A Feedback Linearization-Based Motion Controller for a UWMR with Experimental Evaluations

SummaryIn this paper, the feedback linearization approach is used to introduce a motion controller for unicycle-type wheeled mobile robots (UWMRs). The output function is defined as a linear combination of the error state. The novel scheme is firstly tested in numerical simulation and compared with its corresponding experimental result. Three controllers are taken from the literature and compared to the proposed approach by means of experiments. The gains of the experimentally tested controllers are selected to obtain identical energy consumption. The Optitrack commercial vision system and Pioneer P3-DX UWMR are used in real-time experimental tests. In addition, two sets of experimental results for different motion tasks are provided. The results show that the proposed controller presents the best tracking accuracy.

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Optimal regulation of a cable robot in presence of obstacle using optimal adaptive feedback linearization approach

Robotica ◽

10.1017/s0263574714000691 ◽

2014 ◽

Vol 33 (4) ◽

pp. 933-952 ◽

Cited By ~ 4

Author(s):

M. H. Korayem ◽

H. Tourajizadeh ◽

A. Zehfroosh ◽

A. H. Korayem

Keyword(s):

Obstacle Avoidance ◽

Feedback Linearization ◽

Optimal Path ◽

Linear Quadratic Regulator ◽

Experimental Tests ◽

Linear Quadratic ◽

Optimal Regulation ◽

Cable Robot ◽

Optimal Controllers ◽

Feedback Linearization Approach

SUMMARYOptimal path planning of a closed loop cable robot, between two predefined points in presence of obstacles is the goal of this paper. This target is met by proposing a new method of optimal regulation for non linear systems while Dynamic Load Carrying Capacity (DLCC) of the robot is supposed as the related cost function. Feedback linearization is used to linearize the system while Linear Quadratic Regulator (LQR) is employed to optimize the DLCC of the system based on torque and error constraints. Obstacle avoidance for both the end-effector and cables is also considered by the aid of designing an adaptive local obstacle avoidance controller. As a result of linearized nature of the proposed optimal regulation and obstacle avoidance, fast calculation for real time applications is possible. Therefore, formulation of the optimal feedback linearization, together with calculating the DLCC of the robot based on the presented constraints is derived. Finally, a simulation study is performed to study the optimal dynamics and also the maximum DLCC of the cable robot in presence of obstacles. Simulation results are eventually compared with experimental tests conducted on IUST Cable Suspended Robot (ICaSbot) to verify the validity and efficiency of the proposed optimal controllers.

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A Robust Control Design Approach Combining Exact Linearization and High-Gain PI-Observer

Volume 5: 6th International Conference on Multibody Systems, Nonlinear Dynamics, and Control, Parts A, B, and C ◽

10.1115/detc2007-34344 ◽

2007 ◽

Cited By ~ 1

Author(s):

Yan Liu ◽

Dirk So¨ffker

Keyword(s):

Feedback Linearization ◽

Control Method ◽

High Gain ◽

Observer Design ◽

Input State ◽

Exact Linearization ◽

Practical Applications ◽

Robust Control Design ◽

Nonlinear Control Method ◽

Feedback Linearization Approach

This paper introduces a robust nonlinear control method combining classical feedback linearization and a high-gain PI-Observer (Proportional-Integral Observer) approach that can be applied to control a nonlinear single-input system with uncertainties or unknown effects. It is known that the lack of robustness of the feedback linearization approach limits its practical applications. The presented approach improves the robustness properties and extends the application area of the feedback linearization control. The approach is developed analytically and fully illustrated. An example which uses input-state linearization and PI-Observer design is given to illustrate the idea and to demonstrate the advantages.

