Optimal analysis and application of the warp tension control system for a rapier loom

Traditional proportional–integral–derivative (PID) control performance optimization is an essential method to improve a loom’s warp tension control performance. This work proposes an improved genetic algorithm optimized PID control scheme to overcome the decline in control performance of the traditional PID control algorithm in a loom’s warp tension control system. Through the decoupling analysis of loom motion mechanism, the establishment of warp tension model and the optimization of fitness evaluation mechanism of genetic algorithm can effectively overcome the problems of local optimal solution and algorithm degradation of genetic algorithm. Simulation experiments were carried out with the traditional PID, the integral separation PID, and the genetic PID in warp tension control. The results show the advantage of the genetic-PID algorithm to control warp tension stability. Ultimately, according to the functional characteristics of the loom mechanism, a tension control platform for experimental studies was established. The test results show that the maximum fluctuation range of warp tension is within [−2, +6] at the test speed of 850 rpm, which meets the requirements of long-term stable and reliable control of warp tension under different weaving conditions.

Application of embedded soft PLC in the control system of rapier loom

At present, the rapier loom has gradually become the mainstream equipment in the manufacturing industry. In order to make the rapier loom realize automated production and further improve the production efficiency of the rapier loom, improve the programmability of the system, and reduce the cost of system maintenance. The thesis developed a rapier loom control system based on embedded soft PLC, and carried out experiments and applications in the field. The contribution and innovation of this paper is to develop a complete low-cost control system, and through a genetic algorithm optimized PID algorithm to complete the more effective control of the loom tension system. The embedded soft PLC system proposed in this paper reduces the overall maintenance cost of the system and improves the programmability of the system. This text carries on the systematic scheme design to the embedded soft PLC from the hardware system and the software system respectively. First, according to the actual requirements, this article designs the overall scheme of the embedded software PLC hardware system with STM32F407ZGT6 as the core. Then this article is based on the embedded soft PLC hardware platform, according to the international standard of industrial control programming, writes the embedded soft PLC low-level driver software. Secondly, this article analyzes the factors that affect the warp tension during the operation of the rapier loom, and proposes the use of genetic algorithm to optimize the warp tension control method of the traditional PID algorithm. Finally, we conducted verification tests and on-site application debugging for the entire set of rapier loom embedded soft PLC control system. We controlled the warp tension as the main experimental object. The results show that this control system effectively improves the control accuracy of the warp tension of the rapier loom and meets the actual needs of industrial applications. The whole system has a good application prospect in the warp tension control of rapier looms.

Research on integral separation control of warp tension based on fuzzy parameter optimization

In textile machines, the stability of warp tension is one of the decisive factors for the reliability, stability and product quality of weaving process. In order to meet the improving requirement for weaving efficiency and fabric quality, it is proposed that a fuzzy optimization integral separation PID warp tension control scheme based on process sampling to improve the warp tension control level of loom. Aiming at the problems of time-varying, nonlinear and variable coupling in the warp tension control system of loom, the forming mechanism of warp tension is modeled and analyzed, and the sampling scheme of warp tension based on process is proposed. Based on the periodic change of warp tension at macro level and continuous fluctuation at micro level, the integral separation control and fuzzy optimization theory are introduced to optimize the control effect of the control system on the basis of classical PID control algorithm. Finally, the simulation and experiment show that the scheme can improve the tension controls performance and effectively reduce the tension error fluctuation.

