John Ziegler, founder of Ziegler & Associates, was one of the pioneers in the measurement and control field. Working with
the late mathematician Nathaniel Nichols at Taylor Instruments in the early 1940s, he conceived
the now famous method of tuning proportional-integral-derivative (PID) controllers. While there
was P control and I control at the time, PID control was new. Moreover, none of the methods had
a hard set of rules for tuning, relying on touch, feel and 'seat-of-the-pants' settings.
Ziegler had the process application experience and performed the simulator testing that led to the results they sought, while Nichols reduced the mechanical manipulations to a few mathematical relationships that could be understood by technicians and operators. Their findings, presented to the American Society of Mechanical Engineers in 1941, were criticized by many at the time as blasphemy. However, the Ziegler-Nichols rules survived and are still in use as the next millennium approaches.
In the 1980s Ziegler lectured on methods to maximize yeilds and solved mechanical and technical problems at ailing facilities. Below are some of his insightful writings on the sugar industry.
Articles by John Ziegler
- Sugar Boiling: Some Facts and Some Fancies
- Sugar Boiling: Some Useful Strategies
- Sugar Boiling: The Syrups in Vacuum Pans