Measurement of axial motion yarn tension based on transverse vibration frequency

In the process of textile production, the detection of yarn tension is very important to ensure product quality. In order to detect yarn tension efficiently and conveniently, a non-contact detection method based on transverse frequency was established. Firstly, the governing equation of yarn motion was derived by using the Hamilton principle and solved by the Galerkin truncation method. Then, the natural frequencies of yarns with different linear density were calculated according to the yarn characteristic equation. Finally, the fitting formulas of tension, speed, and frequency of yarn axial motion were derived. By measuring the natural frequency of yarn, the yarn tension could be calculated conveniently and quickly. A high-speed camera was used to measure the transverse vibration displacement of yarn and detect the free vibration frequency of yarn. Through experiments, the results of tension sensor and yarn tension detection based on vibration frequency were compared, and the results show that the error was within 5%, which verifies the effectiveness and accuracy of this method.