Modelling, simulation and implementation of a hybrid model reference adaptive controller applied to a manipulator driven by pneumatic artificial muscles

Abstract

The present research aims to model, simulate and implement a new hybrid control approach based on a combination of proportional integral derivative (PID) Controller and Model Reference Adaptive Controller (MRAC), in which Lyapunov’s theory is used to ensure asymptotic stability to control a two degrees of freedom (DoF) manipulator driven by McKibben’s artificial pneumatic muscles. The MRAC controller works as a nonlinearity compensator and PID controller works during the transient period, as the MRAC performs poorly in this regime. This new approach is entitled Hybrid Model Reference Adaptive Controller (H-MRAC) and it has an unprecedented topological structure based on three terms. The feedforward term acts in disturbances rejection, the derivative term in oscillations damping and the feedback term acts in error convergence to zero. In this article, a control system dedicated to pneumatic manipulators was developed. As a result, proof of asymptotic convergence was performed for the proposed topological approach, which was validated on a two DoF manipulator. The proposed mechanism satisfactorily met the ISO/TS 15066 standard, and the position tracking obtained a global error of 37.69% and 51.01% smaller than found in the literature examples, entitled MRAC and A-PID, respectively, for simulations and 37.46% and 30.25% for experiments.

Design, analysis and experiment of robust adaptive repetitive angle tracking control for a one-DOF manipulator driven by pneumatic artificial muscles

“…Theorem 1: Considering the PAM-driven one-DOF manipulator (17) under Assumption 1, RARC law ( 29)- (31) and repetitive learning laws (32)-( 35), the closed-loop one-DOF manipulator system can be stabilized in the sense that lim t! + ' e(t) = 0, and the output error is constrained in the preset time-varying bound during system operation.…”

“…In Zhao et al, 15,16 nonlinear extended state observers are used to estimate total disturbance in single-joint manipulator and double-joint manipulator systems driven by PAMs, respectively. In Bomfim et al, 17 a hybrid model reference adaptive controller is designed for a two DOF manipulator driven by PAMs. These above-mentioned methods can improve the control performance of PAM-driven manipulator systems from different aspects.…”

Design and validation of a novel adaptive motion control for a pendulum spherical robot

“…For example, Roozegar M. et al [31] developed an MRAC-based adaptive method for the control of pendulum-driven SRs. Bomfim M. et al [32] designed a Lyapunov-based hybrid MRAC for a pneumatic artificial muscle-actuated manipulator. Inspired by the above research, a Lyapunov-based MRAC control algorithm is proposed.…”