Michael Littman enlisted the help of children

In celebration of the 25th anniversary of his course on microprocessors, Michael Littman treated the young and the young at heart to a mini-tutorial in train signal processing at the 2006 Princeton Reunions.

In attendance at the event were Richard Wotiz and Virginia Blaha Lamere, both of the class of 1981, whom Littman, a professor of mechanical and aerospace engineering at Princeton, credited with reverse-engineering the protocol of the digital system used to run the Hornby model train system used in the course.

Richard Wotiz (right) and Virginia Blaha Lamere (center)

Richard Wotiz (right) and Virginia Blaha Lamere (center), mechanical and aerospace majors from the class of 1981, look on as Littman explains how their work contributed to his class on microprocessors.

“Based on that knowledge we were able to build the course,” said Littman.

Littman and technical staff member David Radcliff enlisted the help of children in the audience to physically demonstrate how railway “block controls” work. “Basically, we’re talking about traffic signals for railroads,” Littman said.

In the actual undergraduate course MAE 412, “Microprocessors for Measurement and Control,” Princeton students automate a model railroad using microcomputers that they design, build and program. The model trains are controlled with optical, magnetic, and electromechanical sensors and actuators.

At his reunions demonstration, Littman presented a timeline of some of the alumni who contributed to the structure of the course. He also showed video clips from the last five years’ worth of final projects.

Littman, Wotiz and Blaha wrote an article for Model Railway Electronics in 1984 describing an early example of how “microprocessors may be used effectively for performing complex tasks using electromechanical devices.

Students watching demostration

A Timeline of MAE 412 milestones:

W. Radigan (MAE Tech) suggests that students build their own single-board microcomputer
Richard Wotiz ’81 and Virginia Blaha ’81 figure out HORNBY data protocol
John H. Gurian ’83 and David A. Simon ’83 write program that allows HORNBY Network Controller commands to be understood by individual microcomputers
Philip B. Dworsky ’83 designs circuit that allows a host computer to remotely operate the HORNBY Network Controller
John E. (Ned) Lecky ’84 and Howard A. Fiderer ’82 add automatic block control and locomotive identification via bar-codes
Michael J. Arena ’86 and Arthur L. (Tad) Coburn ’87 improve HORNBY Network Controller allowing for two-way communication between host computer and block computers
Gordon D. Bitko ’91, John Y. Chang ’91, and Daniel C. Lockwood ’89 assist with design and construction of the Franklin Institute Railroad Hall Exhibit (1989 – 1996)
David Radcliff (MAE Tech) adds reversing loops to test-stands, re-organizes the teaching laboratory, introduces rapid prototyping of printed circuit boards


  • Michael Littman

Related Department

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    Mechanical and Aerospace Engineering