CONFIDENTIEL
My current research focuses on creating autonomous guidance laws for robotic system in the presence of uncertain parameters, external disturbances and measurement noise. I work mainly on flatness control, sliding mode control, extended state observer, interval observers, and machine learning control, with applications to autonomous robotics.
Linear automatic sampled systems analog electronic digital electronics, microcontrollers, automatism, robotic system, C programming, artificial intelligence
♦ C/C++
♦ Matlab/simulink
♦ VBA
♦ VHDL
♦ Python
♦ Labview
♦ Robotic engineer, December 2015 until now.
♦ Electronic engineer, September 2011 until December 2012: Responsible for the manufacturing and production team of electronic cards within the company Tunisia Led.
The automation revolution already helps in many tasks that are now performed by robots. Increases in the complexity of problems regarding robot manipulators require new approaches or alternatives in order to solve them. This project comprises a research in different available software for implementing easy and fast visual servoing tasks controlling a robot manipulator. It focuses on out-of-the-box solutions. Then, the tools found are applied to implement a solution for controlling an arm from Universal Robots. The task is to follow a moving object on a plane with the robot manipulator. The research compares the most popular software, the state-of-the-art alternatives, especially in computer vision and also robot control. The implementation aims to be a proof of concept of a system divided by each functionality (computer vision, path generation and robot control) in order to allow software modularity and exchangeability. The results show various options for each system to take into consideration. The implementation is successfully completed, showing the efficiency of the alternatives examined. The chosen software is MATLAB and Simulink for computer vision and trajectory calculation interfacing with Robotic Operating System (ROS). ROS is used for controlling a UR3 arm using ros_control and ur_modern_driver packages. Both the research and the implementation present a first approach for further applications and understanding over the current technologies for visual servoing tasks. These alternatives offer different easy, fast, and flexible methods to confront complex computer vision and robot control problems.
Theme: Contribution to the generation of optimal trajectories for differentially flat systems application to the case of a quadrotor.
Theme: Flatness Based tracking control for mobile robot
Theme: Design of an application to control the production line pvc cables
This work suggests flatness-based Active Disturbance Rejection Control (ADRC) to deal with the problem of trajectory tracking for Wheeled Mobile Robot (WMR). Based on the differential flatness theory, the nonlinear WMR system is transformed into two integral chains, which makes the creation of a state feedback controller easier. In order to improve the WMR tracking, slip and external environmental disturbance must be considered in the controller design. Therefore, an Extended State Observer (ESO) is created to estimate the obtained linearized system state and the extended state known as lumped uncertainties. The latter represent the total effects of slip and the external environmental disturbances to WMR. After that, according to the ESO results, a complementary element is added to the state feedback controller to compensate the effects of lumped disturbances. Simulation results are introduced to demonstrate the advantages of combining ADRC with flatness control. CLICK TO OPEN DOCUMENT
This paper proposes a guaranteed tracking controller for a Wheeled Mobile Robot (WMR) based on the differential flatness theory and the interval observer. Using the flatness property, it is possible to transform the non linear WMR model into a canonical Brunovsky form, for which it is easier to create a state feedback controller. Since, in most real applications, the WMR is subjected to uncertainties such as slip, disturbance and noise, control algorithms must be modified to take into account those uncertainties. Therefore, based on the information of the upper and lower limits of the initial condition and all the uncertainties, an interval observer that generates an envelope enclosing every feasible state trajectory is developed. After that, based on the center of the obtained interval observer, a new control law is proposed to guarantee the tracking performance of the WMR despite the existence of un-measurable states and bounded uncertainties. The closed-loop stability of the system is proven analytically using the Lyapunov theorem. A lot of numerical simulation is realized in order to demonstrate the efficiency of the suggested guaranteed tracking control scheme. CLICK TO OPEN DOCUMENT
This work proposes guaranteed trajectory tracking control for a quadrotor based on feedforward flatness control and an interval observer. Using the exact feedforward linearization based on the differential flatness property, it is proven that the nonlinear quadrotor model can be transformed into the linear canonical system for which it is easier to create a state feedback controller. Since the quadrotor is subject to bounded uncertainties (parameters, disturbances and noise), the state of this latter cannot be measured properly. Therefore, based on the information of the upper and lower limits of the initial condition, the uncertain parameters, the disturbance and the measurement noise, an interval observer that generates an envelope enclosing every feasible state trajectory is developed. After that, based on the center of the obtained interval observer, flatness feedforward control, combined with estimated feedback control, is proposed to improve the tracking performance of the quadrotor despite the existence of unmeasurable state and bounded uncertainties. The closed-loop stability of the system is proven analytical using the Lyapunov theorem. The numerical simulation is done in order to evaluate the proposed tracking control scheme and the interval observer design. CLICK TO OPEN DOCUMENT
