A practical robust yaw servo architecture of ROVs by multi-vector propulsion and nonlinear controller

2020 ◽  
Vol 42 (15) ◽  
pp. 2908-2918
Author(s):  
Dalei Song ◽  
Lin Li ◽  
Changbin Wang ◽  
Renyu Hou ◽  
Chong Li
Keyword(s):  
High Performance ◽  
Complex Model ◽  
Servo Control ◽  
Delay Constraint ◽  
Nonlinear Controller ◽  
Robust Controller ◽  
External Disturbances ◽  
Yaw Control ◽  
Communication Problems ◽  
Nonlinear Hydrodynamics

Multi-vector arrangement is a novel propulsion architecture for remotely operated vehicles (ROV) because of its high manoeuvrability and efficiency, but the influence on the ROV dynamics and attitude servo control has not yet been clearly evaluated. This study fully investigated the kinematic behaviours of a hexagonal multi-vector propulsion ROV with communication delay constraint and reduced the complex model for precision control system design. An enhanced model-based PI robust controller (EMPRC) based on the nominal model is proposed to solve the nonlinear hydrodynamics and communication problems with high performance yaw control, whose stability is also analysed. The conventional proportional-integral-derivative (PID) and integral separation PID are used in the experiments for comparison. The results indicate that the proposed EMPRC can effectively track the desired attitude and reject the external disturbances, while the conventional ones are limited by the nonlinear dynamics and communication delays. The improvement is 3x on average in terms of overshoot, settling time and anti-disturbance recovery time compared to conventional algorithms and proves this proposed novel EMPRC is a practical solution for multi-vector propulsion ROVs.

scholarly journals A Novel Modified Super-Twisting Control Augmented Feedback Linearization for Wearable Robotic Systems Using Time Delay Estimation

Micromachines ◽  
2021 ◽  
Vol 12 (6) ◽  
pp. 597
Author(s):  
Brahim Brahmi ◽  
Ibrahim El Bojairami ◽  
Tanvir Ahmed ◽  
Asif Al Zubayer Swapnil ◽  
Mohammad AssadUzZaman ◽  
...  
Keyword(s):  
Time Delay ◽  
Feedback Linearization ◽  
High Performance ◽  
Time Delay Estimation ◽  
Robotic Systems ◽  
External Disturbances ◽  
Uncertain Dynamics ◽  
Control Scheme ◽  
Twisting Control ◽  
Dynamics Stability

The research presents a novel controller designed for robotic systems subject to nonlinear uncertain dynamics and external disturbances. The control scheme is based on the modified super-twisting method, input/output feedback linearization, and time delay approach. In addition, to minimize the chattering phenomenon and ensure fast convergence to the selected sliding surface, a new reaching law has been integrated with the control law. The control scheme aims to provide high performance and enhanced accuracy via limiting the effects brought by the presence of uncertain dynamics. Stability analysis of the closed-loop system was conducted using a powerful Lyapunov function, showing finite time convergence of the system’s errors. Lastly, experiments shaping rehabilitation tasks, as performed by healthy subjects, demonstrated the controller’s efficiency given its uncertain nonlinear dynamics and the external disturbances involved.

Real-Time Planning and Nonlinear Control for Quadrupedal Locomotion With Articulated Tails

2021 ◽  
Vol 143 (7) ◽  
Author(s):  
Randall T. Fawcett ◽  
Abhishek Pandala ◽  
Jeeseop Kim ◽  
Kaveh Akbari Hamed
Keyword(s):  
Real Time ◽  
Degrees Of Freedom ◽  
Center Of Mass ◽  
Hierarchical Control ◽  
Nonlinear Feedback ◽  
Nonlinear Controller ◽  
External Disturbances ◽  
Quadrupedal Locomotion ◽  
Control Scheme ◽  
High Level

