Patents, software, and hardware for PID control: an overview and analysis of the current art

The wide application of proportional-integral-derivative (PID) control has stimulated and sustained the development and patenting of various tuning and associated system identification techniques. However, to achieve optimal transient performance, tuning methods vary, and at present there exists no standardization of PID structures. This article provides an overview and analysis of PID patents, commercial software packages, and hardware modules. It also highlights the differences between academic research and industrial practice so as to motivate new research directions in PID technology.