This work proposes an optimal trajectory generation and a robust flatness–based tracking controller design to create a new performance guidance module for the quadrotor in dense indoor environments. The properties of the differential flatness, the B‐spline, and the direct collocation method are exploited to convert the constrained optimization problem into a nonlinear programming one, which can be easily resolved by a classic solver. After that, the obtained optimal reference trajectory is applied to the dynamic quadrotor model and two different flatness‐based controllers, namely, one based on feedback linearization and one based on feedforward linearization, are developed and compared to ensure the trajectory tracking despite the existence of disturbances and parametric uncertainties. Numerical simulation is executed to evaluate the proposed optimal trajectory generation approach and the robust tracking strategies. It turns out that the controller based on feedforward linearization outperforms the feedback linearization one in robustness and permits obtaining a performance guidance law for an uncertain quadrotor system. CLICK TO OPEN DOCUMENT
This paper proposes a robust tracking controller based on the state estimation for a quadrotor. Using the differential flatness theory, it is demonstrated that the quadrotor model can be changed to a linearized form which facilitate the creation of a state feedback controller. Since some state vectors of the obtained linearized model cannot be measured directly, a high gain observer is implemented to estimate them. After that, utilizing the estimation state obtained by the latter observer, a new guidance law is developed for the quadrotor enabling a robust tracking to the desired trajectory despite the existence of unmesurable states. The numerical simulation of the quadrotor system is done in order to evaluate the performance of the robust tracking control scheme CLICK TO OPEN DOCUMENT
In this paper, based on differential flatness theory, the motion control of a wheeled mobile robot is studied. However, a flatness-based controller is designed to ensure the trajectory tracking. Secondly, this paper deal about the complex chaotic behaviors which can appear in the dynamic trajectory of an mobile robot. Different mathematical tools have been used such as flatness control technique and non linear chaotic system. Simulation results for kinematic controller is presented to demonstrate the effectiveness of this approach.
CLICK TO OPEN DOCUMENTThis paper deals with the complex chaotic behavior that can appear in the dynamic trajectory of a mobile robot, when the robot is broken or partly damaged. However, a flatness-based controller is designed to ensure the trajectory planning and tracking. Different mathematical tools have been used such as the flatness control technique and non linear chaotic systems. The simulation results for the kinematic controller are presented to demonstrate the effectiveness of this approach.
CLICK TO OPEN DOCUMENTThis article briefly summarizes the theory of chaos and its applications. Firstly, we begin by describing chaos as an aperiodic bounded deterministic motion, which is sensitive to initial states and therefore unpredictable after a certain time. Then, fundamental tools of the chaos theory, used for identifying and quantifying chaotic dynamics, are shared. The paper covers a main numerical approach to identify chaos such as the Lyapunov exponents. Many important applications of chaos in several areas such as chaos in electrical and electronic engineering and chaos applications in robotics have been presented. An analysis of the reviewed publications is presented and a brief survey is reported as well.
CLICK TO OPEN DOCUMENTIn this work, the differential flatness property and the sliding mode controller design are proposed for a quadrotor in order to track a predefined reference trajectory despite the presence of uncertain parameters. Firstly, differential flatness is utilized to resolve the problem for trajectory generation and tracking for the quadrotor. Next, a sliding controller is combined with a flatness design to guarantee the robustness of the tracking strategy. The numerical simulations of quadrotor system are done in order to evaluate the performance of the suggested control scheme. CLICK TO OPEN DOCUMENT
This work proposes an optimal trajectory generation and a controller design for a mobile robot. The objective consists of creating a new performance guidance module for the mobile robot in a closed environment. The reference trajectory can be calculated by solving an optimization problem. The properties of the differential flatness, the B-spline and the direct collocation method are exploited to convert the constrained optimization problem into a nonlinear programming one that can be easily resolved by a classic solver. After that, the obtained optimal reference trajectory is used in the kinematic mobile robot model. A flatness-based controller is designed to ensure the trajectory tracking. The numerical simulations are done in order to evaluate the proposed optimal trajectory generation approach and the tracking strategy. CLICK TO OPEN DOCUMENT
♦ system analysis and control DOWNLOAD FILE (003830_systemanalysisandcontrol.pdf)
♦ electronic project DOWNLOAD FILE (114055_electronic-project.pdf)
♦ project DOWNLOAD FILE (152245_project.pdf)
♦ automatic linear DOWNLOAD FILE (202444_TP-automatic-linear.pdf)
♦ Numerical control of mechatronic systems DOWNLOAD FILE (203840_Numericalcontrolofmechatronicsystems.pdf)
♦ electronic DOWNLOAD FILE (185811_TD+TP-electronic.pdf)