iiinova — where your digital self keeps evolving

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

020

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

080

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.

093

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.

040

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.

140

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.

041

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!)

010

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.

110

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.

250

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

030

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

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

190

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

140

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.

3134

Reposted by Dan Russell (Dr. Batman)

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

Better plot:

021

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.

152

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.

040

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

051

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

020

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?

150

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.

082

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

293

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.

030

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

2143

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?

040

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

My favorite way to spend a quiet Sunday evening.

130

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.

320

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? 🤦‍♂️🤦‍♀️🤦

030

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.

050

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

Audio/Video demonstration of an "acoustic thermometer" => how the speed of sound changes with temperature — observed as a change in the resonance frequency of a short closed-open pipe. youtu.be/9Pmsn_JZU-4 #iTeachPhysics

youtu.be

Speed of Sound Depends on Air Temperature

YouTube video by Dan Russell

2162

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

During the current migration to 🦋 I have gained lots of new #iTeachPhysics follows including many people I don’t recognize from X. I currently teach grad level acoustics but my waves and vibration animations website is useful for HS and undergrads students: www.acs.psu.edu/drussell/demos.html

acs.psu.edu

Dan Russell's Acoustics and Vibration Animations

4233

Dan Russell (Dr. Batman) @drussellpsu.bsky.social · 19/11/2024

just heard a cool presentation at the ASA 187 Virtual Meeting . . . taking each element in the periodic table and creating an audible sound based on the atomic emission/absorption spectrum for that element. academics.skidmore.edu/blogs/jlinz/

academics.skidmore.edu

Jill Linz

173

Dan Russell (Dr. Batman) @drussellpsu.bsky.social · 02/08/2023

1/2 Next year my graduate program is moving into a new building (currently under construction). My office will be smaller and I've been told I have to downsize from 4 completely full bookshelves to 2 (yikes!). So, I made a first pass thru my office library to identify books . . .

120

Dan Russell (Dr. Batman) @drussellpsu.bsky.social · 30/07/2023

Went through some of my parents’ photos after dad died last year and found this autographed photo of Tenzig Norgay (2nd person to the top of Mt Everest in 1953 behind Sir Edmund Hillary). I got this photo as a kid in Hong Kong in 1976 but thought it was lost years ago. Wonder if it’s worth any $$?

080