An investigation of the effects of weave types on surface roughness of woven fabric

The fabrics intended for clothing have more emphasis on their appearance and handling characteristics such as luster, smoothness or roughness, stiffness or limpness, and draping qualities. Nowadays, evaluating fabric touch can be of great interest in the industry to match the quality needs of the consumer and the parameters for the manufacturing process. Throughout this study, the effect of weave types on the surface roughness of cotton woven fabric was investigated and analyzed. Three different weave types namely, plain 1/1, twill 1/3, and sateen 8/3 were investigated. The fabric parameters were 27*20Ne (warp/weft) count of yarn, 38*18 (EPC [Ends per Centimeters]/PPC [Picks per Centimeters]) thread density, and 710 CN/TEX (Cent-newton per Tex) with warp tension was produced by air-jet loom. The findings of this study revealed that the surface roughness values of all the fabrics increased regularly on moving from plain 1/1 weave to sateen 8/3 weave. But, the surface roughness of fabric in the weft direction is higher than in the warp direction. The weave type is statistically significant at a confidence interval of 95% and can effectively be used to describe the surface roughness for both warp and weft direction of woven fabrics. The pairwise comparison reveals that it is statistically significant for weave types in the warp and weft direction of the fabrics. This investigation and analysis of weave types on surface roughness of cotton woven fabrics help textile technologies and manufacturers to consider the weave types during the production of fabrics for different end applications.

Detection of Remote Sensing Warp Tension during Weaving on Plain Twill and Satin Fabric

Warp tensions were measured while a machine was operating on a woven cotton fabric with three different woven patterns. This study was carried out with image analysis methods using a high speed camera. Three weave pattern types: plain, twill and satin were woven on the same weaving machine, and thus it could be understood how weave pattern differences affect warp tension. Each of these three weaves was woven in three weft densities: 20, 28 and 45 wefts per cm. These fabrics were able to be made on a weaving machine with an automatic dobby. It was aimed to investigate warp tension differences for three basic weave patterns while keeping all machine settings constant. The weave settings of the dobby were changed for plain, twill and satin weaves. Warp tension calculation was based on the warp elasticity theory. Warp elasticises were measured by image processing methods in MATLAB using a high-speed camera. It was aimed to improve upon the new method of warp extension measurement of fabric when the loom is in operation. It was observed that the warp tension in plain fabric was higher than for twill and satin under the same conditions.

An Experimental Technique to Determine the Permissible Warp Tension Variation At the Required Pick Density

Weaving is considered to be the most versatile means of manufacturing fabric. Due to versatility, process control is mandatory to ensure the quality of the woven fabric becomes a diverse task with a broader scope. With the advent of technology speed of weaving has been drastically increased due to which variation in warp tension becomes an inevitable fact for value-added technical products. Further, variation in warp tension results in different pick density which causes a shade variation due to different amounts of dye penetration along with the fabric. Maintain constant pick density throughout weaving is considered as the most important aspect. The pick density is greatly affected by the warp gaiting tension at which the fabric is woven and experiment results revealed that the warp gaiting tension is considerably changed when the beam is weaved down. Authors attempt to statistically analyze the quantitative relationship between the warp gaiting tension and the pick density. However, due to the high level of variability of warp gaiting tension along the warp with slightly scattered nature of experimental data, setting up a relationship with adequate accuracy is beyond achievable. Hence the warp gaiting tension is first grouped using a statistical technique and established the relationship for each group. The level of accuracy for each model is evaluated at 95% of the confidence interval and thereby determined the permissible tolerance in warp gaiting tension under which the required pick density could be still achieved.

Changeover Process Assessment of Warp-Knitting Let-Off Equipped with Multispeed Electronic Let-Off System

Warp-knitted fabrics have gained increasing attention due to their excellent properties, and their production is strongly dependent on the warp-based electronic let-off system. Most of the existing control systems are single speed electron let-off structure, which brings a series of issues such as broken yarn, missed needle, and running thread caused by let-off delay, making it hard for manufacturer to produce the required fabrics. To fill the gap, this article proposes a new framework of a multispeed electronic let-off system for warp knitting based on closed-loop control strategy. As a demonstration of the capacity and generalizability of this newly proposed methodology, the 01-type four-channel acoustic vibration analyzer is used to test and analyze the time of switching, the let-off amounts, and the change in warp tension during the process of switching let-off amounts, including the explanation and comparison of difference values of let-off quantities. It is shown that the proposed method for the production of warp-knitted fabrics is a useful method for achieving digital manufacture of warp-knitted fabrics.