發(fā)布時間：2018-03-17 11:46

  本文選題：紗線疵點　切入點：光電檢測　出處：《西安工業(yè)大學(xué)》2017年碩士論文　論文類型：學(xué)位論文

【摘要】：在紡織行業(yè)中,紡織品在工業(yè)流水線生產(chǎn)過程中會因原材料、紡織器械、環(huán)境條件等多種因素使紗線表面產(chǎn)生疵點,紗線疵點主要表現(xiàn)為紗線直徑的突變與紗線表面上存在的臟點,這類出現(xiàn)在紗線上的疵點直接影響紗線品質(zhì)。為了更有效管理紗線生產(chǎn)質(zhì)量,本文采用光電法以解決紗線檢測中的關(guān)鍵問題,設(shè)計了一種新型紗線疵點檢測裝置。首先為提高傳感器輸出信號幅值,通過改變光照角度及鏡頭與傳感器焦合位置兩項因素,得到傳感器響應(yīng)信噪比最大時的信號采集方案,并對鏡頭與傳感器進行了合焦結(jié)構(gòu)設(shè)計;其次為滿足FPGA芯片對輸入信號的幅值要求,設(shè)計了信號處理電路,對初始信號進行放大、濾波以提高信號幅值并提升信噪比;通過分析疵點尺寸與其對應(yīng)信號特征,獲得疵點特征函數(shù),取得疵點尺寸與處理后信號的對應(yīng)關(guān)系;為實現(xiàn)硬件識別疵點特征信息,利用FPGA芯片設(shè)計計時邏輯電路與比較邏輯電路,分別對信號進行脈寬及峰值識別;最后利用NiossⅡI軟件開發(fā)平臺,借助構(gòu)建的特征函數(shù)實現(xiàn)脈寬及峰值的標定及特征值存儲及顯示并進行模擬信號測試。實測結(jié)果表明,論文設(shè)計的光電式紗線疵點檢測系統(tǒng)能很好的提取出運動過程中紗線表面特征信號的變化,在實驗室環(huán)境下將系統(tǒng)外界噪聲進行有效的抑制。當(dāng)紗線以30m/min運動,檢測系統(tǒng)能有效檢測出大于50μm的紗線疵點。
[Abstract]:In the textile industry, textiles in the production process of industrial pipeline will cause yarn surface defects due to many factors, such as raw materials, textile instruments, environmental conditions, etc. Yarn defects are mainly manifested in the sudden change of yarn diameter and the existence of dirty spots on the yarn surface. These defects directly affect the yarn quality. In this paper, a new type of yarn defect detection device is designed by using photoelectric method to solve the key problems in yarn detection. Firstly, in order to improve the output signal amplitude of the sensor, two factors, namely, changing the illumination angle and coking position between the lens and the sensor, are adopted. The signal acquisition scheme of the sensor response to the maximum SNR is obtained, and the focusing structure of the lens and the sensor is designed. Secondly, the signal processing circuit is designed to meet the requirement of the input signal of the FPGA chip. The initial signal is amplified and filtered to improve the signal amplitude and signal to noise ratio. By analyzing the defect size and its corresponding signal characteristics, the defect characteristic function is obtained, and the corresponding relationship between the defect size and the processed signal is obtained. In order to realize the defect characteristic information of hardware, the timing logic circuit and the comparison logic circuit are designed by using FPGA chip to identify the pulse width and peak value of the signal respectively. Finally, the software development platform of Nioss 鈪，

本文編號：1624598