| At present,manual cleaning is often used in aircraft cleaning,which has low efficiency and potential safety hazards.With the increasing number of civil aircraft,it is an inevitable trend to replace manual cleaning with machine,therefore,it is of practical significance to study the aircraft cleaning robot.In order to increase the flexibility of the cleaning arm and reduce the power consumption,this paper designs the cleaning arm as a slender manipulator,considering the flexibility of slender manipulator in motion,the following aspects are studied:Firstly,the kinematics of the 5-DOF cleaning arm is analyzed based on the screw theory,and the relationship between the end pose and joint parameters is obtained;Flexible the slender rod in the manipulator,and the motion analysis and flexible deformation description of the flexible rod are carried out based on the modal analysis method in the hybrid coordinate system,and then established the dynamics theoretical model of the cleaning robot;Based on these,Lagrange method is used to establish the flexible dynamics equation for two link flexible manipulator and one link rigid-one link flexible manipulator,which revealed the variety of joint driven torque with the link parameters and modal coordinates.Secondly,the finite element modal analysis of the flexible arm is carried out,and the modal frequency and vibration pattern of the arm are obtained;four typical positions are selected for modal analysis of the double link,after comparing the natural frequencies under different movement poses,it is concluded that the natural frequency of the flexible link is not affected by the motion attitude.Thirdly,carry out the co-simulation based on ANSYS and ADAMS.The finite element analysis of the manipulator is carried out in ANSYS and imported into ADAMS to generate the ADAMS flexible dynamics model;under the same joint driven torque,the end-effector movement of flexible and rigid dynamics models is compared,and it is concluded that the flexible dynamics model has obvious elastic deformation,which indicates the necessity of vibration suppression.MATLAB modular programming method and ADAMS dynamics software were used to study the influence of joint parameters on the driven torque,the joint angle and joint pose are used as input to verify the correctness of Lagrange dynamics equation.Finally,the vibration suppression of the flexible cleaning arm is studied.The method of point-to-point trajectory planning in joint space is based on Fourier cosine series.The objective function is to minimize the maximum vibration at the end-effector,particle swarm optimization(PSO)is used to optimize the redundant parameters of the joint trajectory.The simulation results show that when the order of Fourier cosine series is equal to 6,the vibration at the end-effector is almost zero,which meets the accuracy requirements of the optimization,which validate the effectiveness and feasibility of the proposed method. |
