Research on Anti-Fluctuation Control of Winding Tension System Based on Feedforward Compensation

In the fiber winding process,strong disturbance,uncertainty,strong coupling,and fiber friction complicate the winding constant tension control.In order to effectively reduce the influence of these problems on the tension output,this paper proposed a tension fluctuation rejection strategy based on feedforward compensation.In addition to the bias harmonic curve of the unknown state,the tension fluctuation also contains the influence of bounded noise.A tension fluctuation observer(TFO)is designed to cancel the uncertain periodic signal,in which the frequency generator is used to estimate the critical parameter information.Then,the fluctuation signal is reconstructed by a third-order auxiliary filter.The estimated signal feedforward compensates for the actual tension fluctuation.Furthermore,a time-varying parameters fractional-order PID controller(TPFOPID)is realized to attenuate the bounded noise in the fluctuation.Finally,TPFOPID is enhanced by TFO and applied to control a tension control system considering multi-source disturbances.The stability of the method is analyzed by using the Lyapunov theorem.Finally,numerical simulations verify that the proposed scheme improves the tracking ability and robustness of the system in response to tension fluctuations.

Adaptive RISE Control of Winding Tension with Active Disturbance Rejection

A winding system is a time-varying system that considers complex nonlinear characteristics,and how to control the stability of the winding tension during the winding process is the primary problem that has hindered development in this field in recent years.Many nonlinear factors affect the tension in the winding process,such as friction,structured uncertainties,unstructured uncertainties,and external interference.These terms severely restrict the tension tracking performance.Existing tension control strategies are mainly based on the composite control of the tension and speed loops,and previous studies involve complex decoupling operations.Owing to the large number of calculations required for this method,it is inconvenient for practical engineering applications.To simplify the tension generation mechanism and the influence of the nonlinear characteristics of the winding system,a simpler nonlinear dynamic model of the winding tension was established.An adaptive method was applied to update the feedback gain of the continuous robust integral of the sign of the error(RISE).Furthermore,an extended state observer was used to estimate modeling errors and external disturbances.The model disturbance term can be compensated for in the designed RISE controller.The asymptotic stability of the system was proven according to the Lyapunov stability theory.Finally,a comparative analysis of the proposed nonlinear controller and several other controllers was performed.The results indicated that the control of the winding tension was significantly enhanced.

Development of PLC-based Tension Control System

Fiber winding tension is an important factor in the molding techniques of composite material which influences the quality of winding product directly, and the tension control is a key technique in fiber winding techniques. This paper introduces a closed-loop tension control system with the programmable logic controller （PLC） with function modules as its control kernel, the alternating current （AC） servo motor as execute element and the radius-following device to accomplish the real-time radius compensation. The mechanism of the tension control system is analyzed and the numerical model is set up. The compensation technique of the radius of the scroll is analyzed. Experimental results show that the system is well qualified with high control precision and high reaction speed.

Design and Analysis of a Novel Tension Control Method for Winding Machine

Filament winding has emerged as the main process for carbon fiber reinforced plastic(CFRP) fabrication, and tension control plays a key role in enhancing the quality of the winding products. With the continuous improvement of prod?uct quality and e ciency, the precision of the tension control system is constantly improving. In this paper, a novel tension control method is proposed, which can regulate the fiber tension and transport speed of the winding process by governing the outputs of three di erent driven rollers(the torque of the unwind roll, the torque of the magnetic powder brake roller, and the speed of the master speed roller) in three levels. The mechanical structures and dynamic models of the driven rollers and idle rollers are established by considering the time?varying features of the roller radius and inertia. Moreover, the influence of parameters and speed variation on fiber tension is investigated using the increment model. Subsequently, the control method is proposed by applying fiber tension in three levels accord?ing to the features of the three driven rollers. An adaptive fuzzy controller is designed for tuning the PID parameters online to control the speed of the master speed roller. Simulation is conducted for verifying the performance and sta?bility of the proposed tension control method by comparing with those of the conventional PID control method. The result reveals that the proposed method outperforms the conventional method. Finally, an experimental platform is constructed, and the proposed system is applied to a winding machine. The performance and stability of the tension control system are demonstrated via a series of experiments using carbon fiber under di erent reference speeds and tensions. This paper proposes a novel tension control method to regulate the fiber tension and transport speed.

