Control of magnetic levitation system using recurrent neural network-based adaptive optimal backstepping strategy

2020 ◽  
Vol 42 (13) ◽  
pp. 2382-2395
Author(s):  
Armita Fatemimoghadam ◽  
Hamid Toshani ◽  
Mohammad Manthouri
Keyword(s):  
Neural Network ◽  
Recurrent Neural Network ◽  
Optimization Problem ◽  
Closed Loop ◽  
Magnetic Levitation ◽  
Backstepping Control ◽  
Loop System ◽  
Closed Loop System ◽  
Levitation System ◽  
Magnetic Levitation System

In this paper, a novel approach is proposed for adjusting the position of a magnetic levitation system using projection recurrent neural network-based adaptive backstepping control (PRNN-ABC). The principles of designing magnetic levitation systems have widespread applications in the industry, including in the production of magnetic bearings and in maglev trains. Levitating a ball in space is carried out via the surrounding attracting or repelling magnetic forces. In such systems, the permissible range of the actuator is significant, especially in practical applications. In the proposed scheme, the procedure of designing the backstepping control laws based on the nonlinear state-space model is carried out first. Then, a constrained optimization problem is formed by defining a performance index and taking into account the control limits. To formulate the recurrent neural network (RNN), the optimization problem is first converted into a constrained quadratic programming (QP). Then, the dynamic model of the RNN is derived based on the Karush-Kuhn-Tucker (KKT) optimization conditions and the variational inequality theory. The convergence analysis of the neural network and the stability analysis of the closed-loop system are performed using the Lyapunov stability theory. The performance of the closed-loop system is assessed with respect to tracking error and control feasibility.

Backstepping Based Adaptive Control of Magnetic Levitation System

2013 ◽  
Vol 341-342 ◽  
pp. 945-948 ◽  
Author(s):  
Wei Zhou ◽  
Bao Bin Liu
Keyword(s):  
Parameter Uncertainty ◽  
Closed Loop ◽  
Controller Design ◽  
Magnetic Levitation ◽  
Adaptive Controller ◽  
Closed Loop System ◽  
Actual System ◽  
Levitation System ◽  
Magnetic Levitation System ◽  
Control Accuracy

In view of parameter uncertainty in the magnetic levitation system, the adaptive controller design problem is investigated for the system. Nonlinear adaptive controller based on backstepping is proposed for the design of the actual system with parameter uncertainty. The controller can estimate the uncertainty parameter online so as to improve control accuracy. Theoretical analysis shows that the closed-loop system is stable regardless of parameter uncertainty. Simulation results demonstrate the effectiveness of the presented method.

Hybrid controller with recurrent neural network for magnetic levitation system

2005 ◽  
Vol 41 (7) ◽  
pp. 2260-2269 ◽  
Author(s):  
Faa-Jeng Lin ◽  
Hsin-Jang Shieh ◽  
Li-Tao Teng ◽  
Po-Huang Shieh
Keyword(s):  
Neural Network ◽  
Recurrent Neural Network ◽  
Magnetic Levitation ◽  
Hybrid Controller ◽  
Levitation System ◽  
Magnetic Levitation System

scholarly journals Stabilization of the Magnetic Levitation System

2021 ◽  
Vol 11 (21) ◽  
pp. 10369
Author(s):  
Štefan Chamraz ◽  
Mikuláš Huba ◽  
Katarína Žáková
Keyword(s):  
Closed Loop ◽  
Magnetic Levitation ◽  
Internal Model Control ◽  
Pass Filter ◽  
Low Pass Filter ◽  
First Order ◽  
Model Based ◽  
Model Control ◽  
Levitation System ◽  
Magnetic Levitation System