Abstract The primary goal of this paper is to develop a formal foundation to design nonlinear feedback control algorithms that intrinsically couple legged robots with bio-inspired tails for robust locomotion in the presence of external disturbances. We present a hierarchical control scheme in which a high-level and real-time path planner, based on an event-based model predictive control (MPC), computes the optimal motion of the center of mass (COM) and tail trajectories. The MPC framework is developed for an innovative reduced-order linear inverted pendulum (LIP) model that is augmented with the tail dynamics. At the lower level of the control scheme, a nonlinear controller is implemented through the use of quadratic programming (QP) and virtual constraints to force the full-order dynamical model to track the prescribed optimal trajectories of the COM and tail while maintaining feasible ground reaction forces at the leg ends. The potential of the analytical results is numerically verified on a full-order simulation model of a quadrupedal robot augmented with a tail with a total of 20 degrees-of-freedom. The numerical studies demonstrate that the proposed control scheme coupled with the tail dynamics can significantly reduce the effect of external disturbances during quadrupedal locomotion.

Real-time nonlinear speed control of an induction motor based on a new advanced integral backstepping approach

2019 ◽  
Vol 42 (2) ◽  
pp. 244-258 ◽  
Author(s):  
Bilel Aichi ◽  
Mohamed Bourahla ◽  
Khedidja Kendouci ◽  
Benyounes Mazari
Keyword(s):  
Real Time ◽  
Induction Motor ◽  
High Performance ◽  
Control Method ◽  
Current Control ◽  
Lyapunov Theory ◽  
External Disturbances ◽  
Low Speed ◽  
Backstepping Approach ◽  
Time Motor

This work proposes a robust control scheme of a three-phase induction motor using a new Backstepping approach based on variable gains. Because of the saturation blocks that are essential to protect the control system, the use of conventional integral Backstepping could lead to a modest performance represented by overshooting and strong vibrations in transitional regimes that cause overcurrent. To develop an efficient and simple control algorithm, the variable gains propriety is used in the speed controller to offer a quick response without overshooting with good robustness against external disturbances. The same property has been introduced in current regulation by a different mean in order to develop a new solution to solve obstacles related to very low-speed operations. The asymptotic stability of the global control is proven by Lyapunov theory. The improvement of the new version compared with the classical one was verified by a brief comparative study based on simulation results. The proposed algorithm has been implemented in a dSPACE DS 1104 card, to analyze the real-time motor performance, and to test control sensitivity against parametric variations. The obtained results show a remarkable improvement of the new control concerning rapidity and stability of transient regimes, overtaking elimination and reduction of starting current, with a low algorithm sensitivity against parametric variations. We have also been able to confirm that the new current control method can guarantee optimal regulation in order to achieve a high-performance operation at very low-speed zones, in the presence of various internal and external disturbances.

Radiation Transport Simulation Results Assessment Through Comparison With Reduced Complexity Analytic and Computational Models (LA-UR-20-22342)

2020 ◽  
Author(s):  
Tyler J. Remedes ◽  
Scott D. Ramsey ◽  
Joseph H. Schmidt ◽  
James Baciak
Keyword(s):  
Spatial Distribution ◽  
Neutron Flux ◽  
High Performance ◽  
Computational Models ◽  
Radiation Transport ◽  
Complex Model ◽  
Spent Fuel ◽  
Fundamental Physics ◽  
Analysis Process ◽  
Reduced Complexity

Abstract In the past when faced with solving a non-tractable problem, scientists would make tremendous efforts to simplify these problems while preserving fundamental physics. Solutions to the simplified models provided insight into the original problem. Today, however, the affordability of high-performance computing has inverted the process for analyzing complex problems. In this paradigm, results from detailed computational scenarios can be better assessed by “building down” the complex model through simple models rooted in the fundamental or essential phenomenology. This work demonstrates how the analysis of the neutron flux spatial distribution behavior within a simulated Holtec International HI-STORM 100 spent fuel cask is enhanced through reduced complexity analytic and computational modeling. This process involves identifying features in the neutron flux spatial distribution and determining the cause of each using reduced complexity computational and/or analytic model. Ultimately, confidence in the accuracy of the original simulation result is gained through this analysis process.

