Professor Vadim I. Utkin, formerly Ford-chair Professor of Ohio State University, passed away on September 18, 2022, in a Columbus hospital, Ohio. He was 84 years old, 12 days toward his 85th anniversary.

Vadim Utkin was born in Moscow, Russia, on September 30, 1937. He graduated from Moscow Power Institute (Dipl. Eng.), received Ph.D. and Doctor of Sciences degrees from Institute of Control Sciences (Moscow, Russia). With the latter Institute, he was in 1960–1994, since 1973 as Head of the Discontinuous Control Systems Laboratory.

Prof Utkin was an author and co-author of six books and more than 350 papers. Recognitions and honors he received for his groundbreaking scientific contribution include the Lenin Prize in the former USSR and Oldenburger medal from ASME. He was an IEEE fellow.

Vadim Utkin was one of the originators of the concept of Variable Structure Systems and he pioneered Sliding Mode Control area with application interests in control of power converters and electric drives, robotics, and automotive control. He initiated sliding mode researches with his numerous master and PhD students, and co-workers from different countries. Inspired by the innovative ideas he generously shared, numerous scientific schools in many countries such as Russia, USA, Mexico, Italy, Japan, France, UK, and Brazil to name a few continue to creatively develop the sliding mode approach.

On the human side, he was unique, exceptionally engaging, insightful, witty, with an intelligent irony, energetic yet gentle in his criticism, and always the center of attention in any group, whether technical or social.

Revolutionary ideas, generated by Professor Utkin, will continue to influence his followers, and his bright image will live in us.