Position Control of a Pneumatic Drive Using a Fuzzy Controller with an Analytic Activation Function

The fuzzy logic controller, which uses an analytic activation function for the defuzzification procedure, was applied to the position control of a servo pneumatic drive controlled by a proportional valve. The Gaussian shape of input fuzzy sets, with the possibility of their modification, was used to fuzzify the input signal. The control signal was determined by introducing an analytic function instead of defining the fuzzy rule base. In this way, a conventional 2-D fuzzy rule table base is modified into 1-D fuzzy defuzzification based on an analytic function to calculate the controller output. In this control algorithm, the problem of conventional fuzzy logic control, in terms of the exponential growth in rules as the number of input variables increases, is eliminated. The synthesis controller procedure is adjusted to the flow rate characteristic of the proportional valve. The developed control algorithms are verified by computer simulation and by testing on a real pneumatic rodless cylindrical drive.

Automated summary

This paper presents a method for position control using a fuzzy logic controller. By using an analytic activation function, modifying the Gaussian shape of the fuzzy sets, and introducing an analytic function to determine the control signal, the problem of exponential growth in rules in conventional fuzzy logic control is addressed. The control algorithm is adjusted based on the flow rate characteristic of the proportional valve, and its effectiveness is verified through computer simulation and experimental testing on a real pneumatic rodless cylindrical drive.