Study On The Control Of A Dual-manipulator Cooperative System Handling A Flexible Payload Based On Singular Perturbation

Recently, robot manipulator has been used in many fields. There are many scholars who have done much work in manipulating rigid load,while in many fields, such as shipbuilding, car and air craft, flexible material has been used largely. So far, there are few scholars who have done such work. The system composed of robot manipulators and flexible payload has characteristics as following: exceeding nonlinearity, strong coupling and infinite degree of freedom. In the process of handling flexible two actions will happen that are rigid and vibration. Considering the current conditions domestic and abroad, the study of manipulating flexible payload is underway and the methods of control aren't perfect. There are many questions needed to be solved.In this paper the study of two manipulators handling a flexible payload has been done. The contributions of this paper are the modeling and the controller that is based on the other's work. Firstly, the background and significance are introduced. The system of manipulator manipulating flexible payload is divided into two species single and cooperative and the conditions are introduced singly. The characteristics of current methods are analyzed.To a reasonable mathematical model based on actual physical system is often higher order differential equation. If the system has some small time constants, inertia, conductivity or capacitance, will be made as a mathematical model of the differential equation of a very high order, as well as a numerical characteristic pathological. Early on such systems approach is simply ignored the fast modal system to reduce the system's order. However, the large number of facts have proven that such a simplified model based on the design of the control effects of the design requirements are often far apart. Singular perturbation method is an effective tool for dealing with such issues. Its way is to ignore fast variable order to reduce system first, and then to improve the approximate degree of correction through the introduction of the boundary layer. Boundary Layer correction singular perturbation method to the solution of the problem as from the superposition of two parts: part is not taking into account the impact on the solution of the boundary layer, called singular perturbation problems, solutions; from another part of the boundary layer effects defined borders Correction of the layer. Clearly, the correction of the boundary layer only play a role in the boundary layer, and in the external away from the border region, its influence will disappear, therefore, in the external region, singular perturbation problems, the solutions from these two components of the drop band system can be used to approximate the original system dynamics, which is in fact equivalent in the two time scales within the scope of independent completion of the design task. On the dynamic system, this decomposition is actually time scales decomposition. In recent decades, the theory in mechanics, physics, astronomy, and many other aspects of the study, plays an increasingly important role.Flexible coordinated operation against manipulator system predecessors load finite element method has been used to establish a dynamic model, the paper changes to collate and re-validation of the model is derived, based on the introduction of the singular perturbation theory and the theory of the system The finite element model for the decomposition, through double-standard finally transform the slow-changing and fast subsystem subsystems to the purpose of the model reduction, thus simplifying the next controller design.If there exists one or more switching function, when the state system to the value of the switch function, the system automatically switch from one structure into another determine the structure, then the system has been described as a variable structure system. Corresponding control strategy known as variable structure control, also known as the sliding mode control, referred to as sliding control. Sliding because of sliding mode control with full adaptability, the method by scholars extensive attention. A practical system of arbitrary parameters are changing, uncertain parameters, the mathematical description is not accurate, and so on, the system will also be outside interference, particularly when complex systems, which were regarded as a perturbation of the system. However, due to system can be constructed variable structure control, these perturbations on the sliding do not have an impact, and as a result has strong system robustness. This paper is sliding notes that the control of the notable features of the singular perturbation slow decomposition of the change subsystem designed a sliding controller, to be used for tracking the desired trajectory.But there is also sliding control deficiencies, not continuous variable structure system in the actual realization of the delay in the system will cause buffeting. Research from the buffeting causes and nature, there is a simple way to reduce buffeting, and does not require any additional equipment and measures, need only appropriate choice of parameters in reaching law on it. In this paper, the slow change in the choice of controller is the index reaching law, namely: in order to achieve a rapid approach also undermine the purpose of buffeting; often at the same time reduce the increase in value. This paper continues to use this type of thinking, a fuzzy sliding adjustment in the control parameter control strategy, sliding in at the initial state of the election will be the larger, sliding switch in the smaller elections around Obviously, this paper is to design Fuzzy controller is a single-input single-output controller, and its input language is variable distance from the sliding surface, it is the linguistic variables sliding output parameters. This design of the system ultimately guarantees good trajectory tracking performance to ensure that the closed-loop system asymptotically stable, and ensured the sliding buffeting the weakening of control.Fast application subsystems chosen a wide range of optimal controller. Finally, when the standard conversion, given the coordinated operation of flexible load manipulator system coordination and control of the importation. In matlab environment and simulation procedures for the preparation of system simulation, and proved that the design of the effectiveness of the method.This paper mainly on the coordinated operation of flexible load manipulator system has done some preliminary work, as manipulator coordination flexible load operation is a very complex system, the system will encounter when dealing with many kinds of problems, this paper is mainly to solve the coordinate the operation of problems and object model design for the controller model, but flexible load operation coordinated manipulator system, much work needed in the future to complete the study.Some prepared work was done for two manipulators handling a flexible payload. Because it's a very complex system many problems will appear in dealing with the system. This paper mostly solved the problem of model and designed a controller to validate the veracity but there are many works remained needed to be solved.