/2026

How Effective Are Torpedo Bats, Exactly? - Acoustic analysis can reveal the benefits of baseball’s newest invention. wp.me/paqHd5-57O #ASA190 Image Credit: Dan Russell

Man in a plaid shirt working on an experiment setup with a baseball bat in a cluttered lab.

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Dan Russell (Dr. Batman) @drussellpsu.bsky.social · 02/05/2026

My 2013 27-inch iMac died and it couldn’t go beyond Mac OS 10.15 Catalina. Just got a new MacBook Air (M5) with external monitor and OS 26.4 Tahoe. Of course I had to make sure I could still play Doom (runs great!)

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Dan Russell (Dr. Batman) @drussellpsu.bsky.social · 27/04/2026

and my brand new 2026 MacBookAir (Apple M5 chip) ran the code in just over 3 minutes.

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Dan Russell (Dr. Batman) @drussellpsu.bsky.social · 24/04/2026

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...

apnews.com

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.

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Dan Russell (Dr. Batman) @drussellpsu.bsky.social · 21/04/2026

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.

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Dan Russell (Dr. Batman) @drussellpsu.bsky.social · 13/04/2026

Saw this quote from J.R.R. Tolkien posted somewhere a while ago . . . for the last 15 years as a Teaching Professor of Acoustics in the Graduate Program in Acoustics at Penn State, this has been true for me also.

photo of J.R.R. Tolkien at his desk . . . with the quote ". . . I was never obliged to teach anything except what I loved (and do) with an inextinguishable enthusiasm." -- J.R.R. Tolkien, Letter 250

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Dan Russell (Dr. Batman) @drussellpsu.bsky.social · 12/04/2026

Yup. I have a couple of things for that space that I just haven’t hung yet. 🤣

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Dan Russell (Dr. Batman) @drussellpsu.bsky.social · 12/04/2026

My campus office when I moved in (summer 2024) and now (spring 2026)

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Dan Russell (Dr. Batman) @drussellpsu.bsky.social · 08/04/2026

Second bending mode for a free-free bar

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Dan Russell (Dr. Batman) @drussellpsu.bsky.social · 08/04/2026

First bending mode for a free-free bar

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Dan Russell (Dr. Batman) @drussellpsu.bsky.social · 08/04/2026

I have a new M.S. student working with me - exploring vibroacoustic behavior of ping-pong paddles (including the new 7-sided STIGA Cybershape). He's learning how to do experimental modal analysis - some of the cleanest free-free bar data I've seen a new student collect. #iTeachPhysics

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Dan Russell (Dr. Batman) @drussellpsu.bsky.social · 20/03/2026

One of my graduate students is making a website with some useful interactive tools for teaching acoustics concepts . . . today in my undergrad Intro to Acoustics class, I used his online web-based spectrogram for a demonstration. What a useful tool! www.acs.psu.edu/noahparker/a...

Dan Russell pointing to a spectogram, explaining how the lines in the spectrogram represent the frequency content of my voice.

Dan Russell (with spectrogram in the background) explaining how the frequency content of my voice changes after filling my lungs (and vocal tract) with helium instead of air.

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Reposted by Dan Russell (Dr. Batman)

Alan Nathan @pobguy.bsky.social · 21/02/2026

Better plot:

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Reposted by Dan Russell (Dr. Batman)

Alan Nathan @pobguy.bsky.social · 21/02/2026

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 · 19/12/2025

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.

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Dan Russell (Dr. Batman) @drussellpsu.bsky.social · 05/12/2025

Robert Keolian's apparatus for demonstrating how the Basilar membrane works - the von Békésy "place theory of hearing". Robert M. Keolian, "A demonstration apparatus of the cochlea," J. Acoust. Soc. Am., 101, 1199–1201 (1997). youtu.be/MV-XbzLPijA?...

youtu.be

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Dan Russell (Dr. Batman) @drussellpsu.bsky.social · 26/11/2025

Now that the U.S. is no longer making the 1-cent penny coin, I was reminded of these 1-cent paper bills we used to use in Hong Kong in the 1970’s.

Paper 1-cent bill from Hong Kong in the 1970’s

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Dan Russell (Dr. Batman) @drussellpsu.bsky.social · 19/11/2025

I contacted Beth. AJP doesn't have paper records from 1998, and double blind review process prevents identifying reviewers. My LinkedIn post made its way to the 2nd author faculty advisor of student who plagiarized my work. He emailed me to apologize. Still don't know how they got those plots.

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Dan Russell (Dr. Batman) @drussellpsu.bsky.social · 15/11/2025

That's the only explanation I can think of. Back in 1998, there was no electronic submission. I mailed 4 paper copies to editor, who kept one and sent 3 out for review. I'm guessing one of the reviewers kept a copy? Was this author a reviewer? (unlikely), but perhaps saw a copy the reviewer had?