Robust Guidance Control for Nonholonomic AGV Based on First Order Dynamic Sliding Mode Techniques

2013 ◽  
Vol 709 ◽  
pp. 583-588
Author(s):  
Jin Hua Ye ◽  
Di Li ◽  
Shi Yong Wang ◽  
Feng Ye
Keyword(s):  
High Performance ◽  
Sliding Mode ◽  
Path Following ◽  
Lyapunov Theory ◽  
External Disturbances ◽  
Guidance Control ◽  
First Order ◽  
Control Scheme ◽  
The Impact ◽  
Dynamic Sliding Mode

This paper develops a high performance guidance controller for automated guided vehicle (AGV) with nonholonomic constraint. In this controller, the path following method in the Serret-Frenet frame is used for driving the AGV onto a predefined path at a constant forward speed. Moreover, a first order dynamic sliding mode controller is proposed, not only to overcome the impact of unknown model uncertainties and external disturbances of the system, but also to weaken the chattering in the standard sliding mode control. The global asymptotic stability and robustness of the system is proven by the Lyapunov theory and LaSalles invariance principle. Simulation results show the validity of the proposed guidance control scheme.

Robust BackStepping Control Based DRNN for Flight Simulator

2010 ◽  
Vol 139-141 ◽  
pp. 1708-1713 ◽  
Author(s):  
Dong Kai Shen ◽  
Jing Jing Wang ◽  
Zheng Hua Liu
Keyword(s):  
High Performance ◽  
Design Procedure ◽  
Backstepping Control ◽  
Flight Simulator ◽  
System Control ◽  
Control Performance ◽  
External Disturbances ◽  
Motion Simulator ◽  
Backstepping Controller ◽  
Simulation Results

Flight motion simulator is one kind of servo system with uncertainties and nonlinearities. To acquire higher frequency response and good robustness for the flight simulator, we present a Backstepping controller based on a Diagonal Recurrent Neural Network (DRNN) to work out this problem. For one thing, the design procedure of the robust Backstepping controller is described. Subsequently, the principle and the design steps of DRNN are analyzed and expatiated respectively. In the end, simulation results on the flight motion simulator show that robust backstepping control based on DRNN can compensate for external disturbances and enhance robustness of the system control performance. Therefore both robustness and high performance of the flight motion simulator are achieved.

Design of robust controller for high performance servo track writer

2007 ◽  
Author(s):  
Jae Sang Yun ◽  
Choong Woo Lee ◽  
Hyun Jae Kang ◽  
Chung Choo Chung
Keyword(s):  
High Performance ◽  
Robust Controller

High Performance Power Conditioning System Using Dynamic-Game-Theory-Based Variable Structure Controller

2013 ◽  
Vol 284-287 ◽  
pp. 2367-2370
Author(s):  
En Chih Chang ◽  
Chun An Cheng ◽  
Chien Hsuan Chang ◽  
Hung Liang Cheng
Keyword(s):  
Game Theory ◽  
Tracking Control ◽  
High Performance ◽  
Dynamic Game ◽  
Hamiltonian Function ◽  
Variable Structure ◽  
Power Conditioning ◽  
External Disturbances ◽  
Parameter Variations ◽  
Dynamic Game Theory

In this paper, a variable structure controller based on dynamic game theory is proposed to reduce the effects of parameter variations, and external disturbances caused by uncertain systems. The variable structure controller (VSC) is a popular method for tracking control, since it can offer robustness to parameter variations, and external disturbances. However, the chattering problem occurs. The chattering may cause the degraded system performance and poor tracking control. Thus, the dynamic game theory is applied in VSC, to quickly, and precisely enforce the system states to the sliding surface, thus reducing the chattering. The stability and the convergence of the overall system are confirmed by the Hamiltonian function. The control algorithm has been realized for the actual power conditioning system (PCS) controlled by a TMS320F2812 DSP. With this proposed controller, an example that the controlled PCS under nonlinear loads yields the better robustness in performance. Experimental results validate the theoretical analysis.

Sign in / Sign up

Export Citation Format

Share Document