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Sliding mode control applied in trajectory-tracking of WMRs and autonomous vehicles

Solea, Razvan Constantin
Fonte: Universidade de Coimbra Publicador: Universidade de Coimbra
Tipo: Tese de Doutorado
ENG
Relevância na Pesquisa
46.45%
The thesis is structured as follows: • Chapter 2: Trajectory tracking problems are summarized. • Chapter 3: Kinematic and dynamic modeling of theWMRs and car-like robots are presented. • Chapter 4: The concept of sliding mode are first introduced. Then the fundamentals of SMC are summarized, including basic definitions, methods of sliding surface and control law design, robustness properties and the methods on handling chattering problems. New sliding-mode trajectory-tracking and slidingmode path-following controllers for WMRs and car-like vehicles, are also proposed in this chapter. • Chapter 5: The trajectory/path planning are developed, including the velocity profile. • Chapter 6: A model with two freedom degrees is considered for the HNC model. The user comfort is examined not only in the time domain, but also in the frequency domain. • Chapter 7: Experimental results obtained with the implementation of the proposed controllers in RobChair are summarized and discussed. • Chapter 8: Finally, conclusions are drawn and some suggestions for future work are provided.; Tese de doutoramento apresentada à Fac. de Ciências e Tecnologia da Universidade de Coimbra

Planejamento de movimento cinemático-dinâmico para robôs móveis com rodas deslizantes; Motion planning for kinematic-dynamic mobile robots with wheels sliding

Vaz, Daniel Alves Barbosa de Oliveira
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Dissertação de Mestrado Formato: application/pdf
Publicado em 30/11/2011 PT
Relevância na Pesquisa
46.57%
O planejamento de movimento é um dos problemas fundamentais em navegação autônoma para robôs móveis. Uma vez planejado o caminho, o robô executa o acompanhamento da trajetória, frequentemente, com o auxílio de um controlador em malha fechada. Este controlador tem o objetivo de minimizar os erros de acompanhamento, a fim de que a trajetória executada se aproxime da trajetória planejada. Entretanto a maioria dos planejadores de movimento não levam em consideração o modelo dinâmico do robô, dificultando assim o trabalho do controlador que executa o acompanhamento da trajetória. Incluindo as restrições cinemáticas e dinâmicas do modelo do robô, o custo computacional durante a fase de planejamento de trajetória será mais alto. Isto ocorre pois são necessárias mais variáveis para representar o espaço de estados do robô. No entanto ao levar em consideração tais restrições durante a fase de planejamento, as trajetórias geradas serão factíveis de serem acompanhadas. Os planejadores probabilísticos de movimento podem ser usados para minimizar o impacto do alto custo computacional, devido ao aumento de variáveis que representam o espaço de estados. Tais planejadores também são chamados de planejadores de movimento baseados em amostragem. A busca por um caminho livre de colisões entre dois estados é feito de maneira aleatória. Caso exista uma solução...

A proposed neural control for the trajectory tracking of a nonholonomic mobile robot with disturbances

Martins, Nardênio A.; De Alencar, Maycol; Lombardi, Warody C.; Bertol, Douglas W.; De Pieri, Edson R.; Filho, Humberto F.
Fonte: Universidade Estadual Paulista Publicador: Universidade Estadual Paulista
Tipo: Conferência ou Objeto de Conferência Formato: 330-338
ENG
Relevância na Pesquisa
66.57%
In this paper, a trajectory tracking control problem for a nonholonomic mobile robot by the integration of a kinematic neural controller (KNC) and a torque neural controller (TNC) is proposed, where both the kinematic and dynamic models contains disturbances. The KNC is a variable structure controller (VSC) based on the sliding mode control theory (SMC), and applied to compensate the kinematic disturbances. The TNC is a inertia-based controller constituted of a dynamic neural controller (DNC) and a robust neural compensator (RNC), and applied to compensate the mobile robot dynamics, and bounded unknown disturbances. Stability analysis with basis on Lyapunov method and simulations results are provided to show the effectiveness of the proposed approach. © 2012 Springer-Verlag.

