
Faculty & Staff
Columbia Engineering Mourns the Death of Longtime Professor Richard W. Longman
Longman was a seminal figure in control theory and an ‘incredible mathematical talent’.
Richard W. Longman, professor of mechanical engineering and professor of civil engineering and engineering mechanics, passed away at his home in the Greater Philadelphia area on October 7, 2024.
Longman, who taught at Columbia Engineering for more than 53 years, was best known for his innovation in the control of dynamic systems, resulting in important contributions to three burgeoning fields: time optimal control of robots for increased productivity, satellite mounted robot kinematics and dynamics, and iterative learning control to make robots doing repetitive tasks improve their performance to ultimately achieve zero tracking error.
“Richard was a seminal figure in control theory, pioneering early incarnations of machine learning in robotics with his introduction of Iterative Learning Control,” says Hod Lipson, James and Sally Scapa Professor of Innovation and chair of the Department of Mechanical Engineering. “He was one of the first people to ask, ‘Why can’t a robot learn from its experience?’”
In 1994, Longman’s research group at NASA Langley Research Center decreased the tracking error of a robot following a high-speed command by a factor of 1,000 in approximately 12 cycles for learning.
The breadth of Longman’s expertise in dynamics and control theory and his genuine curiosity in many different sectors of science and engineering also allowed him to make significant contributions and work closely with various professors from the Department of Civil Engineering and Engineering Mechanics.
“In all these collaborations, Richard brought an incredible mathematical talent, an instinctive understanding of dynamics and an intellectual curiosity and attention to details that were unmatched and that helped raise the bar of all the collaborators,” says Raimondo Betti, professor of civil engineering and engineering mechanics.
In civil engineering, Longman brought an innovative view, based on control theory, to the identification of structural models of bridges and buildings using data recorded at different locations on the structure. Together with Betti and his students in the early 2000’s, Longman was one of the precursors to the introduction of data-based system identification algorithms in civil engineering applications by identifying the modal characteristics of the Vincent Thomas bridge (Los Angeles, CA) through the Observer Kalman filter IDentification (OKID) algorithm, currently used by many researchers worldwide.
“We will greatly miss Richard’s presence on our faculty,” says Dean Shih-Fu Chang. “Richard had only recently retired, but his legacy will continue. He made a real impact in the area of robotics–particularly in Iterative Learning Control and Repetitive Control–contributions that are influencing the field to this day.”
Longman received his BA in physics and in mathematics from the University of California, Riverside in 1965, his MS in aerospace engineering (1967) and his MA in mathematics (1969), as well as a PhD in aerospace engineering from the University of California, San Diego in 1969.
In 1970, Longman joined the faculty of Columbia Engineering in the Department of Mechanical Engineering, and joined the Department of Civil Engineering and Engineering Mechanics in 2003. He was previously a member of the technical staff, Control Systems Research Department at Bell Telephone Laboratories from 1969 to 1970.
Over his career, Longman held visiting positions at many universities and was a Distinguished Romberg Guest Professor at Heidelberg University in Heidelberg, Germany. He consulted or worked for various industries and government laboratories, including NASA Langley Research Center, NASA Goddard Space Flight Center, European Space Operations Center, General Electric Research Labs, Naval Research Labs, Xerox Research Labs, Lockheed Missiles and Space Company, Martin Marietta, and The RAND Corporation. He has also authored more than 400 journal and conference publications. Among his honors, he received the Humboldt Award for Lifetime Research Achievements (Germany), the AAS Dirk Brouwer Award for contributions to Astronautics, and a Proctor and Gamble Publication Award. He was a Fellow of the American Institute of Aeronautics and Astronautics (AIAA) and the American Astronomical Society (AAS).
In addition to his research, Longman was also a photographer specializing in art and dance photography. His photos have been exhibited all over the world and his work is in the permanent collection at the Museum of Central Bohemia in Prague, Czech Republic.