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Based on the analysis of the classic genetic algorithm and the classic adaptive genetic algorithm, we introduced evolutionary algebra and individual fitness value ranking to guide the adaptive crossover rate and adaptive mutation rate, to improve the control accuracy of the bundling motor of the small diameter short rope automatic strapping machine. A PID controller based on an improved adaptive genetic algorithm is designed to weaken the degradation of excellent parameters in the evolution process. The MATLAB simulation shows that the improved adaptive genetic PID improves the convergence accuracy and convergence speed. The actual test results on stepper motors show that the improved adaptive genetic PID has shorter tuning time and lower overshooting compared to the classical genetic algorithm. [ABSTRACT FROM AUTHOR]

Composite materials are widely used in aerospace, automotive industry and medical equipment, where most of the structural parts are made of fiber laminates. Rotary braiding is one of the most important methods to prepare composite preforms. The ordinary rotary braided preforms have low porosity and dense yarns, but are single-layer structures after molding, which do not meet the needs of most applications. To solve the problem that traditional laminates are prone to delamination, this paper designs a flat cross-linked braiding process for the preparation of multilayer-interlocking composite panels. The carrier trajectory is analyzed, and the spatial coordinate system of the braided chassis is established by combining the effect of the end traction system on the morphology of the preform yarns. The numerical model of the preform is initially obtained by using cubic B-spline curve fitting, and an algorithm for gathering yarns towards the fabric center is proposed to optimize the numerical model. Experimental samples of flat cross-linked preforms are prepared according to the braiding process, and the reliability of the optimization algorithm is verified by comparing the yarn coordinates of the experimental samples with those of the optimized numerical model. [ABSTRACT FROM AUTHOR]

The leveraged carrier makes the yarn have a certain tension through the lever. However, the length of the lever greatly limits the yarn storage capacity of the carrier, especially for some large end braiding machines. When the carrier moves from the outer horn gear to the inner one, the distance between the carrier and the braiding ring is greatly reduced, and the yarn storage is difficult to satisfy the requirement, which seriously affects the preform quality. On the other hand, the yarn tension control of leveraged carriers is not stable, there are many sudden change points, which is easy to cause yarns abrasion, fuzzing and even fracture. To solve these problems, a rotating yarn compensation carrier is designed, and the dynamic model of the yarn system is established. The motion law of carriers on the four-layer end braiding machine is studied, and the kinematic model of the yarn traction system is established. Moreover, the yarn tension of carriers in the feeding and recovering stages are analyzed. The curves of the yarn tension and key structure movements are drawn by MATLAB software to study the influence of yarn winding number on the yarn tension. The numerical analysis results show that the yarn storage capacity of the rotating yarn compensation carrier can meet the working requirements of the 4-layer end braiding machine, and the yarn tension can be maintained with stable changes by increasing the number of winding turns of the rods. [ABSTRACT FROM AUTHOR]

A multi-motor synchronous control strategy of 3 D braider was applied to improve the braiding efficiency of the rotary three-dimensional braider. The deviation-coupled synchronous control structure hased on the speed loop and the cascaded Al)RC position synchronization controller were designed. Simulink was used to estal,lish the synchronization control model of two motors and make the simulation analysis. The follow-up performance and anti-interference ability of the parallel synchronous control structure and the deviation-coupled synchronous conti·01 structure with the speed coinpensator were compared, and the cascade ADRC Was introduced in the deviation-coupled synchronization structure. The. simulation results show thal the coupled synchronous control structure based on cascade ADRC cari achieve stal,le operation, good speed following performance and strong anti-interference ability, which will significantly improve the position synchronization accuracy of 3D braider and increase the braiding efficiency. [ABSTRACT FROM AUTHOR]

During the braiding process of carbon fiber yarn, the tension Of the yarn fluctuates obviously, which causes the problem of local fracture and fluffing under the action of variable stress. In order to reduce the fluctuation of the yarn tension and braid the carbon fiber yarn under a proper braiding tension, it is necessary to optimize the structural parameters of the braiding carrier for the. carbon fiber yarn. According to the braiding process and the carrier structure, the yarn tension model was established in stages; according to the principle of particle swarm optimization algorithm and the optimization goal, the structural parameters and the optimization objective function were selected, and the optimization range of the structural parameters were determined. The optimization of the structural parameters of the braiding carrier for carbon fiber yarn was completed with MatLab software. The simulation results show that by adjusting the starting angle, thread length, spring stiffness and pre-compressed length of the braiding carrier for carbon fiber yarn, the tension of the carbon fiber yarn can be satisfied with processing requirements, and the yarn tension fluctuation rate after the optimization of the release stage is 18.13% lower than the experimental result of the single compensation braiding carrier. [ABSTRACT FROM AUTHOR]