Técnicas não lineares de controle e filtragem aplicadas ao problema de rastreamento de trajetórias de robôs móveis com deslizamento longitudinal das rodas; Nonlinear techniques of control and filtering applied to the trajectory tracking problem of mobile robots with longitudinal wheel slip

Juliano Gonçalves Iossaqui
Fonte: Biblioteca Digital da Unicamp Publicador: Biblioteca Digital da Unicamp
Formato: application/pdf
Publicado em 28/02/2013 PT
Relevância na Pesquisa
46.22%
Esta tese trata do problema de controle de trajetórias de robôs móveis não holonômicos com deslizamento longitudinal das rodas. As estratégias de controle propostas são projetadas usando dois modelos, um cinemático e um dinâmico, que consideram os deslizamentos longitudinais das rodas como parâmetros desconhecidos. A primeira estratégia de controle consiste em um controlador adaptativo projetado com base em um modelo cinemático que utiliza como entrada de controle, as velocidades angulares das rodas. Essas velocidades angulares são fornecidas por uma lei de controle cinemática que utiliza estimativa dos parâmetros de deslizamento desconhecidos, obtidas por meio de uma lei de adaptação. A segunda estratégia de controle consiste em um controlador adaptativo projetado com base em um modelo dinâmico simplificado que utilizam como entrada de controle, forças de propulsão aplicadas no centro das rodas. A lei de controle, que fornece essas forças, é projetada aplicando-se a técnica backstepping ao modelo dinâmico reduzido, que foi obtido com a utilização do método da dinâmica inversa. Os parâmetros de deslizamento longitudinal desconhecidos, necessários para a utilização do método da dinâmica inversa, são estimados por uma lei de adaptação. O filtro de Kalman unscented também é utilizado para estimar os parâmetros de deslizamento desconhecidos. Essas estimativas são utilizadas...

Construction of a WMR for Trajectory Tracking Control: Experimental Results

Silva-Ortigoza, R.; Márquez-Sánchez, C.; Marcelino-Aranda, M.; Marciano-Melchor, M.; Silva-Ortigoza, G.; Bautista-Quintero, R.; Ramos-Silvestre, E. R.; Rivera-Díaz, J. C.; Muñoz-Carrillo, D.
Fonte: Hindawi Publishing Corporation Publicador: Hindawi Publishing Corporation
Tipo: Artigo de Revista Científica
Publicado em 11/07/2013 EN
Relevância na Pesquisa
46.3%
This paper reports a solution for trajectory tracking control of a differential drive wheeled mobile robot (WMR) based on a hierarchical approach. The general design and construction of the WMR are described. The hierarchical controller proposed has two components: a high-level control and a low-level control. The high-level control law is based on an input-output linearization scheme for the robot kinematic model, which provides the desired angular velocity profiles that the WMR has to track in order to achieve the desired position (x∗, y∗) and orientation (φ∗). Then, a low-level control law, based on a proportional integral (PI) approach, is designed to control the velocity of the WMR wheels to ensure those tracking features. Regarding the trajectories, this paper provides the solution or the following cases: (1) time-varying parametric trajectories such as straight lines and parabolas and (2) smooth curves fitted by cubic splines which are generated by the desired data points {(x1∗, y1∗),..., (xn∗, yn∗)}. A straightforward algorithm is developed for constructing the cubic splines. Finally, this paper includes an experimental validation of the proposed technique by employing a DS1104 dSPACE electronic board along with MATLAB/Simulink software.

Singularity-Free Neural Control for the Exponential Trajectory Tracking in Multiple-Input Uncertain Systems with Unknown Deadzone Nonlinearities

Pérez-Cruz, J. Humberto; Rubio, José de Jesús; Encinas, Rodrigo; Balcazar, Ricardo
Fonte: Hindawi Publishing Corporation Publicador: Hindawi Publishing Corporation
Tipo: Artigo de Revista Científica
EN
Relevância na Pesquisa
46.39%
The trajectory tracking for a class of uncertain nonlinear systems in which the number of possible states is equal to the number of inputs and each input is preceded by an unknown symmetric deadzone is considered. The unknown dynamics is identified by means of a continuous time recurrent neural network in which the control singularity is conveniently avoided by guaranteeing the invertibility of the coupling matrix. Given this neural network-based mathematical model of the uncertain system, a singularity-free feedback linearization control law is developed in order to compel the system state to follow a reference trajectory. By means of Lyapunov-like analysis, the exponential convergence of the tracking error to a bounded zone can be proven. Likewise, the boundedness of all closed-loop signals can be guaranteed.

