Dynamic Analysis And Simulation Of Equipment Combined Arms For OM2’s Assembly And Disassembly Under Installation Condition

The equipment combined arms for OM2’s assembly and disassembly is a mechanical device tailored for the installation of OM2 optical components from the national “Shenguang-III” subproject.During the installation of the optical assembly,the folding arm swing,the telescopic arm pitching and the telescopic arm expansion and contraction of the dismounting device completes the rough position,and then the fine-adjustment movement is completed by the six directions of freedom of the dismounting head.Because the equipment has a large heavy load,and depends on visual aids in place,and requires high installation accuracy,accurate dynamic analysis of the disassembly and assembly equipment is required to better plan the trajectory of OM2 components.Firstly,in this paper selecting three different structure of the combined boom in the process of rough positioning.Based on the ANSYS software,the static checking with strength and rigidity is carried out on the main components such as the chassis,the folding arm,the telescopic arm and the hydraulic cylinders.The first six orders of natural frequencies and modes of these three types structure are obtained by modal analysis.The modal analysis provides the basis for the time integration step and Rayleigh damping selection of the transient analysis.The floating frame of reference formulation is used to model the dynamics of the equipment for OM2’s assembly and disassembly.The finite element method is used to discretely describe the deformation of the flexible body.The Lagrange equation is used to obtain the dynamic equation of a single flexible body,and then the Lagrange multiplier is used to introduce the constraint equations to assemble the system dynamic equation.The mass matrix is obtained from the kinetic energy of the flexible bodies.The elastic force and stiffness matrix are obtained from the elastic force virtual work.The virtual power of external force is used to obtain the generalized external force.The constraint equation and the constrained Jacobian matrix are obtained according to the relationship between the components.The system dynamic equations of disassembly and assembly equipment are obtained by substituting the kinetic energy,elastic force,generalized external forces and binding forces into the first-type Lagrange equation.The dynamic equations are a set of time-varying,strongly nonlinear,and strongly-coupled differential-algebraic equations.The differential-algebraic equations are solved by the generalized-α method.The displacement and velocity of the terminal point of the disassembly and assembly equipment under different conditions are obtained.The time response curve and the rigid body solution constrained to zero are compared with the ADAMS rigid body simulation solution.The results are quite consistent,verifying the accuracy of the multi-flexible system model for disassembly and assembly equipment.the theoretical basis is provided for the terminal trajectory optimization control.After the rough positioning is completed,the transient analysis of the ‘freezing’ boom structure of the equipment is performed.The curve of the transient impact load function in the fine-tuning motion is obtained by the acceleration and deceleration control method,and the two-direction fine-tuning movement is selected through the vibration mode of the previous third type struction to obtain the displacement and velocity curve of the end point of the disassembly and assembly equipment and the vibration period.