A Fully Mechanical Realization of PID Controller

Abstract

PID controller is one of the most widely used control elements in the industry. Over history, people have implemented the PID controller mechanically with pneumatical components, electronically in circuits, or digitally using DSP. However, the pure mechanical realization of PID controllers is rarely studied. This paper presents an analog PID controller based on mechanical computation components, including a mechanical integrator, a mechanical differentiator, mechanical constant multipliers, and a mechanical adder. In this work, those parts are studied respectively with CAE modeling and mathematical derivation. A novel design of mechanical differentiator is also introduced to conduct the calculation of the differential part on the PID controller. This work explores the theoretical possibility of a new form of PID controller realization, that is, applying the method of mechanical analog computation to the implementation of a PID controller.