Variable Tension Control for Discontinuous Tape Winding of Composites Based on Constant Extension Ratio

Discontinuous tape winding, which has obvious advantages in large extension ratio winding, is widely used in the molding of composites. Therefore, the research on technological parameters becomes the focus of many scholars. However, how to accomplish the variable tension control is usually not fully considered. Accordingly, the constant extension ratio and the smoothness of winding process cannot be ensured. Aiming at the problem of tension control, this paper first gives a comparatively deep research on the control method and the interaction mechanism of tension, extension ratio, automatic lap and automatic rectification. Then, according to the winding process features, the mechanical device and the mathematical model of tension control system are established respectively. With regard to the characteristics of PID controller and fuzzy controller, the fuzzy self-tuning PID controller is designed. As a result, the variable tension control is realized during the winding and lapping process, and the constant extension ratio is guaranteed. Finally, a sample application is presented for demonstration. By presenting the variable tension control techniques for discontinuous tape winding, the constant extension ratio of tapes is achieved, the consecution and the automation degree of winding process is improved as well. Thus, the quality of wound products is guaranteed.

Precision Tension Control System Using Magnetic Particle Clutch

The control of the stability of the filament tension is one of the crucial techniques ensuring the component quality of the composite materials. The open-loop tension control system, with industrial control computer as the core, magnetic particle clutch as the actuator, equipped with compensation technique is researched and manufactured. It can assure the tension control stability of the yarn in filament winding process and increase the control precision of the whole system.

Web Tension Regulation of Multispan Roll-to-Roll System using Integrated Active Dancer and Load Cells for Printed Electronics Applications

The mass production of primed electronics can be achieved by roll-to-roll（R2R） printing system, so highly accurate web tension is required that can minimize the register error and keep the thickness and roughness of printed devices in limits. The web tension of a R2R system is regulated by the use of integrated load cells and active dancer system for printed electronics applications using decentralized multi-input-single-output（MISO） regularized variable learning rate backpropagation artificial neural networks. The active dancer system is used before printing system to reduce disturbances in the web tension of process span. The classical PID control result in tension spikes with the change in roll diameter of winder and unwinder rolls. The presence of dancer in R2R system shows that improved web tension control in printing span and the web tension can be enhanced from 3.75 N to 4.75 N. The overshoot of system is less than ±2.5 N and steady state error is within ± 1 N where load cells have a signal noise of ±0.7 N. The integration of load cells and active dancer with self-adapting neural network control provide a solution to the web tension control of multispan roll-to-roll system.

ELECTRO-HYDRAULIC COMPOUND CONTROL METHOD AND CHARACTERISTIC OF CONTROL FOR TENSION SYSTEM WITH HIGH INERTIA LOADS

Based on the pressure regulation circuit adopting electro-hydraulic proportional relief valve to control tension, a new type of electro-hydraulic compound control circuit with throttle control unit is presented, which can obtain optimal dynamic damping ratio through real-time altering pressure-flow gain of the throttle control unit, improve the dynamic characteristic of tension follow-up control for the tension system with high inertia loads. Moreover, the characteristic when the cable linear velocity variation causes change of tension is investigated, and a compound control strategy is proposed. The theoretical analysis and experimental results show that the electro-hydraulic compound control circuit is effective and the characteristic of the compound control strategy is satisfactory.

A Study on a Wire Tension Adaptive Control System of a Multi-wire Saw in Computer Simulation

Based on the analysis of the mechanism of wire tension control by using torque motors in the multi-wire saw machining process, some mathematical models of a tension control system are studied, and an adaptive algo- rithm is designed for controlling the wire tension. In this algorithm of tension control, the rotation speeds and waving angle of motors are measured and fed back to the controller, and the NLMS（ normalized least mean squares） algorithm is used to calculate the adaptive correction value and control the wire tension accurately. The computer simulation results in Matlab software validate the high accuracy for controlling the system of the wire tension with the NLMS algorithm in the multi-wire saw machining process.

Tension Active Disturbance Rejection Control of Automatic Yarn Splicing Robots for Ring Spinning

Automatic splicing of interrupted yarns in ring spinning has always been a problem in the industry.Factors such as low yarn strengths and environmental influence on yarn tensions make it difficult to control the yarn tension during the robotic splicing process.The purpose of this research is to design active disturbance rejection control(ADRC)for a third-order nonlinear tension system subject to external disturbances.Firstly,a third-order extended state observer(ESO)is designed to achieve the suppression and the compensation of the internal modeling error and the external disturbances of the system.Secondly,the adaptive gain error feedback control and the filtering process are designed to reduce the influence of sensor noise on the disturbance observation.Finally,the tension control during the splicing process is simulated and experimented,and the experiments show that the method has good robustness in the tension tracking task under a dynamic environment,which verifies the effectiveness of the method.

