Nonlinear Vibration Research Of The Flexible Manipulator In Out-space Environment

With the rapid development of space technology and robotics, space flexible manipulator has been widely applied in the field of aerospace and robotics because of its light weight, low energy consumption and operational adaptability. Space flexible manipulator, which is usually made up of rigid joints and thin flexible link, is a typical rigid-flexible coupling systems. In the launch process and working in the out-space environment, the manipulator will recieve greater acceleration, excessive shock loads and vibration effects. So greater bending and strong residual vibration will appear in the working process. In addition, the nonlinear vibration of the flexible link has typical characteristics of nonlinear vibration. Therefore, the research on the nonlinear vibration of the flexible manipulator in the out-space environment has great theoretical significance and application value.Based on the flexible manipulator in out-space environment, this paper mainly focuses on the nonlinear vibration of flexible link.In this paper the main work is as follows:Firstly, three-dimensional solid model of a flexible manipulator is set up, and the natural frequency of the main components is calculated. Then using the component mode synthesis and the Lagrange equations the dynamic model of flexible manipulator is established.In the modeling process, using Euler-Bernoulli beam theory meeting the appropriate Clamped-mass boundary conditions, the plane bending deformation model is obtained, with the effect of the reverse and the tensile deformation omited.Based on the above model, the vibration behavior of the flexible manipulator is numerically simulated. The order of modal truncation, the link structure parameters, joint driving torque are compared and analyzed respectively, on the flexible manipulator nonlinear vibration characteristics.Then, dynamic model is set up by considering micro-gravity of the flexible manipulator and the simulation shows the nonlinear vibration characteristics of flexible manipulator. Using the dynamic model micro-gravity environment and the tip concentrated mass of the flexible manipulator is considered. The tip concentrated mass influence on the nonlinear vibration characteristics of flexible manipulator is analyzed. Furthermore, the research on the effects of the joint friction is done, and the nonlinear vibration characteristics have been received by considering the action of friction.Finally, based on large deformation hypothesis a new dynamic model of the flexible manipulator is set up. From its simulation the nonlinear vibration behavior with the large deformation of the flexible manipulator is obtained.