A robust trajectory tracking controller for four-wheel skid-steering mobile robots

Jun, Jae-Yun; Hua, Minh-Duc; Benamar, Faïz
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Relevância na Pesquisa
46.22%
A novel dynamic model-based trajectory tracking control law is proposed for a four-wheel differentially driven mobile robot using a backstepping technique that guarantees the Lyapunov stability. The present work improves the work of Caracciolo et al. (ICRA 1999), a dynamic feedback linearization approach, by reducing the number of required assumptions and the number of state terms. We also thoroughly investigate on a gain tuning procedure which is often overlooked for nonlinear controllers. Finally, the performance of the proposed controller is compared with the dynamic feedback linearization approach via simulation results which indicate that our controller is robust even in the presence of measurement noise and control time delay.; Comment: In the new version, a definition is added, and the presentation is improved

Global uniform asymptotic stabilization and k-exponential trajectory tracking of underactuated surface ships with non-diagonal inertia/damping matrices

Bao-Li, Ma
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 03/11/2011
Relevância na Pesquisa
46.45%
In this work, we investigate the state stabilization and trajectory tracking problems of underactuated surface ships with full state model of having non-diagonal inertia and damping matrices. By combining the novel state transformations, the direct Lyapunov approach, and the nonlinear time-varying tools, the stabilization and the trajectory tracking controllers are developed respectively guaranteeing global uniform asymptotic convergence of the state to the desired set point and global exponential convergence to the desired reference trajectory via mild persistent exciting conditions. Simulation examples are given to illustrate the effectiveness of the proposed control schemes.; Comment: 20 pages

Shape and Trajectory Tracking of Moving Obstacles

Lozev, Kamen
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 27/11/2011
Relevância na Pesquisa
46.72%
This work presents new methods and algorithms for tracking the shape and trajectory of moving reflecting obstacles with broken rays, or rays reflecting at an obstacle. While in tomography the focus of the reconstruction method is to recover the velocity structure of the domain, the shape and trajectory reconstruction procedure directly finds the shape and trajectory of the obstacle. The physical signal carrier for this innovative method are ultrasonic beams. When the speed of sound is constant, the rays are straight line segments and the shape and trajectory of moving objects will be reconstructed with methods based on the travel time equation and ellipsoid geometry. For variable speed of sound, we start with the eikonal equation and a system of differential equations that has its origins in acoustics and seismology. In this case, the rays are curves that are not necessarily straight line segments and we develop algorithms for shape and trajectory tracking based on the numerical solution of these equations. We present methods and algorithms for shape and trajectory tracking of moving obstacles with reflected rays when the location of the receiver of the reflected ray is not known in advance. The shape and trajectory tracking method is very efficient because it is not necessary for the reflected signal to traverse the whole domain or the same path back to the transmitter. It could be received close to the point of reflection or far away from the transmitter. This optimizes the energy spent by transmitters for tracking the object...

Sensitivity analysis of hybrid systems with state jumps with application to trajectory tracking

Saccon, Alessandro; van de Wouw, Nathan; Nijmeijer, Henk
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 11/06/2014
Relevância na Pesquisa
46.61%
This paper addresses the sensitivity analysis for hybrid systems with discontinuous (jumping) state trajectories. We consider state-triggered jumps in the state evolution, potentially accompanied by mode switching in the control vector field as well. For a given trajectory with state jumps, we show how to construct an approximation of a nearby perturbed trajectory corresponding to a small variation of the initial condition and input. A major complication in the construction of such an approximation is that, in general, the jump times corresponding to a nearby perturbed trajectory are not equal to those of the nominal one. The main contribution of this work is the development of a notion of error to clarify in which sense the approximate trajectory is, at each instant of time, a firstorder approximation of the perturbed trajectory. This notion of error naturally finds application in the (local) tracking problem of a time-varying reference trajectory of a hybrid system. To illustrate the possible use of this new error definition in the context of trajectory tracking, we outline how the standard linear trajectory tracking control for nonlinear systems -based on linear quadratic regulator (LQR) theory to compute the optimal feedback gain- could be generalized for hybrid systems.

