On-line discrimination of radial runout state during diamond roller trimming
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摘要: 金刚石滚轮修整砂轮时的性能受其径向圆跳动的影响,而其径向圆跳动状态判别的智能化程度较低。为此,对金刚石滚轮修整状态下的径向圆跳动磨削声发射信号,提出一种基于小波分解和SVM的在线检测方法。将磨削声发射信号通过小波变换并分解,提取小波分解系数的有效值、方差及能谱系数3种特征参数。结果表明:将3种特征参数彼此组合输入到SVM中进行状态识别时的准确率都在96.0%以上;3种特征参数同时输入时的准确率最高,达到了98.3%。该检测方法具有实际应用价值。Abstract: The performance of diamond roller when dressing grinding wheel was affected by its radial runout, but the intelligent degree of judging its radial runout state was low. Therefore, an on-line detection method based on wavelet decomposition and SVM was proposed for the grinding acoustic emission signal of radial runout under the trimming state of diamond roller. The grinding acoustic emission signal was transformed and decomposed by wavelet transform, and the three characteristic parameters of wavelet decomposition coefficients were extracted, which were effective value, variance value and energy spectrum coefficient. The results show that the accuracies of combining the three feature parameters into SVM for state recognition are more than 96.0%. When the three characteristic parameters are input at the same time, the accuracy is the highest, reaching 98.3%. The detection method has practical application value.
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表 1 修整试验参数
Table 1. Trimming test parameters
参数 类型或取值 滚轮直径 D1 / mm 130 滚轮宽度 W1 / mm 16 砂轮直径 D2 / mm 200 砂轮中金刚石粒度代号 120/140 砂轮宽度 W2 / mm 3 砂轮中金刚石浓度 C / % 120 砂轮结合剂 V 砂轮转速 n1 / (r·min−1) 4 000 滚轮转速 n2 / (r·min−1) 70 纵向走刀速度 n3 / (mm·min−1) 2.4 粗修时的进给量 s1 / μm 8 精修时的进给量 s2 / μm 2 精修完成时的进给量 s3 / μm 2 表 2 小波系数有效值
Table 2. Effective values of wavelet coefficients
序号 a5 d5 d4 d3 d2 d1 1 0.177 0.210 0.051 0.026 0.009 0.005 2 0.255 0.201 0.047 0.024 0.008 0.004 3 0.215 0.136 0.037 0.021 0.008 0.004 4 0.023 0.122 0.029 0.016 0.006 0.004 $ \vdots $ $\vdots $ $\vdots $ $\vdots $ $\vdots $ $\vdots $ $\vdots $ 597 0.197 0.195 0.046 0.027 0.009 0.004 598 0.207 0.160 0.041 0.021 0.071 0.004 599 0.238 0.124 0.032 0.018 0.061 0.004 600 0.207 0.160 0.041 0.021 0.071 0.004 表 3 小波系数方差
Table 3. Variances of wavelet coefficients
序号 a5 d5 d4 d3 d2 d1 1 3.1×10−2 4.4×10−2 0.3×10−2 6.8×10−4 8.1×10−5 2.0×10−5 2 3.5×10−2 3.1×10−2 0.1×10−2 5.0×10−4 5.9×10−5 1.8×10−5 3 3.6×10−2 2.4×10−2 0.2×10−2 3.6×10−4 6.2×10−5 2.3×10−5 4 3.5×10−2 1.6×10−2 0.1×10−2 3.9×10−4 4.4×10−5 1.7×10−5 $\vdots $ $\vdots $ $\vdots $ $\vdots $ $\vdots $ $\vdots $ $\vdots $ 597 3.6×10−2 3.6×10−2 2.2×10−2 6.1×10−4 5.6×10−5 1.9×10−5 598 2.8×10−2 1.8×10−2 1.3×10−2 5.5×10−4 6.5×10−5 1.8×10−5 599 3.4×10−2 3.2×10−2 1.9×10−2 5.2×10−4 5.8×10−5 2.0×10−5 600 3.7×10−2 2.3×10−2 1.2×10−2 3.4×10−4 3.8×10−5 1.9×10−5 表 4 小波能谱系数
Table 4. Wavelet energy spectrum coefficients
序号 a5 d5 d4 d3 d2 d1 1 67.23 0.258 0.394 1.749 2.552 27.82 2 81.04 0.312 0.297 1.283 1.804 15.26 3 71.53 0.296 0.266 1.082 2.492 24.33 4 67.07 0.632 0.556 2.219 3.257 26.26 $\vdots $ $\vdots $ $\vdots $ $\vdots $ $\vdots $ $\vdots $ $\vdots $ 597 52.97 0.748 1.031 3.956 4.895 36.61 598 61.74 0.256 0.419 1.875 3.101 32.61 599 53.27 0.239 0.242 0.983 1.323 43.94 600 53.94 0.329 0.357 1.620 2.447 41.31 表 5 修整状态分类测试的准确率
Table 5. Accuracy of trimming state classification test
输入的AE信号
特征参数输入特征个数m SVM的准确率
Ac / %$ {X}_{rms}^{m} $和$ {V}_{var}^{m} $ 12 96.8 $ {X}_{rms}^{m} $和$ {\eta }^{k} $ 12 96.5 $ {V}_{var}^{m} $和$ {\eta }^{k} $ 12 97.2 $ {X}_{rms}^{m} $、$ {V}_{var}^{m} $和$ {\eta }^{k} $ 18 98.3 -
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