Remembering Robert Errichello

The gear industry has lost one of its most respected figures. Robert Errichello, founder of GEARTECH and a leading authority on gear design, failure analysis, and tribology, has passed away. He was 84. Over a career spanning more than 57 years, Bob made contributions to gear engineering and standards development that will endure for generations.

Bob published more than 80 articles on the design, analysis, and application of gears, authored three widely used computer programs for gear design and analysis, and consulted for more than 50 wind turbine manufacturers, purchasers, operators, and researchers. He taught courses in material science, fracture mechanics, vibration, and machine design at San Francisco State University and the University of California at Berkeley, and presented numerous seminars to professional societies and the gear, bearing, and lubrication industries. He served as technical editor for both Gear Technology and STLE’s Tribology Transactions. A graduate of the University of California at Berkeley, he held BS and MS degrees in mechanical engineering and a Master of Engineering degree in structural dynamics. His contributions were recognized with the AGMA TDEC Award, the AGMA E.P. Connell Award, the AGMA Lifetime Achievement Award, the STLE Wilbur Deutch Memorial Award, the 2015 STLE Edmond E. Bisson Award, and the AWEA Technical Achievement Award.

But the vitae only hints at what made Bob exceptional. He was one of the people doing the foundational technical work that informed AGMA standards, producing dozens of original reports on gear rating, metallurgy, tribology, and nomenclature—not summaries or opinion pieces, but original derivations and analyses that directly supported the standards development process. His work on AGMA 925 alone comprised 23 reports over seven years, methodically addressing gear tribology from elastohydrodynamic lubrication theory to scuffing prediction. Many went through multiple revisions, reflecting his insistence on getting every detail right.

“Bob Errichello was a powerhouse within the gearing technical community for 50+ years,” noted Jason Daubert, MPMA’s Technical Division Executive Committee Chair and Chief Engineer at Fuller. “In 2025 alone, he participated in 54 technical committee calls across 14 technical committees and working groups, providing complex data and sage engineering guidance across a wide range of topics. His mind was truly amazing, and AGMA standards strongly benefited from his support.”

For 27 years, Bob and Jane Muller taught the AGMA Gear Failure Analysis seminar, which became AGMA’s most popular course. In 2016, he separately gave his Gear Failure Analysis course to MPMA, where it has also become their most popular offering. “His legacy will live on through Gear Failure Analysis, MPMA’s most popular class—one Bob gave to MPMA in 2016, and that has since benefited thousands of engineers,” said Sara Zimmerman, MPMA Chair and Vice President CX and Product at Sumitomo. “On behalf of the Board of Directors, our sincerest condolences to Jane and the Errichello family and friends for this tremendous loss.”

“Bob was great to work with, and I was fortunate to work with him as a colleague and attend his Gear Failure class when I was with Cotta and as a technical contributor with MPMA,” noted Todd Praneis, Vice President, Technical Services at MPMA. “His passion was contagious and he was a fierce advocate for the science of our craft, requiring everyone to be on their A-game when forming standards. We will miss him terribly.”

Frank C. Uherek, Principal Engineer at Regal Rexnord and a longtime AGMA colleague, pointed to several of Bob’s defining technical contributions. Among them was his development of a calculation method for the geometry factor used in bending-strength power capacity, which eliminated the labor-intensive practice of hand-drawing large-scale tooth-root fillets and made it possible to compute the factor accurately by computer. Bob also played a major role in creating the first AGMA information sheet for wind-energy gearboxes—work that ultimately led to an AGMA rating standard and became a major source of technical content for the ISO/IEC joint wind-turbine standard published this year. “Bob was unwavering in his belief that gear rating practices must be grounded in sound science rather than approximations or extrapolations from limited test data,” Uherek noted. He added that Bob’s insistence that every technical term have a single, authoritative definition shaped AGMA 1012, Gear Nomenclature, and AGMA 1010, the gear failure classification documents. “Thanks to his efforts, gear engineers can communicate with clarity and precision — speaking the same technical language across the industry.”

Fellow Gear Technology technical editor Chuck Schultz first met Bob at an AGMA committee meeting in 1979. “He was a leader in modernizing the gear rating method, taking it away from pages of charts and into formulas that could be written into computer programs,” Schultz recalled. “When Bob started publishing commercial software, I bought a very low serial number and stopped writing my own code. Over the years our paths crossed frequently. When I started consulting in 2008, Bob helped me find clients. He and Jane were instrumental in AGMA being world leaders in wind turbine gear design standards.” Schultz noted that quality engineers sometimes conduct “best of the best” studies to identify influence factors on product performance. “Bob, in my mind, was the best of the best in the gear engineering trade. There will never be another like him.”

The thousands of engineers who learned failure analysis through his courses, the standards that bear his contributions, and the pages of this magazine that carry his name—these are what Bob leaves behind. On behalf of the entire staff of Gear Technology and Power Transmission Engineering, we extend our deepest condolences to Jane and the Errichello family. Rest in peace, Bob.