Study On Hybrid Force/Position Control Of Carbon Fiber Automatic Placement Manipulator

Carbon fiber composites have been widely used in the fields of aerospace and automotive parts manufacturing,with excellent properties of light weight and high strength.Automatic carbon fiber placement technology is an advanced method for machining of carbon fiber composite material,with flexible laying angle,program control,high production efficiency,can be used in the manufacture of complex components,the method has good development prospect in large aerospace composite component manufacturing.The automatic laying arm of carbon fiber is an important part of the automatic placement equipment of carbon fiber.In this paper,carbon fiber automatic placement manipulator as the research object,analyzes its kinematics and dynamics and other related issues,the two main factors affecting the component quality of the composite materials of carbon fiber placement technology of automatic production,laying position accuracy and pressing force,put forward an improved hybrid control scheme of force/position.The main work of this paper is as follows:Firstly,the kinematics of the automatic placement manipulator is analyzed.Based on the simplified model of manipulator,the kinematical equation of the manipulator is obtained by using the modified D-H method to establish the link coordinate system and the link parameter table.At the same time,the Jacobi matrix of the manipulator in the task space and tool space is obtained,which laid a foundation for the force/position control of the manipulator.Secondly,the dynamic characteristics of the automatic placement manipulator were studied.The Lagrange method is used to solve the dynamics equation of the manipulator and the solution method is simplified.On this basis,a general program for solving the dynamic equation of a 6-DOF manipulator is developed by MATLAB,providing a method for fast solving the dynamics equation of manipulator.Then,according to the requirements of carbon fiber placement,a hybrid control scheme of force/position is proposed.Based on the comprehensive analysis of computed torque control and the classical R-C controller,the control torque method of tool space is introduced into the R-C controller to form an improved force/position hybrid control scheme.The control scheme breaks through the limitation that the classical force/position controller only can control the force which along the fixed coordinate axis direction,and solve the force control problem of fiber placement process of pressure.Finally,the force and position control scheme is simulated and the simulation results verify the effectiveness and feasibility of the proposed control scheme.In this paper,through the analysis and Research on the force and position control of the carbon fiber placement manipulator,it lays a foundation for the research and development of the automatic placement or laying equipment.