Design And Implementation Of On-line Yarn Defects Detecting System

It is the increasement of people’s requirement to yarn quality and the spread of rotor spinningtechnology that together promote the development of online yarn defect detecting and controlingsystem. Currently fieldbus-based distributed architecture has become the development direction ofyarn quality detection system. In this paper, we designed a distributed control system for onlinedetection of yarn defects based on the environment of a rotor spinning machine workshop.Firstly, this paper analyzes the characteristics of several common industrial fieldbus, and putforward the overall system architecture and communication programs considered combine with theactual situation of small and medium sized textile enterprises. Then we compare the advantages anddisadvantages between photoelectric sensors and Capacitive sensors, and established a photoelectricsensor of the present yarn defect detection probe that is used. According to the environment andtesting requirements, we designed the probe’s hardware and software to achieve the yarn defectdetection. Then we designed the debugging PC software using C#and the IAP applicationprogramming software. Respectively, we tested the detecting effect of the detection probe in alaboratory environment and then spinning machines work-site. Finally, we summarized the workdone during the design process of this paper and gived some outlook, then pointed out t some of thedeficiencies in design and showed the follow-up for further research.The online yarn defect detecting and controling system we designed has the followingfeatures:(1) In order to meet the needs of small and medium textile enterprises to group control2000yarn defect detection probes, we used a system architecture within Ethernet-CAN bus-RS485bus,which not only realized of remote access and monitoring of the spinning workshop productionsituation, but also saved the hardware cost of each test probe.(2) Yarn defect detection probe usedphotoelectric detection principle to detect the effect so that it is not influenced by humidity.(3) theinfrared emission of yarn line defect detection probe used programmable constant current sourcedriver, yarn thickness signal that infrared receiver outputted is conditioned from a function withzero gain control instrumentation amplifier, combined with the software within automatic Zeromodule and yarn count adaptive module, it can overcome the changes in environmental temperatureand humidity,the fly shop and fouling, the impact of photoelectric sensors to detect the effect ofindividual differences, and automatically adapts to the number of yarns of different measurementrequirements.(4) Using the communication between sender IAP upgrade program and the receiverUser-Bootloader program, yarn defect detection probe can achieve in applications programmable system, by which user can upgrade the APP program to be updated via RS485bus sent to thedetection probe. Thus eliminating the need for repeated mating probe housing demolitioninstallation, cable connection download download programs, etc., to facilitate debugging andsystem software upgrades, reducing the subsequent system maintenance costs.This paper presents a distributed online yarn defect detection system architecture, and then wecompleted the yarn defect detection probe based on photoelectric detection principle, whichachieved the real-time detection of the neps, the short and thick yarn fault, the long and slubs yarnfault, the long and thin yarn fault, which is produced during rotor spinning machine workingd. Afterapplication of the laboratory and the field of textile machinery airflow tests, we find that the probeto achieve the desired requirements, which can quickly identify the set of yarn defects and uploaddata, the system basically meet the air spinning machine shop applications.