Trajectory tracking control of kites with system delay

Baayen, Jorn H.
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 27/12/2012
Relevância na Pesquisa
46.22%
A previously published algorithm for trajectory tracking control of tethered wings, i.e. kites, is updated in light of recent experimental evidence. The algorithm is, furthermore, analyzed in the framework of delay differential equations. It is shown how the presence of system delay influences the stability of the control system, and a methodology is derived for gain selection using the Lambert W function. The validity of the methodology is demonstrated with simulation results. The analysis sheds light on previously poorly understood stability problems.; Comment: 10 pages, 9 figures

On Event Triggered Tracking for Nonlinear Systems

Tallapragada, Pavankumar; Chopra, Nikhil
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 05/01/2013
Relevância na Pesquisa
36.57%
In this paper we study an event based control algorithm for trajectory tracking in nonlinear systems. The desired trajectory is modelled as the solution of a reference system with an exogenous input and it is assumed that the desired trajectory and the exogenous input to the reference system are uniformly bounded. Given a continuous-time control law that guarantees global uniform asymptotic tracking of the desired trajectory, our algorithm provides an event based controller that not only guarantees uniform ultimate boundedness of the tracking error, but also ensures non-accumulation of inter-execution times. In the case that the derivative of the exogenous input to the reference system is also uniformly bounded, an arbitrarily small ultimate bound can be designed. If the exogenous input to the reference system is piecewise continuous and not differentiable everywhere then the achievable ultimate bound is constrained and the result is local, though with a known region of attraction. The main ideas in the paper are illustrated through simulations of trajectory tracking by a nonlinear system.; Comment: 8 pages, 3 figures. Includes proofs for all results

Visual servo trajectory tracking for a four rotor VTOL aerial vehicle

Hamel, Tarek; Mahony, Robert; Chriette, Abdelhamid
Fonte: Institute of Electrical and Electronics Engineers (IEEE Inc) Publicador: Institute of Electrical and Electronics Engineers (IEEE Inc)
Tipo: Conference paper
Relevância na Pesquisa
66.54%
An image-based visual servo control design is proposed for a four rotor vertical take-off and landing (VTOL) craft known as an X4-flyer accomplishing a trajectory tracking task. The approach taken is an image-based visual servo (IBVS) design that is applicable to under-actuated dynamic systems. The work is an extension of the authors earlier work to the trajectory tracking problem. Semi-global stability of the closed loop system is proved for bounded trajectories.

An output feedback algorithm for trajectory tracking in control affine nonlinear systems

Costa,V. A.; García,R. A.; Troparevsky,M. I.
Fonte: Latin American applied research Publicador: Latin American applied research
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/10/2003 EN
Relevância na Pesquisa
66.39%
In this work we present an output feedback algorithm that solves the trajectory tracking problem in control affine nonlinear systems. This algorithm, is an improvement, for this class of systems, of that of (Mancilla Aguilar et al. 2000a), since it reduces the chattering effect on the control while keeping the original performance. In addition, and via a high gain observer, it deals with discrete output measurements instead of the states, as the original algorithm does.

Trajectory tracking for the chaotic pendulum using PI control law

Perez,J.; Perez,J. P.; Rdz,F.; Flores,A.
Fonte: Sociedad Mexicana de Física Publicador: Sociedad Mexicana de Física
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/10/2013 EN
Relevância na Pesquisa
66.44%
This paper presents the application of trajectory tracking using adaptive neural networks to the double chaotic pendulum. The controller structure proposed is composed by a neural identifier and a PI Control Law. Experimental results with the chaotic pendulum showed the usefulness of the proposed approach. To verify the analytical results, an example of a dynamical network is simulated and a theorem is proposed to ensure the tracking of the nonlinear system.

Trajectory Tracking for Chaos Synchronization via PI Control Law between Roosler-Chen

Perez Padron,Joel; Perez Padron,Jose Paz; Rodriguez Ramirez,Francisco; Flores Hernandez,Angel
Fonte: Centro de Investigación en computación, IPN Publicador: Centro de Investigación en computación, IPN
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/06/2014 EN
Relevância na Pesquisa
66.44%
This paper presents an application of adaptive neural networks based on a dynamic neural network to trajectory tracking of unknown nonlinear plants. The main methodologies on which the approach is based are recurrent neural networks and Lyapunov function methodology and Proportional-Integral (PI) control for nonlinear systems. The proposed controller structure is composed of a neural identifier and a control law defined by using the PI approach. The new control scheme is applied via simulations to Chaos Synchronization. Experimental results have shown the usefulness of the proposed approach for Chaos Production. To verify the analytical results, an example of a dynamical network is simulated and a theorem is proposed to ensure tracking of the nonlinear system.

