Assembly Verification Of Flexible Cable Based On Viscoelastic Rod Model

With the development of science and intelligent manufacturing technology,modern electromechanical products are constantly pursuing high quality,high efficiency,and high precision.Because the complex electromechanical products represented by ships,automobiles,airplanes and spacecraft are constrained by electrical and mechanical performance,the quality fraction of their internal cables continues to increase.The assembly quality of flexible cables has become the key to affect the assembly efficiency and quality of the entire product.However,the cables inside the electromechanical products have many types,complex shapes,and small assembly space,it is very easy to cause wrong assembly,missing assembly,unreasonable layout or interference of the cable in the actual assembly process.To solve this problem,based on the theory of cable dynamic modeling,this paper explores the simulation of cable assembly proces's in a virtual environment to obtain a reasonable cable assembly sequence and assembly path.The main contents of this study are as follows:(1)This article summarizes and analyzes the theoretical achievements of mechanical modeling of one-dimensional flexible bodies,and uses the nonlinear mechanical model of the viscoelastic rod to complete the dynamic modeling of the cable.The spatial shape of the cable can be decomposed into the position of the centerline and the twist of the cross section.The finite element discrete thought is used to analyze the interaction force and moment generated by the cable under the condition of changing boundary conditions.At the same time,the influence of friction dissipation on the cable shape is considered,and the cable mechanics modeling problem is converted to the problem of solving dynamic differential equations.(2)Comprehensively compare the computational efficiency and accuracy of a variety of ordinary differential equation solving algorithms,this paper uses semi-implicit Euler method to solve the equation.The morphology of cables of different materials and the morphological changes of cables under different motion parameters can be obtained by simulation.The simulation form conforms to the law of cable movement,so as to initially verify the rationality of the model.(3)The dynamic motion test bench was built,using the binocular vision measurement method of the cable centerline projection.The experimental platform can obtain the spatial coordinates of the shape change of the cable under the given motion parameters.When the movement parameters of the cable physical model are given,the actual movement form and simulation form of the cable at each moment are compared,so that the average error of the simulation model is 5%,which further verifies the effectiveness and accuracy of the model.(4)The cable virtual assembly simulation module was developed and the dynamic model fast solution algorithm was integrated and optimized.The solution time of the cable under any discrete particle number model is less than its display time interval,realizing the real-time dynamic display of cable shape changes in a virtual environment.Finally,taking the satellite internal simulation station as an example,the relevant verification of the cable model establishment,assembly path planning and the determination of the assembly sequence of multiple cables is completed in the virtual assembly simulation module.The cable model verification and virtual assembly simulation show that the cable dynamic modeling based on the viscoelastic rod model proposed in this paper can accurately simulate the cable shape.The assembly process planning results obtained by using this theory can play an effective guiding role in actual production,and have strong theoretical research significance and practical application value.