Noise Source Identification Method for a Carpet Tufting Machine Based on CEEMDAN-AIC

In recent years, the noise reduction research of the carpet tufting machine has been developing slowly. The research gaps of the existing work mainly focus on the noise source identification for the carpet tufting machine. MEEMD (EEMD) has been proposed to apply to source recognition on textile machinery. Due to the uniqueness of the MEEMD/EEMD, it is difficult to set suitable white noise control parameters. MEEMD (EEMD) has only been tested via simulation; however, it has not been mathematically proven or evaluated. This leads to inevitable flaws in the research conclusions, and even some conclusions are wrong. The contribution of this paper is twofold. First, in order to recognize the noise source of a carpet tufting machine, a method based on complete ensemble empirical mode decomposition (CEEMDAN) and Akaike information criterion (AIC) is proposed. The CEEMDAN-AIC method is applied to measure the noise signal of a carpet tufting machine and analyzed every single effective component selected. Noise source identification is realized by combining the vibration signal characteristics of the main parts of the carpet tufting machine. CEEMDAN is used to decompose the measured noise signal of the carpet tufting machine into a finite number of intrinsic mode functions (IMFs). Then, singular value decomposition (SVD) is performed on the covariance matrix of the IMF matrix to obtain the eigenvalue. Next, the number of effective IMFs is estimated based on the AIC criterion, and the effective IMFs are selected by combining the energy characteristic index and the Pearson correlation coefficient method. Furthermore, reconstruction and comparison of the decomposed signals of MEEMD and CEEMDAN proved that CEEMDAN is effective and accurate in source recognition. The results show that the noise signal of the carpet tufting machine is a mixture of multiple noise source signals. The main noise sources of the carpet tufting machine include shock caused by the impact of the tufted needle and looped hook and vibration of the hook-driven shaft and pressure plate. It provides theoretical support for the noise reduction of the carpet tufting machine.

The Dynamic Balance Research of Shaft System in Carpet Tufting Machine Based on Matlab

Simulation studies were carried out on the shaft of carpet tufting machine to establish multi-parameter dynamic balancing equations based on Matlab. Through the analysis and comparison of reaction forces between link and spindle before and after dynamic balancing, the optimal parameter solution was acquired under the ideal state. According to the actual situation in the project, the optimum value was obtained by modifying some parameters, which not only made mechanism achieve a better balancing, but also enhanced the transmission of motion performance and improved the operating environment of spindle system.

Design of CAN-Bus Based Yarn Feeding Control System for Carpet Tufting Machine

This paper proposed a CAN-bus and stepper motor based yarn feeding control system for tufting carpet machine. Base on requirement of yarn feeding devise control system architecture. Control system adopts the industrial computer as the master platform and user interface, the lower computer consists of yarn feed step motor controller, speed synchrony controller and yarn guiding controller. Design the communication protocol and the control logic. Through establishing control system prototype system to verify the system function, test results show that the design scheme is feasible

Yarn Feeding Change Analysis for Needle Bar Transverse Shifting of Carpet Tufting Machine

The needle bar transverse shifting would likely form the stop mark on the tufted carpet. Focus on this problem, through analysis the change in yarn feeding path and loop pile forming, construct the mathematical model of length change of yarn feeding in path and usage of loop pile forming while needle bar shifting. Base on the mathematical model analysis key influence for yarn feeding path change. The analyze result is useful for yarn feed compensation solution

Yarn Feeding Compensation Algorithm and Implementation for Needbar Transverse Shifting of Carpet Tufting Machine

The needle bar transverse shifting will likely form the stop mark liked gap on the tufted carpet. This paper proposed the yarn feeding compensation scheme and illustrate implement method in detail. Through analysis the change in yarn feeding path and loop pile forming of carpet tufting machine, construct the mathematical model of length change of yarn feeding in path and usage of loop pile forming while needle bar shifting. According to the mathematical model for yarn feeding compensation, calculate the additional yarn feeding requirement. Base on jacquard control principle, dynamic control the yarn feed actuator to drive the yarn feed roller to delivery additional length yarn, and produce loop pile with predefined pile height, Test result show the compensation is feasible.