Taxol Production in Suspension Cultures of Taxus chinensis as Affected by the Combination of Nutrient Feed with Dissolved Oxygen Control

Influence of the combination of nutrient feed with dissolved oxygen control on taxol production in suspension cultures of Taxus chinensis (Pilg.) Rehd. was investigated in bioreactors. Addition of feeding medium with 20 g/L sucrose on day 16 enhanced both the biomass and taxol production in 5-L bioreactors. Further investigation of the fed-batch cultures in a 20-L bioreactor showed that cultivation under a low dissolved oxygen tension (DOT) of 20% for the entire culture resulted in the highest taxol content of 0.98 mg/g DW, while the taxol production was lower than that with 40% and 60% DOT. Moreover, taxol accumulation was remarkably improved by the cultivation of cells initially under DOT of 60% for 20 d followed by changing the DOT to 20% for another 12 d. By combining the use of these two strategies, a maximum taxol content of 18.7 mg/L was obtained in a 20-L bioreactor.

Intelligent Winding Machine of Plastic Films for Preventing Both Wrinkles and Slippages

Flexible continuous plastic films are used to produce various products, including optical films and packaging materials, because plastic film is suited to use in mass production manufacturing processes. Generally, the web handling process is applied to convey the plastic film, which is ultimately rewound into a roll using a rewinder. In this case, wrinkles, slippage and other defects may occur if the rewinding conditions are inadequate. In this paper, the authors explain the development of a rewinder system that prevents wound roll defects—primarily starring and telescoping. The system is able to prevent such defects by optimizing the rewinding conditions of tension and nip-load. Based on the optimum design technique, the tension and nip-load are calculated using a 32-bit personal computer. Our experiments have also empirically shown that this rewinder system can prevent roll defects when applying optimized tension and nip-load. Additionally, inexperienced operators can control this system easily.

Designing of Hot Strip Rolling Mill Control System

Aimed at the complex demand of hot strip rolling mill in practicing, the configuration of the coiler and the technological process is analyzed. The arithmetic of coiling tension and the control process is introduced. The frame of the tension adjusting system is given. The coiler control system hardware is designed. The system is designed scientifically with steady control and meets demand of the market.

Looper-Tension Sliding Mode Control for Hot Strip Finishing Mills

An innovative sliding mode controller for looper and tension control in hot strip finishing mills was developed based on approximately linearized model. Firstly, a fictitious controller of the reduced order subsystem was designed according to desired dynamics, by which, the angle and tension loops were decoupled on the sliding manifold. Then, a sliding mode controller was used to validate finite time convergence of the state vector to the manifold which guaranteed the stability and performances of the overall system. This solution was considered owing to its well- known robustness and simplicity characteristics concerning disturbances and unmodelled dynamics. Simulation results showed the effectiveness of the proposed controller compared with conventional ones.

Modeling and Analysis of Interstand Tension Control in 6-high Tandem Cold Rolling Mill

The interstand tension control is one of the most important ways to meet tight tolerances for strip product quality during tandem cold rolling process. Using coordinate analysis and parabolic approximation for the mass flow balance principle, the strip velocities eliminating the use of forward slips and backward slips were calculated. In order to reduce the effect of roll eccentricity on the tension measurement, a filter based on bilinear transformation was de- signed. Applying a first-order Taylor series approximation, the transfer function matrix model of interstand tension stress was derived. The actual measurements on-site and the final calculation results showed that the established model had high calculation accuracy and was beneficial for interstand tension control of random cold rolling process.

Looper-Tension H_∞ Control for Hot Strip Finishing Mills

The development of an innovative H∞ controller for looper and tension control in hot strip finishing mills is traced based on approximately linearized model. This solution has been considered thanks to its well- known robustness and simplicity characteristics concerning disturbances' attenuation. The controller is designed based on an optimal problem with linear matrix inequality (LMI) constraints, and the problem is solved by the mincx function of Matlab LMI Toolbox. Simulation results show the effectiveness of the proposed controller compared with conventional ones.

Non-stationary Subdivision for Exponential Polynomials Reproduction

In this paper we develop a novel approach to construct non-stationary subdivision schemes with a tension control parameter which can reproduce functions in a finite-dimensional subspace of exponential polynomials. The construction process is mainly implemented by solving linear systems for primal and dual subdivision schemes respectively, which are based on different parameterizations. We give the theoretical basis for the existence, uniqueness, and refinement rules of schemes proposed in this paper. The convergence and smoothness of the schemes are analyzed as well. Moreover, conics reproducing schemes are analyzed based on our theory, and a new idea that the tensor parameter ωk of the schemes can be adjusted for conics generation is proposed.