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Dan Russell (Dr. Batman) @drussellpsu.bsky.social · 14/11/2025

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 · 04/09/2025

Agreed. I also really prefer white for ambient. I wonder if BuVe is available as a color map option in the current version of Mathematica? I have tried a Pink-White-Green colormap that also seems to work for most color-blind cases: www.acs.psu.edu/drussell/Dem... (see the comparison at the bottom)

acs.psu.edu

Rectangular Membranes

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Dan Russell (Dr. Batman) @drussellpsu.bsky.social · 04/09/2025

I need to spend more time here on your 🦋 pages looking through your new animations. These look really useful. I really hope you are able to gather your all amazing animations together on a website someday.

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Dan Russell (Dr. Batman) @drussellpsu.bsky.social · 04/09/2025

yes. I've started using a similar "cividis" color map for many of my animations for similar color-blind accessibility reasons -- but haven't had time to go back and re-create all of my animations that use RWB yet.

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Dan Russell (Dr. Batman) @drussellpsu.bsky.social · 04/09/2025

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.

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Dan Russell (Dr. Batman) @drussellpsu.bsky.social · 04/09/2025

Those are awesome! I did the same thing (showing the oscillation paths and elliptical motion) for a couple of "particles" in the animations I created for my website in 2014: www.acs.psu.edu/drussell/Dem... I really like the RWB coloring addition to the "Sparrowgram" particle motion on yours.

acs.psu.edu

Evanescent Waves & Radiation from a Plate

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Dan Russell (Dr. Batman) @drussellpsu.bsky.social · 31/07/2025

Time for another fun movie trailer to entice interest in the first-year graduate course in Acoustics that I'll be teaching for the Graduate Program in Acoustics at Penn State in the Fall 2025 semester. Simultaneously offered online through our distance education program! youtu.be/fKPA5HL76Ps?...

youtu.be

ACS 502 Sound Waves In Fluids Fall 2025 at Penn State

YouTube video by Dan Russell

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Dan Russell (Dr. Batman) @drussellpsu.bsky.social · 29/07/2025

30 years of making animations . . . I'm updating HTML code for my Acoustics and Vibration Animations website (for WCAG accessibility and HTML5) and found an archive of my original website from 25 years ago with a photo of me in my office at Kettering University. www.acs.psu.edu/drussell/demos.html

photo of Dan Russell (white male, approximately 30 years old, blond hair and glasses, wearing a red shirt) sitting to the right of a computer monitor.

photo of Dan Russell (white male, approximately 55 years old, gray hair, beard, and glasses, wearing a checkered shirt) standing to the left of a computer monitor.

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Dan Russell (Dr. Batman) @drussellpsu.bsky.social · 24/04/2025

Thanks! I learned that technique from Tom Rossing in 1990 while I was working on my MS with him.

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Dan Russell (Dr. Batman) @drussellpsu.bsky.social · 23/04/2025

Brand new video demonstration . . . Standing Waves inside a Cylindrical Cavity. Finding nodal surfaces for acoustic standing wave mode shapes inside a cylinder with "rigid" walls -- a plastic CD container. #iteachphysics #acoustics youtu.be/-4IqtGhWe2U?... via @YouTube

youtu.be

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Dan Russell (Dr. Batman) @drussellpsu.bsky.social · 09/04/2025

Except that this thesis explored computer models of hollow aluminum bats that were rigidly clamped at the handle which is completely wrong. So the results of her models are pretty much useless for predicting handle vibration in actual bats or sweet spot location.

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Dan Russell (Dr. Batman) @drussellpsu.bsky.social · 09/04/2025

Really good preliminary summary of what we know so far about torpedo bats by my fellow bat researcher @pobguy.bsky.social blogs.fangraphs.com/the-physics-...

blogs.fangraphs.com

The Physics of the Torpedo Bat

What can physics tell us about the torpedo bats?

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Dan Russell (Dr. Batman) @drussellpsu.bsky.social · 10/03/2025

My favorite way to spend a quiet Sunday evening.

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Dan Russell (Dr. Batman) @drussellpsu.bsky.social · 18/02/2025

How can a person with “zero education” ever learn to ask the right questions? Education in the relevant field is what helps you know the right questions to ask.

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Dan Russell (Dr. Batman) @drussellpsu.bsky.social · 19/12/2024

Don’t know. I’m a non-tenure track teaching faculty so I don’t have overhead return. Turns out the architect firm demanded the doors be replace and the contracted supplied is eating the cost. Still seems like an awful waste to me. Doors are going to be discarded to trash.

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Dan Russell (Dr. Batman) @drussellpsu.bsky.social · 17/12/2024

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 $$.

Close up of my office door showing the ugly wood knots that require the door to be replaced.

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Dan Russell (Dr. Batman) @drussellpsu.bsky.social · 23/11/2024

Where did you get that amazing birdfeeder pole?

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Dan Russell (Dr. Batman) @drussellpsu.bsky.social · 21/11/2024

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? 🤦‍♂️🤦‍♀️🤦

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Dan Russell (Dr. Batman) @drussellpsu.bsky.social · 21/11/2024

Thank you for letting me know you find them useful!

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Dan Russell (Dr. Batman) @drussellpsu.bsky.social · 20/11/2024

Listening to the keynote address for #ASA187 . . . humorous inverse correlation => larger larynx (deeper + louder vocal production) in howler monkeys correlates to smaller testicles. Bigger balls means less powerful and higher sounding howl.

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