This paper contributes toward research on the control of the magnetic levitation plant, representing a typical nonlinear unstable system that can be controlled by various methods. This paper shows two various approaches to the solution of the controller design based on different closed loop requirements. Starting from a known unstable linear plant model—the first method is based on the two-step procedure. In the first step, the transfer function of the controlled system is modified to get a stable non-oscillatory system. In the next step, the required first-order dynamic is defined and a model-based PI controller is proposed. The closed loop time constant of this first-order model-based approach can then be used as a tuning parameter. The second set of methods is based on a simplified ultra-local linear approximation of the plant dynamics by the double-integrator plus dead-time (DIPDT) model. Similar to the first method, one possible solution is to stabilize the system by a PD controller combined with a low-pass filter. To eliminate the offset, the stabilized system is supplemented by a simple static feedforward, or by a controller proposed by means of an internal model control (IMC). Another possible approach is to apply for the DIPDT model directly a stabilizing PID controller. The considered solutions are compared to the magnetic levitation system, controlled via the MATLAB/Simulink environment. It is shown that, all three controllers, with integral action, yield much slower dynamics than the stabilizing PD control, which gives one motivation to look for alternative ways of steady-state error compensation, guaranteeing faster setpoint step responses.

Traffic Responsive Signal Timing Plan Generation based on Neural Network

2011 ◽  
pp. 229-240
Author(s):  
Azzam-ul-Asar ◽  
M. Sadeeq Ullah ◽  
Mudasser F. Wyne ◽  
Jamal Ahmed ◽  
Riaz-ul-Hasnain
Keyword(s):  
Neural Network ◽  
Closed Loop ◽  
Learning Rule ◽  
Loop System ◽  
Closed Loop System ◽  
Highway Capacity ◽  
Highway Capacity Manual ◽  
Real Time Traffic ◽  
Plan Selection ◽  
Artificial Neural Network Ann

This paper proposes a neural network based traffic signal controller, which eliminates most of the problems associated with the Traffic Responsive Plan Selection (TRPS) mode of the closed loop system. Instead of storing timing plans for different traffic scenarios, which requires clustering and threshold calculations, the proposed approach uses an Artificial Neural Network (ANN) model that produces optimal plans based on optimized weights obtained through its learning phase. Clustering in a closed loop system is root of the problems and therefore has been eliminated in the proposed approach. The Particle Swarm Optimization (PSO) technique has been used both in the learning rule of ANN as well as generating training cases for ANN in terms of optimized timing plans, based on Highway Capacity Manual (HCM) delay for all traffic demands found in historical data. The ANN generates optimal plans online to address real time traffic demands and thus is more responsive to varying traffic conditions.

scholarly journals A method for the synthesis of neural regulators for linear objects

2020 ◽  
pp. 111-120
Author(s):  
Dmitry Romannikov ◽  
Keyword(s):  
Neural Network ◽  
State Vector ◽  
Closed Loop ◽  
Loop System ◽  
Transient Processes ◽  
Unstable State ◽  
Closed Loop System ◽  
Neural Controller ◽  
Object State ◽  
Reward Function

The article proposes a method for the synthesis of a neural controller for closed-loop systems with linear objects. The scientific novelty of the proposed method lies in the fact that the neural controller, to the input of which the object state vector is fed, must be trained to stabilize in one of the possible desired values, and to ensure regulation in other desired values. For objects with an inaccessible state vector, it is possible to use the estimation vector of the object state vector. It is proposed to proportionally decrease/increase the signal of the state vector and increase/decrease the control signal formed by the neural regulator. Also, other advantages of the proposed method include: 1) the absence of the need for training on several desired values, which greatly simplifies and accelerates the training of the neural network, and also eliminates control errors in the range of values for which the neural controller was not trained; 2) the possibility of learning from an initially unstable state of a closed-loop system. The proposed method for the synthesis of a neural controller for a closed-loop system with a linear object was tested on the example of the synthesis of a controller for an object 1/s 3, which is unstable. A neural network is used as a regulator, which is proposed to be trained using one of the reinforcement learning methods (in the article, the Deterministic Policy Gradient method allowed us to obtain the best results). The resulting graphs of transient processes allow us to conclude about its successful application. The article ends with conclusions and considerations about further lines of research, which include the quality of the transient process and the possibility of adjusting it by changing the reward function, which will allow setting the graphs of transient processes.

Sign in / Sign up

Export Citation Format

Share Document