2 research outputs found
Observer-based adaptive emotional controller for a class of uncertain nonlinear systems
Uncertainties and complexities of the actual control problems, such as unknown dynamics, unmeasurable states, external disturbances, and measurement noise, require powerful control structures capable of handling such complexities. Emotional controllers offer fast system response while also carrying a simple structure. However, the emotional controllers to date have not been evaluated rigorously. Here, the continuous radial basis emotional neural network (CRBENN) is employed to approximate the unknown dynamics in observer-based adaptive control structures for uncertain affine nonlinear systems. The system dynamics are unknown. Also, external disturbance and measurement noise affect system performance. Compared to the previous emotional controllers, the system states are not measurable and are estimated using a state estimator. The H∞ tracking performance is verified using Lyapunov stability theory, and suitable adaptive laws are designed for the weights of the proposed emotional networks that are consistent with the basic brain emotional learning model. Results indicate that the proposed controllers reach a lower tracking error with similar control energy consumption compared to another neuro-controller
PAC: A Novel Self-Adaptive Neuro-Fuzzy Controller for Micro Aerial Vehicles
There exists an increasing demand for a flexible and computationally
efficient controller for micro aerial vehicles (MAVs) due to a high degree of
environmental perturbations. In this work, an evolving neuro-fuzzy controller,
namely Parsimonious Controller (PAC) is proposed. It features fewer network
parameters than conventional approaches due to the absence of rule premise
parameters. PAC is built upon a recently developed evolving neuro-fuzzy system
known as parsimonious learning machine (PALM) and adopts new rule growing and
pruning modules derived from the approximation of bias and variance. These rule
adaptation methods have no reliance on user-defined thresholds, thereby
increasing the PAC's autonomy for real-time deployment. PAC adapts the
consequent parameters with the sliding mode control (SMC) theory in the
single-pass fashion. The boundedness and convergence of the closed-loop control
system's tracking error and the controller's consequent parameters are
confirmed by utilizing the LaSalle-Yoshizawa theorem. Lastly, the controller's
efficacy is evaluated by observing various trajectory tracking performance from
a bio-inspired flapping-wing micro aerial vehicle (BI-FWMAV) and a rotary wing
micro aerial vehicle called hexacopter. Furthermore, it is compared to three
distinctive controllers. Our PAC outperforms the linear PID controller and
feed-forward neural network (FFNN) based nonlinear adaptive controller.
Compared to its predecessor, G-controller, the tracking accuracy is comparable,
but the PAC incurs significantly fewer parameters to attain similar or better
performance than the G-controller.Comment: This paper has been accepted for publication in Information Science
Journal 201