This dissertation, "Kinematics, Dynamics and Control of High Precision Parallel Manipulators" by Wing-fung, Jacob, Cheung, 張穎鋒, was obtained from The University of Hong Kong (Pokfulam, Hong Kong) and is being sold pursuant to Creative Commons: Attribution 3.0 Hong Kong License. The content of this dissertation has not been altered in any way. We have altered the formatting in order to facilitate the ease of printing and reading of the dissertation. All rights not granted by the above license are retained by the author. Abstract: Abstracts of thesis entitled Kinematics, Dynamics and Control of High Precision Parallel Manipulators Submitted by Cheung Wing Fung Jacob for the degree of Doctor of Philosophy at The University of Hong Kong in March 2007 End-point positioning accuracy, fast point-to-point motion travel and stable operation are essential in high-precision motion mechanisms for industrial applications such as semiconductor packaging. In this thesis, a high-precision 2-DOF planar parallel manipulator and a 4-DOF spatial parallel manipulator are developed to advance the motion capabilities of traditional XY table and overcome difficulties in the kinematics design and end-point positioning accuracy of existing parallel manipulators. Novel methods of kinematics design and optimization, dynamic modelling and advanced control strategies are integrated in a complete design of the proposed manipulators to achieve high-speed positioning of the end-effector to an accuracy of micrometer unit. Modular design approaches are developed for designing the kinematics structure of the proposed parallel manipulators. In this design process, consideration is given to ensuring that the kinematics design can be realized to the required tolerance using existing mechanical construction technology. A Monte-Carlo simulation method is developed to determine the workspace of the parallel manipulator, and a Jacobian decoupling approach is developed to verify that the workspace of the manipulator is free of internal singularity. Kinematics optimization is performed to suppress the kinematics error magnification effect so that the end-effector positioning accuracy matches the manufacturing tolerance of the linkages. A dynamic model is essential for motion analysis, capability estimation and controller design of the parallel manipulator. The derivation of the dynamic model is simplified using a nested approach whereby the 4-DOF parallel manipulator is decomposed into triangular mechanisms at the actuator level and at the end-effector level, resulting in a high degree of decoupling in the modelling process. Recursive Newton-Euler method is employed to determine the dynamic model. The response of the dynamic model is simulated using sinusoidal force profiles to drive the linear actuators of the manipulator. The results obtained from the kinematics design, optimization and dynamic modelling are used to develop prototypes of the planar and 4-DOF parallel manipulators for the purpose of experimentation. A traditional PID computed-torque controller is first designed for the 2-DOF planar and the 4-DOF parallel manipulators using a model-based approach. In view of the limitations of the computed-torque control method, a robust learning control method is developed to enhance the motion performance by minimizing the settling time and steady-state error of the parallel manipulators. A frequency-domain system identification approach is used to identify the high frequency dynamics of the manipulator. A robust control design method is employed to design a stable, fast tracking-response feedback controller with less sensitivity to high frequency disturbance, with the control parameters determined using genetic algorithm. A Fourier-series based iterative learning controller is added to the feedforward path of the controller to improve the settling time by reducing the dynamic tracking

The robotics is an important part of modern engineering and is related to a group of branches such as electric

Parallel structures are more effective than serial ones for industrial automation applications that require high precision and stiffness, or a high load capacity relative to robot weight. Although many industrial applications have adopted parallel structures for their design, few textbooks introduce the analysis of such robots in terms of dynamics

Parallel structures are more effective than serial ones for industrial automation applications that require high precision and stiffness, or a high load capacity relative to robot weight. Although many industrial applications have adopted parallel structures for their design, few textbooks introduce the analysis of such robots in terms of dynamics and control. Filling this gap, Parallel Robots: Mechanics and Control presents a systematic approach to analyze the kinematics, dynamics, and control of parallel robots. It brings together analysis and design tools for engineers and researchers who want to design and implement parallel structures in industry. Covers Kinematics, Dynamics, and Control in One Volume The book begins with the representation of motion of robots and the kinematic analysis of parallel manipulators. Moving beyond static positioning, it then examines a systematic approach to performing Jacobian analysis. A special feature of the book is its detailed coverage of the dynamics and control of parallel manipulators. The text examines dynamic analysis using the Newton-Euler method, the principle of virtual work, and the Lagrange formulations. Finally, the book elaborates on the control of parallel robots, considering both motion and force control. It introduces various model-free and model-based controllers and develops robust and adaptive control schemes. It also addresses redundancy resolution schemes in detail. Analysis and Design Tools to Help You Create Parallel Robots In each chapter, the author revisits the same case studies to show how the techniques may be applied. The case studies include a planar cable-driven parallel robot, part of a promising new generation of parallel structures that will allow for larger workspaces. The MATLAB® code used for analysis and simulation is available online. Combining the analysis of kinematics and dynamics with methods of designing controllers, this text offers a holistic introduction for anyone interested in designing and implementing parallel robots.

Parallel manipulators are characterized as having closed-loop kinematic chains. Compared to serial manipulators, which have open-ended structure, parallel manipulators have many advantages in terms of accuracy, rigidity and ability to manipulate heavy loads. Therefore, they have been getting many attentions in astronomy to flight simulators and especially in machine-tool industries.The aim of this book is to provide an overview of the state-of-art, to present new ideas, original results and practical experiences in parallel manipulators. This book mainly introduces advanced kinematic and dynamic analysis methods and cutting edge control technologies for parallel manipulators. Even though this book only contains several samples of research activities on parallel manipulators, I believe this book can give an idea to the reader about what has been done in the field recently, and what kind of open problems are in this area.

Robots are a key element in current industrial processes, as they can be applied to a number of tasks, increasing both quality and productivity. Traditionally, serial robots have been installed in factories, as their wide operating space allowed them to fulfill a number of tasks. However, due to their high moving mass and single kinematic chain structure, these robots present some disadvantages when high speed, accuracy or heavy load handling tasks have to be executed. Parallel robots provide an interesting alternative to these application fields, as their multiple kinematic chain structure offers increased stiffness, allowing reduced positioning errors, lighter mechanisms and increased load/weight ratios. In this book, Chapter One addresses a new control strategy for parallel manipulators based on L1 adaptive control. This latter is known for its decoupled control and estimation loops, enabling fast adaptation and guaranteed robustness. Chapter Two focuses on the control of parallel robots. Chapter Three reviews structure synthesis of fully-isotropic two-rotational and two-translational parallel robotic manipulators. Chapter Four reviews the new prototype of the two-legged, parallel kinematic walking robot CENTAUROB, developed at Hamburg University of Technology. Chapter Five analyzes and robustly controls the 6-DOF 3-legged Wide-Open parallel manipulator, using a Lyapunov analysis approach.