Nonlinear control of vehicles and robots
Control techniques are indispensable in the design of robots and modern vehicles. Using feedback control, the safety and efficiency of these mechanical systems can considerably be improved. In order to achieve good control performances, the mathematical model of the controlled mechanical system has to be taken into consideration during control algorithm design. The dynamic models of vehicles and robots are nonlinear. The presented book first briefly outlines the most important nonlinear control algorithms that can be applied for the control of mechanical systems. The very first requirement of each control system is the closed loop stability. This is the reason why the stability analysis methods for nonlinear systems are presented in detail. Basic nonlinear control methods (feedback linearization, backstepping, sliding control, receding horizon control) that can be applied for mechanical systems are also reviewed. For efficient controller design, the knowledge of the dynamic model of controlled mechanical system is inevitable. A framework for the modeling of vehicles and robots is introduced. Starting from the dynamic model of rigid bodies, the mechanical models of robotic manipulators, ground, aerial and marine vehicles are presented. The nonlinear effects that appear in the models of different mechanical systems are discussed. The control of robots and different type of vehicles is discussed in separate chapters. The model based tracking control of robotic manipulators is addressed in different approaches. Firstly it is assumed that the parameters of the mathematical model of the robotic system are known. For such systems the classical robot control methods (such as cascade control, nonlinear decoupling and hybrid position/force control) are presented. For the control of robots with unknown parameters selftuning, adaptive control is proposed. If the robot prescribes a path including sharp corners, backstepping control techniques are suggested. The ground vehicles generally move in an unknown environment with stationary or moving obstacles. Some control algorithms are proposed for these systems that take into consideration the static and dynamic obstacles based on input-output linearization and receding horizon control techniques. Receding horizon control is also applied for the control of aircrafts. For nonlinear ship control, the acceleration feedback can be combined with nonlinear PID control. Adaptive control techniques can be applied for ships with unknown parameters. The control of 6 degrees of freedom ships is solved using back-stepping control techniques. Non-smooth nonlinearities such as friction and backlash severely influence the control performance of mechanical systems. A piecewise linearly parametrized model is introduced to describe the frictional phenomenon in mechanical control systems. The behavior of the control system with Stribeck friction and backlash is analyzed in a hybrid system approach. In the appendices of the book the kinematic and dynamic foundations of physical systems and the basis of differential geometry for control problems are presented. The book is aimed at researchers who are interested in modern control algorithms and advanced modeling techniques of the most common mechatronic systems: vehicles and robots.
mechanical models of robotic manipulators
scientific article; zbMATH DE number 5793300