Enhanced Position Control for Pneumatic System by Applying Constraints in MPC Algorithm

This paper demonstrates the effectiveness of applying constraints in a controller algorithm as a strategy to enhance the pneumatic actuator system’s positioning performance. The aim of the present study is to reduce the overshoot in the pneumatic actuator positioning system’s response. An autoregressive with exogenous input (ARX) model structure has been used to model the pneumatic system, while a model predictive control (MPC) has been employed as a control strategy. The input constraint has been applied to the control signals (on/off valves signals) to ensure accurate position tracking. Results show that the strategy with constraint effectively reduced overshoot by more than 99.0837 % and 97.0596 % in simulation and real-time experiments, respectively. Moreover, the performance of the proposed strategy in controlling the pneumatic positioning system is considered good enough under various loads. The proposed strategy can be applied in any industry that used pneumatic actuator in their applications, especially in industries that involved with position control such as in manufacturing, automation and robotics. The strategy proved to be capable of controlling the pneumatic system better, especially in the real-time environment

Robust Control Strategy for Pneumatic Drive System via Enhanced Nonlinear PID Controller

This paper presents the pneumatic positioning system controlled by Enhanced Nonlinear PID (NPID) controller. The characteristic of rate variation of the nonlinear gain that are readily available in NPID controller is utilized to improve the performance of the controller. A Self-regulation Nonlinear Function (SNF) is used to reprocess the error signals with the purpose of continuously generating the values for the rate variation. Subsequently, the controller has successfully been implemented on dynamically changing loads and pressures. The comparison with the other available method such as. NPID and conventional PID are performed and evaluated.  The effectiveness of this method with Dead Zone Compensator (DZC) has also been successfully demonstrated and proven through simulations and experimental studies.DOI:http://dx.doi.org/10.11591/ijece.v4i5.685

Practical robust control using Self-regulation Nonlinear PID controller for pneumatic positioning system

This paper investigates the robustness of the pneumatic positioning system controlled by Self-regulation Nonlinear PID (SNPID) controller. This controller is executed by utilizing the characteristic of rate variation of the nonlinear gain that are readily available in Nonlinear PID (NPID) controller. A Self-regulation Nonlinear Function (SNF) is used to reprocess the error signal with the purpose to generate the value of the rate variation, continuously. Simulation and experimental tests are conducted. The controller is implemented to a variably loads and pressures. The comparison with the other existing method i.e. NPID and conventional PID are performed and evaluated. The effectiveness of SNPID + Dead Zone Compensator (DZC) has been successfully demonstrated and proved through simulation and experimental studie

Position control of pneumatic actuator using an enhancement of NPID controller based on the characteristic of rate variation nonlinear gain

This paper presents an enhancement of nonlinear proportional-integral-derivative (PID) controller for pneumatic positioning system by utilizing the characteristic of rate variation nonlinear gain known as multi-rate nonlinear PID controller. The proposed technique is designed and implemented to a variably loaded pneumatic actuator. To utilize the rate variation of nonlinear gain, fuzzy logic technique was used in determining the appropriate rate selection to produce a rapid response without generating a significant overshoot. Simulation and experimental tests are conducted with different kinds of input, namely, step, sinusoidal, and random wave forms to evaluate the performance of the proposed technique. The results have proven as a novel initiative at examining and identifying the characteristic based on a new proposal controller resulting from NPID controller where the transient response has improved by a factor of 7 times greater than the previous NPID technique. Moreover, the performance of pneumatic positioning system is remarkably good when operated under the variable load condition

Identification and self-tuning control of electro-pneumatic actuator system with control valve

In this paper, a mathematical modeling of pneumatic actuator system is developed by using RLS algorithm. An ARX model is chosen for the model structure. In order to cater the time-varying parameter of pneumatic system, a self-tuning controller is implemented based on the pole-assignment controller. An online RLS algorithm update the parameter estimation at every sample interval. The pole-assignment control parameter is then updated accordingly to the changes of the system parameters. Result of the system performance is compared with the conventional PID controller optimized by PSO algorithm. It is observed that the self-tuning controller performed well with almost zero error at steady state condition and overshoot less than 1%

Non-linear modeling and cascade control of an industrial pneumatic actuator system

In this paper, a nonlinear mathematical modeling based on fundamental physical derivation is presented. The mass flow rate, pressure dynamic and equation of motion are derived referring to the previous research. Simulation work is done to confirm the model based on this derivation. Cascade control based on PID and P controller is designed through simulation in SIMULINK where the parameters of the controller are obtained through PID with optimization toolbox. The results reveal that both step and sinusoidal response test, the cascade controller consistently indicates outperform performance compared to classical PID method. In future, it is recommended to apply this technique to the real-time implementation