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Dynamic modeling and design of controller for the 2-DoF serial chain actuated by a cable-driven robot based on feedback linearization

Proceedings of the Institution of Mechanical Engineers Part C Journal of Mechanical Engineering Science ◽

10.1177/09544062211027922 ◽

2021 ◽

pp. 095440622110279

Author(s):

Vahid Bahrami ◽

Ahmad Kalhor ◽

Mehdi Tale Masouleh

Keyword(s):

Dynamic Modeling ◽

Pid Controller ◽

Feedback Linearization ◽

Tracking Error ◽

Pid Controllers ◽

Serial Chain ◽

Simulation Results ◽

The Stability ◽

Feedback Linearization Approach ◽

Bounded Disturbance

This study intends to investigate a dynamic modeling and design of controller for a planar serial chain, performing 2-DoF, in interaction with a cable-driven robot. The under study system can be used as a rehabilitation setup which is helpful for those with arm disability. The latter goal can be achieved by applying the positive tensions of the cable-driven robot which are designed based on feedback linearization approach. To this end, the system dynamics formulation is developed using Lagrange approach and then the so-called Wrench-Closure Workspace (WCW) analysis is performed. Moreover, in the feedback linearization approach, the PD and PID controllers are used as auxiliary controllers input and the stability of the system is guaranteed as a whole. From the simulation results it follows that, in the presence of bounded disturbance based on Roots Mean Square Error (RMSE) criteria, the PID controller has better performance and tracking error of the 2-DoF robot joints are improved 15.29% and 24.32%, respectively.

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Modeling and trajectory tracking control of a two-wheeled mobile robot: Gibbs–Appell and prediction-based approaches

Robotica ◽

10.1017/s0263574718000565 ◽

2018 ◽

Vol 36 (10) ◽

pp. 1551-1570 ◽

Cited By ~ 11

Author(s):

Hossein Mirzaeinejad ◽

Ali Mohammad Shafei

Keyword(s):

Trajectory Tracking ◽

Dynamic Models ◽

Sliding Mode ◽

Tracking Accuracy ◽

Wheeled Mobile Robots ◽

Tracking Errors ◽

Trajectory Tracking Control ◽

Control Laws ◽

Control Approach ◽

Prediction Time

SUMMARYThis study deals with the problem of trajectory tracking of wheeled mobile robots (WMR's) under non-holonomic constraints and in the presence of model uncertainties. To solve this problem, the kinematic and dynamic models of a WMR are first derived by applying the recursive Gibbs–Appell method. Then, new kinematics- and dynamics-based multivariable controllers are analytically developed by using the predictive control approach. The control laws are optimally derived by minimizing a pointwise quadratic cost function for the predicted tracking errors of the WMR. The main feature of the obtained closed-form control laws is that online optimization is not needed for their implementation. The prediction time, as a free parameter in the control laws, makes it possible to achieve a compromise between tracking accuracy and implementable control inputs. Finally, the performance of the proposed controller is compared with that of a sliding mode controller, reported in the literature, through simulations of some trajectory tracking maneuvers.

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Principle and Simulation Study on Multi Point-Single Point Incremental Combined Forming for Sheet Metal

Materials Science Forum ◽

10.4028/www.scientific.net/msf.626-627.273 ◽

2009 ◽

Vol 626-627 ◽

pp. 273-278 ◽

Cited By ~ 1

Author(s):

X.J. Li ◽

Ming Zhe Li ◽

C.G. Liu ◽

Zhong Yr Cai

Keyword(s):

Sheet Metal ◽

Single Point ◽

Experimental Result ◽

Work Piece ◽

The Novel ◽

Forming Process ◽

Explicit Finite Element ◽

Forming Defect ◽

Forming Technology ◽

Elastic Cushion

Based on Multi-Point (MP) forming technology and Single-Point Incremental (SPI) forming technology, MP-SPI combined forming method for sheet metal is proposed, the principle and two different forming techniques are illustrated firstly. Then the paper is focused on numerical analysis for the novel forming technique with explicit Finite Element (FE) algorithm. During simulation of spherical work-piece, dimpling occurs as a main forming defect in MP-SPI combined forming process. Simulation results show that the dimpling defect can be suppressed effectively by using elastic cushion. An appropriate thickness of elastic cushion is necessary to prevent dimpling. And also the deformation of the work-piece is sensitive to the shape of elastic cushion. The combined forming test shows that the numerical simulation result is closed to the experimental result.

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