Trajectory Tracking Control in a Single Flexible-Link Robot using Finite Differences and Sliding Modes

Peza-Solís,J.F.; Silva-Navarro,G.; Castro-Linares,N. R.
Fonte: UNAM, Centro de Ciencias Aplicadas y Desarrollo Tecnológico Publicador: UNAM, Centro de Ciencias Aplicadas y Desarrollo Tecnológico
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/01/2015 EN
Relevância na Pesquisa
66.62%
In this article it is shown how the end effector position of a single flexible-link robot can be directly controlled by the angular position of its joint, so that, trajectory tracking in the end effector of the robot is possible by properly designing a reference trajectory for the joint angle. In order to ensure trajectory tracking of the angular position of the robot joint, a Sliding Modes Control (SMC) scheme is employed once the desired trajectory for the robot joint has been designed. SMC scheme is chosen because its known robust performance under dynamical disturbances and modeling inaccuracies. Then, the angular position of the robot joint plays the role of a virtual control input for the flexible dynamics of the link. Both, regulation and trajectory tracking of the end effector position are achieved by using the scheme devised in this work. The Finite Differences Method (FDM) is employed to simulate the closed loop performance of the flexible-link robot, because its dynamics are assumed to be governed by the undamped Partial Differential Equation (PDE) of the Euler-Bernoulli Beam (EBB).

Fast Adaptive Trajectory Tracking Control for a Completely Uncertain DC Motor via Output Feedback

Sira Ramírez,H.; Barrios Cruz,E.; Márquez Contreras,R.
Fonte: Centro de Investigación en computación, IPN Publicador: Centro de Investigación en computación, IPN
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/06/2009 EN
Relevância na Pesquisa
46.39%
An algebraic parameter identification method, developed for fast, on-line, computation of unknown linear system parameters, is here used for the fast adaptive output feedback control of a completely unknown dc motor, subject to constant perturbation load torques while solving a reference trajectory tracking task. An output feedback controller of the Generalized Proportional Integral (GPI) type, written in classical compensation network form, is proposed for the perturbed output trajectory tracking problem. The fast adaptation of system parameters is carried out, both, on the classical compensating network parameters and on the conformation of the feed-forward control input signal. Experimental results validate the effectiveness of the proposed approach.

Tracking Control for an Underactuated Two-Dimensional Overhead Crane

Liu,D. T.; Guo,W. P.
Fonte: UNAM, Centro de Ciencias Aplicadas y Desarrollo Tecnológico Publicador: UNAM, Centro de Ciencias Aplicadas y Desarrollo Tecnológico
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/08/2012 EN
Relevância na Pesquisa
56.44%
In this paper, the tracking control problem is considered for the payload transportation with an underactuated two-dimensional overhead crane. Two sliding mode controllers are designed to perform the trajectory tracking. One is proposed to control hoisting and lowering the suspended payload, and the other one is proposed to control both trolley positioning and payload swaying. Considering the second sliding mode controller is used to control two degrees of freedom (DOFs), a fuzzy inference algorithm is proposed to dynamically adjust the coupling factor between the two DOFs. The two controllers make the payload track a predefined trajectory and be safely transported as fast and accurately as possible with a small swing angle, and then place the payload at the desired position. Simulations are performed with the proposed controllers and the results show their effectiveness.

PID Control Law for Trajectory Tracking Error Using Time-Delay Adaptive Neural Networks for Chaos Synchronization

Pérez P.,Joel; Pérez,José P.
Fonte: Centro de Investigación en computación, IPN Publicador: Centro de Investigación en computación, IPN
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/06/2015 EN
Relevância na Pesquisa
66.44%
This paper presents an application of Time-Delay adaptive neural networks based on a dynamic neural network for trajectory tracking of unknown nonlinear plants. Our approach is based on two main methodologies: the first one employs Time-Delay neural networks and Lyapunov-Krasovskii functions and the second one is Proportional-Integral-Derivative (PID) control for nonlinear systems. The proposed controller structure is composed of a neural identifier and a control law defined by using the PID approach. The new control scheme is applied via simulations to Chaos Synchronization. Experimental results have shown the usefulness of the proposed approach for Chaos Production. To verify the analytical results, an example of a dynamical network is simulated and a theorem is proposed to ensure the tracking of the nonlinear system.